The trick yourself into cherry picking thread is too long. I’m opening this one!
The previous thread is here.
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429 thoughts on “New Cherry Picking Thread!”
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Kuhnkat
What’ll they think of next? That CO2 freezes in Antarctica?
Ryan O (Comment#22344) October 22nd, 2009 at 6:06 pm
So you believe that the methods used to reconstruct the past 2 millenia have the discrimination to show that the 1850-2010 temperature change is unprecedented?
No, I doubt that.
.
And given that this temperature change is a 150-year episode (kinda-sorta), do you really think that a sampling period of only about 13.5 times that period is sufficient to exclude the possibility that it is within the range of natural variability?
No, I don’t.
.
If so, then that is where we disagree sharply.
Well, it seems we agree more than you realised! Ryan, I carefully wrote “To the extent that the reconstructions are reliable…”, I didn’t say that I thought they were. However, whatever doubts I have about the quality of these reconstructions, they are at least equalled by my doubts about any case I’ve ever seen put for a global MWP equivalent to today’s temperatures. My view is that we don’t have good enough knowledge of this either way.
Geoff Larsen (Comment#22349) October 22nd, 2009 at 7:22 pm
Geoff,
I think you have misunderstood the point I was making. I am not asserting that the models are good models. I happen to think that they are quite likely to have aerosols and ocean response rate significantly ‘wrong’. I was simply responding to Carrick’s discussion of what the models ‘tell us’, clarifying what they have told us (such as they are).
bugs (Comment#22382)
October 23rd, 2009 at 12:44 am
“Broken my irony meter again.”
What breaks *my* irony meter is the forcefulness of assertions by people who have not the mental strength to read or write or do basic arithmetic. My advice is to spend more time in school, less time in church.
Bender Baby…
Come on… That’s not very nice behaviour.
Besides, I’m an atheist.
Hey you never pointed to the part of the Broecker paper you were so excited about.
You did not answer the question. So you have not learned. Why was the article written? Because the MBH recon was not credible. Academics do not use words like “voodoo”. As I said you must read between the lines. If you can’t find the lines, this points to your lack of reading comprehension. No surprise.
.
Your chacterization of Broecker, based on his wiki entry, as a hockey-stick supporter is pure deceit. I hate precisely what you love – quote-mining & cult of personality – but here is one for you:
“The climate system has jumped from one mode of operation to another in the past. We are trying to understand how the earth’s climate system is engineered, so we can understand what it takes to trigger mode switches. Until we do, we cannot make good predictions about future climate change.”
This is a better characterization of his POV than your fabricated story about his support of hockey sticks.
Your arguments are so flimsy I can only imagine you are trying to do the action movement some harm.
Your deceitfulness is disgusting.
Nathan (Comment#22392)
October 23rd, 2009 at 4:14 am
“I’m an atheist.”
You’re a propagandizing proselytzing warrior.
“Look at Wallace S. Broecker’s wiki entry, it’s hilarious that he’s Bender’s darling defeater of hockey sticks”
To repeat, Broecker’s approach to the incredibility of Mann’s hockey stick was different than McIntyre’s. Broecker (2001) suggested that this simply didn’t make sense to him, and explained why, based on the far reach of the THC. McIntyre, in contrast, SHOWED why by auditing the paper to its ugly death. But look at the Team response in both cases. Published. Denial and disengagement. Unresponsive responses.
You will not learn unless you answer my questions.
But as you said: you’re not here to learn. The facts are irrelevant.
Bender
Don’t be ridiculous, calm down.
WHere does he say he hates the Hockey stick? You gave me one article from 2001, I quoted EXACTLY what he wrote. Do you have any other evidence? He says at the end of the 2001 paper that he see further work is required, was any done?
I didn’t fabricate anything, I posted links and quoted exactly what he said. Yo haven’t done anything at all.
I presented an article he wrote in 1987 that showed him demanding action on climate change. All through the Wikipedia entry it talks about how he thinks we need to act on climate change.
Where else (other than the 2001 article) does he mention MBH?
Simon Evans, may I compliment you on your logic and writing? What a breath of fresh air.
Broecker (2001) made a statement. Why should the same statement ever be published twice? The statement – if you look at the figure in his graph – is that the MWP was missing from the MBH hockey stick recon. This made no sense to him because it would require removing the effect of the THC that, in his opinion, accounts for both the MWP and LIA – as part of a 1500-year cycle.
The irony, lost on you, is that it is the guy who coined the phrase “global warming” who first stood up to the sham junk science of MBH98. I thank you for bringing that irony to my attention.
Please. Stop doing the action movement so much harm by spilling junkbrainstuff everywhere. No argument is better than a bad argument.
“I didn’t fabricate anything”
.
fabrication #1: “you just want to avoid mitigation.”
fabrication #2: “Quite clearly he is very upset about the Hockey Stick ”
fabrication #3: “he’s Bender’s darling defeater of hockey sticks”
fabrication #4:
“Are you sure he’s a “no action†kind of guy?”
Thanks Lucia
Bender,
He does discuss MBH in the opening paragraph. I quoted his first final paragraphs of his conclusions before, which stated that their was too much uncertainty to be definitive (about the MWP) and that more work needed to be done. I then looked up what he had done since then on Google Scholar. He’s done heaps. I couldn’t, however find anything about ‘further work’ on this issue. I then looked at his Wiki page, and it talks about how active he has been in trying to mitigate against the effects of CO2.
So even if he still thinks the Hockey Stick is wrong, he quite clearly thinks we should be reducing of CO2 output. This, actually, was my initial point. It doesn’t really matter if the MWP existed or not, we still need to take action (which Wallace S Broecker was advocating in 1987).
Ummmm If I “Fabricated” those statements – then you fabricated that he said voodoo.
Sadly Nathan starts off this continuation by not coming within cooee of what your original thread was about. There was some very interesting (from various viewpoints) discussion on your “reconstruction” but after Nathan materialised I have given myself RSI scrolling past his unicorn efforts.
What a shame. It was a very good post.
GrantB–
I’m going to migrate the past “N” posts to the top of this thread around 8 am Chicago time. (I wanted to eat breakfast first.)
You love quote mining. I do not. Brocker (2001) pointed to MBH voodoo. Of course he did not use those words. I pointed that out myself. I never claimed to be quoting him. In contrast to you.
McIntyre showed the source of the voodoo. Wegman confirmed it. Yet the hockey stick voodoo continues. Why? Why are they addicted to California pines and Yamal larch, like crack? Why? Why the cherry picking?
You love quote-mining. What did Deming say? Was he lying? What’s your evidence?
What was Broecker (2001) getting at? Why did the man who coined the term “global warming” take a stand against voodoo mathematics?
Your lack of curiosity is amazing.
GrantB: –
I am trying to stay on-topic. Hopefully you can see the effort and can appreciate the challenge I am facing.
It is utterly disingenuous for a warmer to say that the existence of the MWP does not matter because:
1) It’s existence along with the LIA are evidence of natural fluctuations that (a) possibly exceed the current warming and (b) are not explained by the models.
2) The MWP was generally presumed to exist by scientists until the “we have to get rid of the MWP” idea arose in support of the beleaguered Hockey Stick and made the MWP an ideological battle line. Minimizing or eliminating the MWP is clearly deemed ideologically necessary by the leading lights of AGW.
I particularly enjoyed the circular argument deployed by Nathan about the “imaginary” causation of the MWP: The proof of AGW models is that they account for past and present climate records; if any such records do not conform to the model, they must be wrong because the models don’t explain them, thus the models are always right. And best of all, deniers have the burden of coming up with ways to prove the models are still right even if past records do disagree, otherwise they are guilty of espousing “imaginary” effects.
The precautionary principle also suggests that the MWP is important. If there are significant climate swings we don’t control and can’t explain, then our current modeling is less likely to be right. Given that it is absolutely certain that drastic curtailment of fossil fuel use without the simultaneous availability of cost-effective substitute technology would cause economic harm of Hansenesque proportions, the levels of probability regarding AGW worst-case modeling matter a lot. Offering breezy assurances that the Hockey Stick does not matter after all does not cut it.
“even if he still thinks the Hockey Stick is wrong, he quite clearly thinks we should be reducing of CO2 output. This, actually, was my initial point”
Actually, it is your *only* point, and it is why the thread is being derailed – because it has nothing to do with the topic. Or the blog, for that matter. Good bye! Forever!
Nathan’s subsequent contribution was a question: why does the MWP matter? Who cares what the magnitude was? So what if someone cherry picks to reduce the MWP? This was explained by several commenters. Then he asked what the evidence was for a concerted effort to reduce the MWP. I pointed out the Deming quote. Simon asked if there was proof of an email to Deming. I conceded there was no proof. But rather than ask for evidence of conspiracy – which is never easy to prove – I pursued a more evidence-based line of enquiry: “why did Broecker take it upon himself to write the 2001 paper?” “Did he think something must have been awry with the MBH98 calculations?” “What was his main argument?” And “what was the Team reply?”
Nathan has dodged every single one of these questions. Brocker was basically challenging MBH to show the goods. They refused. McIntyre did a Heimlich on them and made them cough it up, bit by ugly bit. And the voodoo methods are still coming up. Whatever the Team swallowed (in 1995?), there’s still some of it left down there.
crack is a tough habit to kick, no?
Ask yourself this question:
“If someone *did* want to erase the MWP, how would they do it?”
Now: forget motives. Just look at methods. Does the shoe fit?
Georrge Tobin says:
“The precautionary principle also suggests that the MWP is important. If there are significant climate swings we don’t control and can’t explain, then our current modeling is less likely to be right.”
Seems to me that is what the Broecker quote from the wiki page was suggesting. Let’s get the science right so we can take the right course of action. Let’s not use voodoo math just to advance a particular political cause.
[Nathan, these are not quotes.]
fabrication #5: “Where does he say he hates the Hockey stick?”
This shoe does not fit. As far as I know, McIntyre has never argued that MBH98/99 depressed the medieval warm period, but rather that the blade of the hockey stick was a statistical artifact and that, therefore, tree rings are not suitable temperature proxies.
So, it would be a very bizarre way of intentionally depressing the MWP.
By the way, can you please point to the reconstructions prior to MBH that show a pronounced MWP?
Morning Bender!
Isn’t Nathan a joy. He’s like Tom P without the bad code. It’s funny Sometimes I look back to 2007 when I started to hang out at RC, I didn’t know shit so I mined quotes. That way I could turn the debate to a playing field (exegesis) where refutation was well nigh impossible. All you needed was google and professional training in sophistry. And with hank roberts around most of the google searches were already done. Every post becomes a mini version of a freshman paper.
Anyways, It is a joy to see roman at work.
WRT MWP. I’m a hedgehog. I’m stuck on the modern day instrument period. You know basic stuff like getting NOAA to release its source data and code, hadcru etc. I don’t object to arguments about MWP but they are, to me, arguments about data and facts I haven’t even stipulated to. Were I to stipulate to a figure for the modern period I’d agree with Mac prior to 1800 you’ve got floor to ceiling CIs.
So basically you’ve got a worldwide grid of temperature stations that supposedly have measured what? maybe a 1C increase in the last 120 years or so ( giver take) and you’re telling me that using a sparse network of tree sites you are going to estimate the temperature of the mideval period using tree rings ( err 12 or 10 or 5) tree rings which only capture a seasonal temperature signal, tree rings that are corelated with instrumented temps at marginal levels.. You are going to do this and have a error bound that allows you to say the MWP was lower or higher than the present day? Son, I’m gunna need to see all your work, every last step. every piece of data you collected, every piece of data you trashed, every sneaky little data mining code you wrote ( you know those programs bender, wink wink)
Ok.. I’m headed to the pool.
Boris, the “pre-Mann” reconstructions were reviewed and consolidated by the IPCC into a pretty widespread figure in the 1990s with a pronounced MWP and LIA. I haven’t backtracked the individual reconstructions lately, but googling turned up the IPCC’s own plot at John Daly’s site. (a now deceased skeptic). (I’m not endorsing that page, just pointing out the digitized Figure 1.)
http://www.john-daly.com/hockey/hockey.htm
The scientific discussion pre-Mann revolved around “How -much- of the warming is -A-GW?” It is a quite tricky question to answer… unless the normal state of the whole climate is essentially flat – and now it is not.
Boris,
I won’t speak for steve with absolute authority but I’m fairly confident that his position is that prior to 1800 the CIs are floor to ceiling. I would argue that his position ( and probably benders, and romans, and UCs and jean S, position ) is that the current data ( metadata as well) and accepted methods of reconstruction lead to a situation where prior to 1800 the CIs are unbounded.
The shaft is indeterminate.
That is why, precisely why, St. Mac refuses to do his own recon. Read his interview in the times. Maybe I’m mispresenting him. bender, what say you?
But enough of the MWP.
I take the Team stick that McIntyre broke and I give the shaft to Nathan and the blade to Boris. Run along. Go play in traffic, boys.
“prior to 1800 the CIs are unbounded”
I think they are bounded, but so wide that no MWP vs CWP difference can be declared. So, hey, go smoke your tobacco. Enjoy. Heck, Ben Hale’s grandpa said it’s not only safe, it has remarkable health benefits. Precaution shcmaution.
Simon . . . I am pleasantly surprised to see that we agree. 🙂
.
Mosh . . . well said. Both posts.
Alan S. Blue,
That figure from the AR1 is a single regional temperature record based on UK proxies. I wouldn’t necessarily tout it as proof of anything :-p
Just say this with Yosemite Sam’s voice and gestures: “New Cherry Picking Thread!”
Not “proof” no. But that was the sort of reconstruction that was available and accepted pre-Mann. Whether it was justified or not in hindsight, that was what there was. The southern hemisphere data sucked. When it differed from the the north it was marginalized or attributed to local conditions etc.
What breaks *my* irony meter is the forcefulness of assertions by people who have not the mental strength to read or write or do basic arithmetic. My advice is to spend more time in school, less time in church.
I know I’m not scientist. Do you?
Yes, bugs, bender knows you’re not a scientist. We all know.
At least we pray to our deities…
bender (Comment#22421) October 23rd, 2009 at 4:05 pm
yes I was less than precise.
Bugs when I predict that you will say something stupid and you do, I am being a scientist. When you repeat the same behavior and expect different results you are being a mental patient. I know thats funny to everyone else, but seriously if you want to change our beliefs and actions ( like the words we write) then you should try some different behaviors. or not.
I know thats funny to everyone else, but seriously if you want to change our beliefs and actions ( like the words we write) then you should try some different behaviors. or not.
Nothing I can say will change your minds. It’s like arguing with a creationist. There is always something that you demand has to be explained, and you think that invalidates the whole case for AGW. You will always be able to find something that you will demand has to be explained. Just like the creationsists. Meanwhile, the big picture is pretty clear, it’s AGW, it’s going to be a problem.
I know thats funny to everyone else, but seriously if you want to change our beliefs and actions ( like the words we write) then you should try some different behaviors. or not.
I met a climate researcher once. I asked him what he thought of people like you. For him and his colleagues, you are completely irrelevant, and not worth a seconds thought. You are not part of the scientific process, you do not understand what they do, you will, however, believe various nonsense if it confirms you prejudices. The research progresses, they do their job.
Bugs: “you think that invalidates the whole case for AGW”.
Who are you talking about? It can’t be our host, it can’t be Mosher or Bender. I think you need to be way more explicit. Who is saying that the whole case of AGW is invalidated by what? What are those “demands” that you find so unreasonable? Is it the demand for certain scientists to free the code and show the data?
Bugs: “you think that invalidates the whole case for AGW”.
Who are you talking about? It can’t be our host, it can’t be Mosher or Bender. I think you need to be way more explicit. Who is saying that the whole case of AGW is invalidated by what? What are those “demands” that you find so unreasonable? Is it the demand for certain scientists to free the code and show the data?
bugs
Huh? You were responding to moscher, who believes the theory of AGW. You seem to have some strong filters set up preventing you from observing facts or process what they say. This may be why you are unable to communicate to people and develop weird theories about what may, or may not, ‘convert’ them to believing whatever the heck it is you specifically believe.
I’ve met loads of climate researchers. My husband worked on ARM/ SHEBA (i.e. he did funded climate research.) Two years ago, he switched to homeland security. I’m not sure what you talked to the climate researchers about, but if you only met one, it’s unlikely you know what most or all climate researchers think about “people like steven”.
Given the fact that you can’t even keep track of who does or does not believe in AGW, it’s unlikely you even know what 1 researcher thinks about “people like steven”, because at best, you learned what he thinks about some fictional person you described to that one researcher.
So now we are creationists, eh?
Bugs is rather irrational, me thinks…
Alan (22418),
The graph in Figure 7c of the IPCC First Assessment Report was derived from Lamb’s representation of the Central England temperature estimates (the instrumental record for the area runs from 1659), according to Steve McIntyre’s exposition here:
http://www.climateaudit.org/?p=3072
This is, of course, a representation of one area and is not any type of reconstruction of global or hemispheric temperature. As will be noted from Steve’s post, even that graph of Central England, when brought up to date, suggests current temperatures above Lamb’s estimate for the MWP (though not by much).
For interest, the HadCET graph of the instrumental record for the region is here:
http://hadobs.metoffice.com/hadcet/graphs/HadCET_graph_ylybars_uptodate.gif
Lamb took the view, in 1965, that an MWP was suggested by evidence from various parts of the world over two to four centuries, although he did not assert that such evidence was synchronous, and he certainly did not present the CET graph as a representation of global temperature.
To be clear, I think there is not good evidence of European temperatures (thus including Central England, of course) being higher now than over the past millenium. I also think there is not good evidence of an MWP being globally synchronous, nor of average global temperatures at such a time even if it were.
One of the things that confounds the discussion of AGW is that the meaning of the term is not used the same by all parities nor used the same way in different discussions.
Consider “Affirmative Action”. One side feels that disagreeing with setting aside slots in a freshman class at University is being against “Affirmative Action” while the side disagreeing says that they’re for AA but they’re just against quotas.
With AGW, lukewarmers or those who don’t believe in catastrophic AGW are considered deniers by those who do. For example our host here and at CA don’t deny GW but are still called deniers by those at RA.
Maybe we need to use the term CAGW instead of AGW.
bugs:
I’m like the others, who do you think the “whole case for AGW” is invalidated?
Many of us, myself included, accept the reality of AGW.
We just aren’t cult followers of the secular religion of AGW, unlike some of the trollish commentators on this blog.
The problem with AGW vs. CAGW is that they are the same thing.
It’s like describing an automobile as a “slow car” or a “fast car”. The description depends on what the car is doing relative to something else.
‘Catastrophic’ means what? Catastrophic for who, where and when?
This is why the Lukewarmer Position is as fallacious as the Standard Alarmist one. It’s tries to appease reason (which yells “lets do the science right!”) and be a faithful AGW disciple (which yells, “we still believe!”) at the same time.
Andrew
BarryW,
Is CAGW “catastrophic” AGW?
I agree there are hoards of people “out there” who seem to think that all people fall into two camps. These might be called “stone cold denialists” and “hellffire and brimstone warmers”.
The “stoners” appear to believe that everything associated with the idea of AGW not only false, but the theories and ideas were created by some cabal of climatati for nefarious reasons. They don’t believe radiative physics applies to the atmosphere, they think models are absolutely, totally, completely tuned, as in “input = anything” output =”catastrophe”. They believe the climatati’s nefarious reasons may be desire for funding, religious fervor motivated by a believe in the goddess GAIA, love of socialism, desire to get rich selling carbon credits or what have you.
The “hell-firers” appear to believe that any and every possible prediction associated with AGW must be true. They appear to seriously believe the northpole will be ice free in winter by next year, NY city will be partially underwater within 5 year (possibly looking like the cover of Joe Romm’s book), every fire anywhere in the world was caused by AGW, and that all heat waves are caused by AGW (while cool spells are “just weather”.) The appear to believe climate models are perfect (even if they predict different things.) They also seem to believe that saying a model is “useful” in some unspecified sense means that people must conclude the are “perfect”– and that people may not doubt that the absolute worst outlier predictions are almost certain to occur.
The hell-fire-ers also seem to believe that anyone who believes AGW is true, but that the multi-model mean predictions of computer programs might happen to be high due to our imperfect understanding of models must really be a stone-cold denialists. In fact, it’s perfectly possible to believe models might be… get this… not particularly accurate and biased high without denying AGW!!
Andrew
No. They aren’t the same thing. But there are problems with the term. One problem is figuring out the dividing line. The other is figuring out the metric for the dividing line. Is the belief in CAGW based on how hot you think the world is going to get? (That is, do you believe GMST will rise 1C vs 6 C? next century?) Or is the believe in CAGW based on the level of action you think is required? (Should we shut down all coal fired plants today? Kill all our pets? Or can we slowly taper off? Can we accept 1C temperature rise to maintain the economy while we develop and deploy better solar, wind and nuclear power generation capabilities?)
Or what?
Lucia,
The answers to your questions are “Nobody Knows” how hot the planet is going to get or what we should do about things we only imagine could be in our climate future.
The scientists that are supposed to be helping us start to answer these questions are doing everything but helping. What we have been handed is a non-scientific “consensus” of scientists who say you should believe in this pile of dung we made (climate science). That is not very helpful.
Andrew
Andrew,
Lucia made my point for me (yes the “C” was for Catastrophic). The range of opinions about what AGW means is a continuum. One of the things I can’t abide is the hell-fire position that bad science is ok as long as it supports their position. How can I trust anything they are saying when they are using falsehoods to support their position. It makes climate science akin to creation science.
There are even those of us who believe there is some CO2 based warming but our response is “So what?”. My take is warm is better than cold. Both can cause disruptions but humanity can survive a warmer earth better than a colder one.
BarryW
“How can I trust anything they are saying when they are using falsehoods to support their position.”
I agree completely and unreservedly with the validity of your question. 😉
Andrew
lucia (Comment#22445)-“all heat waves are caused by AGW (while cool spells are “just weatherâ€.”
I’ve heard worse-some people seem to believe that cold weather is caused by AGW.
To change the subject slightly to the original subject of the post:
If you have n sets of data, where each data set represents a rtime series in period T, and if the time series has a zero mean over the period, and if the variation of the time series is a unique a) an explicit periodic function or b) a red noise function or c) an autocorrelated function , then if you curve fit to a portion of the series then immediately you violate the zero mean property of the data set, and you will get spurious correlation for some of the data sets provided n is sufficiently large. A white noise test won’t do this.
Now with regards to radiative physics and CO2, yes Co2 absorption and emission of IR is well characterised but the atmosphere does not rely on radiative processes alone. From the start all the models assume a radiative-convective coupled process. This means that you need to measure the coupling between water vapour, Co2 and ozone with different levels of humidity and pressure to understand the atmospheric processes better. Jim Hansen estimated the forcing effect from a model but no-one yet has measured forcing in a lab. Hence it is reasonable to assume that the forcing figure may be out by a up to a factor of 5. To all those people who think that, because the radiative physics is well known, that this means we can say more CO2 causes more heating of the Earth’s surface I say they don’t have experience of coupling phenomena. It is highly possible, and this needs to be tested, that the radiative process for CO2 is limited to suit the convective nature of the atmosphere. Or that water vapour processes are prevented from going seriously chaotic by CO2. Now it also may be that this little to no coupling and the radiative process of CO2 can be assumed to be independent of water vapour processes.
But you have to test this. You can’t just state it as an assumption and fiddle your model to suit.
” take the Team stick that McIntyre broke and I give the shaft to Nathan and the blade to Boris. Run along. Go play in traffic, boys.”
No attempt to answer, huh? That’s because as Simon points out, there was no global MWP to “get rid of.”
I have no problem with people who think the CIs are too wide to decide–but the argument that people were inventing methods to remove some agreement on the MWP when no agreement existed makes no logical sense.
Trying to make MBH98 into a conspiracy theory doesn’t do your side any good, FYI.
“there was no global MWP to “get rid of.â€
How do you know?
Andrew
Andrew_KY–
If the data do not support small confidence intervals, then we can’t know if the MWP existed or not. So, in that sense, there is no known MWP to “get rid off”.
Or course, as a matter of historical fact, either the MWP happened or it did not. No one really can “get rid of it” or “create it out of thin air”. They can only “get rid of” it in the sense of creating uncertainty about it’s existence.
On the other hand, if the data are sufficiently good to have small confidence intervals,we have a shot at confirming or refuting the theory– whose possible positive evidence mostly consist of scattered historical records or temperature and weather reported by people living during a particular time period.
Boris (Comment#22452) October 24th, 2009 at 1:07 pm
Then you an I have no substantive issue between us. I remain unconvinced that the CIs are narrow enough to tell us anything with the kind of confidence we need. but I’m open to be convinced.
Motive hunting about the construction of recons that show a MWP lower than today is fun, but unscientific fun. Like you I find the conspiracy theorists ( I think I was one once) a bit unhinged. However, the constant re use of certain proxies lets say yamal, any stripbark, and manns PC1 also points to some kind of weird behavior and is not good for your side.
Lets put it this way if all reconstructions are sensitive to the inclusion or exclusion of a few series that should give any objective person pause.
In anycase I think the MWP is so far down the chain of evidence that it baffles me why people even argue about it… wait that IS why they argue about it.
Nicely done lucia.
One of the victims in the black and white view of things is the death of dialogue. I think there are reasonable people who understand that there are many gray areas here, but we are not allowed to discuss these gray areas. In part the AGW crowd has got the notion that they need to fight against the notion of UNCERTAINTY. why? because uncertainty implies a wait and see attitude, a do more study attitude, a modest action attitude.
For example they point to the way the tobacco industry fought legislation with doubt. So doubt is the enemy. That’s a tough position for any scientist to take. This attack on uncertainty culminates in the precautionary principle which As I first pointed out is nothing MORE than Pascals wager. People get unhinged when I point this out, but for me it is nothing more than objectively looking at the structure of argumentation. Maybe someday I will point to william james essay on the “will to believe” and how it maps onto the debate over climate science, especially in the area of confirmation bias.
Who was the first ‘scientist’ to suggest that the MWP did not exist ?
Steven (mosher),
I agree with most of what you’ve said in your last couple of posts, but not, actually, with the view that “uncertainty implies a wait and see attitude”. We are uncertain ‘both ways’, I think? In most circumstances in life where we have uncertainty to face I think we are prepared to consider insurance costs, no? I am not very uncertain about the responses to warming over the last century, nor particularly uncertain as to whether further warming would be stressful or not. I am disinclined to think that continuing regardless to pump GHGs into the atmosphere is a very smart idea, even though we may not be certain in agreement as to the projected impact of doing that. What do you think?
Simon–
I think there is enough evidence for AGW to make a strong case for some action. I think we should develop and deploy less carbon intense power generation methods, including solar, wind, and nuclear (and anything else that makes sense.)
I’m also for throwing some money at developing methods to extract and store CO2 from flue gases to keep it out of the atmosphere etc. All these need to be on the table and discussed. The more promising need to be encouraged in some way.
I’m not for killing all our pets, or shutting down all coal fired plants tomorrow with no plan to replace with nuclear etc.
Why does everyone act like the MWP was during pre-historic times? It wasn’t. They had written language then and recorded history. Maybe some historians should also get involved in the debate. There may be many obscure documents from the MWP that could shed additional light on the issue.
John Phillips–
The difficulty is that we don’t have obscure documents from all parts of the world. So many American writings that might have told us something destroyed by Conquistadors. Some parts of the world didn’t have any sort of writing at all.
In anycase, there were no thermometers, which affects the level of certainty.
Lucia,
Thanks for a summation of the possibilities.
Nobody Knows if there was a MWP or if there wasn’t. There could have been. Maybe. 😉
Andrew
Tony Hansen (Comment#22458) Nobody suggested there wasn’t one per se. The evidence from the North Atlantic region, especially Europe, has long been reasonably clear, enough so that MBH 1999 asserted that evidence indicated that it didn’t dominate the entire hemisphere, but did “exist”.
Simon Evans (Comment#22459)-“n most circumstances in life where we have uncertainty to face I think we are prepared to consider insurance costs, no? I am not very uncertain about the responses to warming over the last century, nor particularly uncertain as to whether further warming would be stressful or not. I am disinclined to think that continuing regardless to pump GHGs into the atmosphere is a very smart idea, even though we may not be certain in agreement as to the projected impact of doing that.”
When a person decides to by insurance, they consider not just their risks, but the cost of the policy, and how good an effect it has on reducing their risk. In this respect, current policy propositions constitute terrible “insurance”, since they represent minimal coverage at high premiums. This doesn’t mean there aren’t things worth doing, but most of those are in the realm of reducing our vulnerability-we are far to vulnerable to the existing climate in many respects.
And whether emitting CO2 is a “good idea” or not in your eyes doesn’t change the fact that, for the time being, our use of fossil fuels is the only way to maintain our standard of living, and the only way that those in the developing world will be able to improve theirs.
“I think there is enough evidence for AGW to make a strong case for some action.”
Excuse me Lucia, but what specific evidence are you referring to?
Can you provide a list or something?
Andrew
I actually agree with Boris. I have no idea if there was a suggestion by Jonathon Overpeck, captured by David Deming, that someone should “eliminate the MWP”. But Mosher is right too. How do you account for the Team addiction to flawed proxies and proven bad methods, including cherry-picking? Check out the latest crap they’re pushing.
steven mosher
.
“In anycase I think the MWP is so far down the chain of evidence that it baffles me why people even argue about it… wait that IS why they argue about it.”
.
The MWP is far down the chain of evidence for AGW but it is extremely important for CAGW because CAGW requires that one believe the climate models accurately represent the climate system. If the MWP was real and hot then that claim would be much harder to make.
Bender
You are a goose.
You keep saying I quote mined, well at least I quoted what the author said rather than making up an interpretation of what the author said.
Your whole case the Broecker thinks the Hockey Stick is broken revolves around his 2001 paper. In that he clearly talks about how there is a need to do further work to demonstrate the MWP. There was no further work (by him) on it. He clearly articluates a case for action on AGW – as late as 2008 (and as early as I can find as 1987). What else have you got? It would seem he’s still an alarmist.
My whole argument is there is a case for action without the Hockey Stick. I am not alone on this blog in that belief (See Lucia above). Steven Msoher points it out best here:
“In anycase I think the MWP is so far down the chain of evidence that it baffles me why people even argue about it…”
I brought this up at CA for this exact reason. I was baffled why CA has continued for 10 (?) years to focus on proxy reconstructions, when they are really pretty low hanging fruit in the whole let’s act on climate change tree.
We may all differ on the magnitude, but I am not shouting to close all coal power stations either.
Now you can call me a Troll, or Tom P with no papers, or denigrate what I am saying anyway you like, but the problem you have is that on this issue, I am right.
“the chain of evidence”
Can you specify the “links” in said chain?
Andrew
Nathan’ logic:
bad science is ok if supports “action”.
Only problem is that bad science leaves you not knowing what the heck it is you’re up against. How will you know when “action” is working,if you’re operating off a flawed model?
Nathan: “action” is not a yes/no question.
Don’t be a “goose”.
;
I don’t know why I’m bothering to defend CA but I’m tired of the way things keep getting twisted around.
Nathan, I’m not trying to be offensive, but when you believe something regardless of evidence to the contrary that is a form of bigotry. Steve started his audit based on an interest in the statistics and whether Mann’s reconstruction was valid mathematically, not to prove or disprove climate change (which he has repeatedly stated he believes in. Try reading his blog roadmap here. Stop letting you’re own prejudices prevent you from understanding the positions others have taken.
Nathan said “”My whole argument is there is a case for action without the Hockey Stick. I am not alone on this blog in that belief (See Lucia above). Steven Msoher points it out best here:
“In anycase I think the MWP is so far down the chain of evidence that it baffles me why people even argue about it…â€
I brought this up at CA for this exact reason. I was baffled why CA has continued for 10 (?) years to focus on proxy reconstructions, when they are really pretty low hanging fruit in the whole let’s act on climate change tree.””
For those who think the MWP is non-essential to IPCC AR4, you are incorrect. This can be determined in Chapter 9. The argument that the CI need to go to +/- infinity is a strawman. The accuracy and precision of the “Hockey Stick” is needed because of the way AR3 and AR4 are written. Yes, they could have been writtem different. The IPCC authors didn’t. This is another strawman. They were written as they were.
There were two problems. One problem was that there is natural forcing. If the natural forcing is too large, CO2 has to be small for current conditions. Thus the IPCC concluded that natural was small. This causes a problem with sensitivity. If the climate is too sensitive, the temperatures expected would be much more than could be accounted without negative feedback. Positive is assumed, or we need not worry since most agree CO2 by itself would result in 1C for a doubling. SInce CO2 has to be the major forcing, water is positive, and the climate cannot be too sensitive, the “golden” Mauna Loa data bounds the climate sensitivity. Thus the shaft HAS to be without a large MWP, and the blade MUST be “unprecedented.”
Without this, IPCC AR3 and AR4, cannot claim to be both robust and very likely. The IPCC would be in the position of saying we are very sure that CS for doubling is between 0.38C and 6C, or there is a 50:50 chance that it is 3C. For .38C and only a 50:50 the requirement of doing something because of AGW, much less CAGW, could be ignored.
The problem according to AR4 chapter 9, Attributing Climate Change, is climate sensitivity where they say
“An alternative approach, which has been pursued in most work reported here, (the other work is agreed to be too restrictive or “naive”, by itself) is based on varying parameters in climate models that influence the ECS (equilibrium climate states) in those models, and then attaching probabilities to the different ECS values based on the realism of the corresponding climate change simulations. This ameliorates the problem of feedbacks being dependent on the climatic state, but depends on the assumption that feedbacks are realistically represented in models and that uncertainties in all parameters relevant for feedbacks are varied. Despite uncertainties, results from simulations of climates of the past and recent climate change (Sections 9.3 to 9.5) increase confidence in this assumption.””
Note that they have to use past and recent climate change in order to justify the confidence in this assumption. The assumption is, pay attention Nathan, Raven, Mosher(??? In anycase I think the MWP is so far down the chain of evidence that it baffles me why people even argue about it… did you say this??) that “”uncertainties in all parameters relevant for feedbacks are varied,”” and are REALISTIC!! ALL possible parameters relevant for feedback, it also means uncertantities are defeined or bounded, and they must be realistic. What is realistic, is it a MWP and a LIA, or a straight shaft? So what influences feedback, according to AR4, “”However, the climate’s sensitivity to external forcing will depend on the mean climate state and the nature of the forcing, both of which
affect feedback mechanisms.””
But the IPCC cannot establish mean climate state, the nature of the forcing, or ALL RELEVANT (MWP would indicate a relevant parameter concerning natural forcing and feedback) parameters without reconstructions including at least 7 centuries, according to IPCC Chapter 9, Attributing Climate Change. Damn end of MWP is that 7 century mark. Wonder why they didn’t say 1000 years or more? Mann did. Well if the LIA is too deep, it has the same effect as MWP being to high. Imagine that. 😉
By the way, IPCC said mankind’s GHG’s, mainly CO2, did it., in case you didn’t read it. 😉
Perhaps this is NOT realistic, courtesy of Chapter 9 AR4, IPCC.
“How do you account for the Team addiction to flawed proxies..”
One of these days, I’m going to get around to finding out the real deal on Bristlecones pines. I have a feeling that they aren’t as good as Mann et al say, but not nearly as bad as people at CA say. For one, the reason the NRC said to avoid strip bark bristlecone pines is because they are sensitive to CO2 fertilization. Mann (and a few others) contend that the influence of CO2 can be removed (because it is a steadily increasing factor and should be more straightforward to account for.) Then there’s the question of how many cores actually come from strip bark samples and how many are full bark. (If anyone has any info on this, please point it out to me.) Then there’s the question of how heavily the strip bark samples weigh in the recon. CA says tons, Wahl and Ammann say not so much.
I seem to remember a CA post by Rob Wilson wherein he implied BCP were a mediocre proxy–not great, kinda “meh”.
Boris,
.
As far as I know there are no biological studies that demonstrate the required linear sensitivity of BCP to temperatures. This means that anyone who claims that they are good temperature proxies is not making a claim based on evidence – it is simply an opinion (most likely wishful thinking because their long lifespan makes them extremely useful data source if such a relationship existed).
Bender
You had a chance to demonstrate your oint about Broecker (2001) all I see is a big fail.
“Nathan’ logic:
bad science is ok if supports “actionâ€.
Only problem is that bad science leaves you not knowing what the heck it is you’re up against. How will you know when “action†is working,if you’re operating off a flawed model?
Nathan: “action†is not a yes/no question.”
I never said that. I said the Hockey STick is irrelevant to the action case. Heck if Lucia and Steven Mosher see a case for action it is no me, that is the goose. The question, since 1988, has never been whether we’d be taking action. It’s only ever been a question of how much.That’s where the debate is; and of course I can see that better science means better targets. But I am not sure that improving proxy reconstructions will lead to better understanding in terms of what targets to set.
I see John F Pittman decided to debate that point – I’ll look at what he says.
John F Pittman
I don’t think I am capable of debating this with you, but
“There were two problems. One problem was that there is natural forcing. If the natural forcing is too large, CO2 has to be small for current conditions. Thus the IPCC concluded that natural was small. This causes a problem with sensitivity. If the climate is too sensitive, the temperatures expected would be much more than could be accounted without negative feedback. Positive is assumed, or we need not worry since most agree CO2 by itself would result in 1C for a doubling”
I thought positive feedback was assumed because of our understanding of paleoclimates – given that most of the Phanerozoic was much hotter than now (and that the sun is presently pretty close to as hot as it has been and was cooler in the past). Isn’t it necesarry to have positive feedbacks to explain this?
“But the IPCC cannot establish mean climate state, the nature of the forcing, or ALL RELEVANT (MWP would indicate a relevant parameter concerning natural forcing and feedback) parameters without reconstructions including at least 7 centuries, according to IPCC Chapter 9, Attributing Climate Change.”
I think you are placing a lot of heat on just the MWP (pun intended) – I don’t see why the MWP becomes THE most important time period for these calculations. Why can’t we use the last glacial maximum for example? Or the Holocene Optimum? These are known global events, and they mention in there that they use them in the modelling. Is the MWP somehow special?
Can you get as hot as it was at the peak of the previous interglacial without having a positive forcing?
It sounds to me like a lot of people here think the MWP was as hot or hotter than know, when really no one knows.
Jeff Id (Comment#22135) October 20th, 2009 at 8:30 am (Previous thread)
Thankyou for linking to your very interesting posts. Needless to say I have several disagreements with them, and have left comments on several of your threads:
http://noconsensus.wordpress.com/2009/06/20/hockey-stick-cps-revisited-part-1/#comment-11122
http://noconsensus.wordpress.com/2009/06/23/histori-hockey-stick-pt-2/#comment-11123
http://noconsensus.wordpress.com/2009/08/26/more-on-cps-signal-distortion/#comment-11125
As relevant to Lucia’s original blog, however, I think your work shows that a CPS technique will recover an original signal, even though that signal may be distorted. In other words, using the CPS technique will not generate a hockey stick shape unless either the shape is in the data, or the Signal to Noise Ratio is very low. In the later case, the shape generated will not be a genuine hockey stick, but rather more of a putter. There will a valley immidiately preceding the calibration period, and before that the graph will follow the mean of the calibration period. Further, with a low SNR, the “blade” will have a low slope, much lower than that of the calibration data. None of these features is characteristic of CPS reconstructions. On the contrary, in CPS reconstructions, the “blade” tends to have a similar slope to the calibration data; there is no distinct valley immediately prior to the calibration period, and the “stick” tends to lie below mean of the calibration period, and to have significant variance, even with a high number of proxies.
All of these features suggest a significant signal has been recovered by CPS reconstructions. Of course, the signal will have been distorted by the CPS, though how much is a matter of dispute. See, for example here:
http://www.meteo.psu.edu/~mann/shared/articles/MRWA-JClimate05.pdf
and figure S12 here:
http://www.pnas.org/content/suppl/2008/09/02/0805721105.DCSupplemental/0805721105SI.pdf#nameddest=STXT
However, while the graph lows below the mean of the calibration period, the effect you have identified causes the CPS technique to overstate warming and to understate cooling. That means actual signal partially recovered by CPS reconstuctions are likely to show a cooler MWP than do the CPS reconstructions themselves. The CPS techniques may bias the reconstructions, but in the opposite direction to that claimed by AGW sceptics.
Only problem is that bad science leaves you not knowing what the heck it is you’re up against. How will you know when “action†is working,if you’re operating off a flawed model?
All science is ‘bad’ science. From the Principia Mathematica to Eienstiens Theory of Relativity, there are gaps and errors. Science progresses.
Bugs
youv’e misunderstand ‘bad science’. You have mistaken goood science which is on-going for bad science which is science done badly. IE not on method.
Nathan, your point though it may be valid, is not what AR4 Chapter 9 says. The AGW faced two problems. One is that it was known to warm before CO2 could be a major player. Since we had temperature only a short period of time, AGW faced a problem of knowing climate senstivity. In order to get an answer, they had to make an assumption. However, once they made that assumption, they needed some other proof, or it would be as critics, I believe it was Christy, or Lindzen pointed out: a circular argument. What they used was 700 years from present, with decadal climate resolution or better. In other words, tree ring reconstructions. This is what they state in Chapter 9.
You say that “It sounds to me like a lot of people here think the MWP was as hot or hotter than know, when really no one knows.” We know from timberlines, sea levels, and historical data that the MWP was warm, and was considered near the Holocene Optimum until MBH98, which would put MWP about 1.5C to 2C warmer than the CWP. One of the “findings” was MWP was Northern hemisphere only, based on Mann’s work. Until then the MWP was assumed world wide.
If MWP was world wide, and hot, then the LIA would be deeper and the models would not necessarily match the reconstructions well enough for the IPCC to claim the complementary nature of reconstructions and the models resulting in reduced confidence. Translation, could not claim AGW very likely. Also, since, the assumption was that CO2 caused most of the heating since about 1960, changing would mean that critics could claim it was natural, or that water vapor feedback was near or negative with CS at 0.75C or so supporting Schwartz, Choi and Lindzen.
I agree with you, perhaps some other work would be better. However, that is not what AR4 used in Chapter 9: Understanding and Attributing
Climate Change.
In keeping with this thread, perhaps they cherry picked which reconstructions to use, and that is why chapter 9 was written this way. 😉
Boris says:
“One of these days, I’m going to get around to finding out the real deal on Bristlecones pines. I have a feeling that they aren’t as good as Mann et al say, but not nearly as bad as people at CA say.”
The “real deal” is not known. Ababneh’s resample does not match Graybill’s. Yet Graybill (the one NAS said not to use) is used in recons instead of Ababneh’s. No one has ever explained why the Ababneh sample appears normal (no wacky uptick at the end of the series) and the Graybill is so abnormal.
Nathan says:
“the Hockey STick is irrelevant to the action case”
Yes, we know. You keep asserting this. I guess you are incapable of understanding John F. Pittman’s counter-argument?
Nathan says:
“I don’t think I am capable of debating this with you”
Agreement.
“If the natural forcing is too large, CO2 has to be small for current conditions.”
Huge logical fail, John. You are assuming that if natural forcings are large then they must have contributed to later 20th century warming. But in fact, natural forcings could be currently negative and masking some of CO2’s warming.
If you think that natural variation is higher than currently estimated, all you are doing is widening the error bars on 20th century observational estimates of CO2 sensitivity. That’s it.
John,
You say: ” We know from timberlines, sea levels, and historical data that the MWP was warm, and was considered near the Holocene Optimum until MBH98…”
I refer you to H.H. Lamb 1965 (“The Early Medieval Warm Epoch and its Sequel), second page, second paragraph:
“Nothing suggests that the warmth of the early medieval period attained that of the climatic optimum…”
In the same paragraph, incidentally, he notes that “world sea level was hardly affected”.
I don’t know where your impression of what was “known” before MBH98 comes from, but it’s evidently not from Lamb. Besides, whatever evidence existed pre-1998 still exists today, so if a robust case can be made from it for a global MWP of the magnitude you suggest (or, indeed, of any magnitude globally) then it is there to be made. I have not seen it done.
Boris, I think by “large” he meant large *and* positive. Otherwise, good catch.
Simon Evans,
It is good to be very careful about this point.
.
The strongest evidence for very warm MWP (Vikings in Greenland, grapes in England, lack of glaciers in Alps, etc.) all comes from the North Atlantic. That’s why Broecker’s (2001) article is interesting. He (nominally) tries, but fails, to argue that the MWP was “global”. But he makes a case that – because of its alleged source, the THC – it did have a very wide reach. In fact, that is not inconsistent with the assertion that it was mostly NH.
.
The MWP was the most recent of six warm cycles coming off of the HTO, which was global (any evidence to the contrary?). The LIA was the most recent cool phase. Under this hypothesis, the North Atlantic should be experiencing a natural warming cycle of unknown origin, but somehow linked to the THC. The global effect of GHGs would then be layered on top of this regional (North Atlantic) effect.
.
This is why it would be helpful to know the magnitude of these THC-related background oscillations – because we are supposedly in a warm phase of the 1500-year THC cycle right now.
bender (Comment#22491) October 25th, 2009 at 8:12 am
I am curious how you support the last statement. If the THC is behaving completely differently, how is that consistent with a local/NH-only effect?
Bender and Boris good catch. Except the natural forcing is assumed to be large and positive with the presence of increased CO2. In particular water vapor. I thought that “feedbacks are realistically represented in models and that uncertainties in all parameters relevant for feedbacks are varied” and that the IPCC assumption that water vapor feedback is positive and large, would preclude your comment of the large logic hole. Would the IPCC consider “But in fact, natural forcings could be currently negative and masking some of CO2’s warming?” I don’t think this is within IPCC’s stated conclusion that water vapor is large and positive.
Further you state “”If you think that natural variation is higher than currently estimated, all you are doing is widening the error bars on 20th century observational estimates of CO2 sensitivity.” My “Thus the IPCC concluded that natural was small” was poorly worded. It should have been about natural variation or forcing without CO2. Sorry. I think “all your are doing is widening the error bars…” is misunderstanding how the IPCC used the reconstructions. They were used such that they could claim realistic establishment of the mean climate state. Without this they cannot support the claim of robust and very likely. So widening is not all that happens in the methodology of Chapter 9.
On the question of how warm was the MWP. Having heard about it for about 45 or more years, I would say I have seen many different estimates and the only one I agree with is that it most likely was warmer because of the discovery of fossil trees and treelines around the world, especially in the northern hemisphere that indicate we have not been as warm as long, since the biota has not re-established itself in these areas. Data from the SH seem problematic. It maybe I just have not seen a good definitive study.
oliver asks:
“how is that consistent with a local/NH-only effect?”
I specifically said “regional” and previously used the phrase “far-reaching”. So I don’t know where the word “local” came from. I didn’t say it was NH only. I said it mightn’t be inconsistent with the idea that the strongest warming was primarly NH. I am not married to this proposition at all. If you have evidence otherwise, be my guest.
Bender,
I don’t know if these are acceptable “proof” of a global MWP or if the source is considered reliable, but what’s you’re opinion?
global MWP
bender (22491),
Sure, we can hypothesise about what might have explained a supposed global MWP, but then we could also hypothesise about what might have explained a supposed regional MWP. I’m not sure where this gets us to in itself!
Meanwhile we have reconstructions which compare supposed MWP temperatures with current temperatures. Loehle 2007, for example, reconstructs from 18 primarily NH and land based proxies and compares to the global current average, concluding with a suggestion of temperature comparison. This is simply risible. If you wanted to compare apples with apples you would at least take an average of the instrumental temperatures from the same 18 locations (which would throw up a temperature anomaly notably higher than the current global average, I posit).
There are some who are ready to critique every aspect of the hockey team’s work whilst accepting entirely unsceptically any indication of MWP-ness shown elsewhere. It is pretty revealing of ‘motives’, which some are fond of mentioning only when suggesting that the motives of Mann et al could possibly be held to account.
John (22495),
Water vapour is not a forcing.
Agreed, Simon. I was merely trying to show that I’m not dead against the idea that the MWP was just a MCA. It matters quite a bit what’s happening in the SH and Broecker (2001) himself mentions a cooling Antarctic during the MWP. Apples to apples. Always.
Simon Evans (Comment#22501)-
“Loehle 2007, for example, reconstructs from 18 primarily NH and land based proxies and compares to the global current average, concluding with a suggestion of temperature comparison. This is simply risible. If you wanted to compare apples with apples you would at least take an average of the instrumental temperatures from the same 18 locations (which would throw up a temperature anomaly notably higher than the current global average, I posit). ”
Why such criticism is exclusively reserved for Loehle is beyond me. Virtually all studies have been reliant on a small number of proxies in mostly Northern Hemisphere locations, mostly on land. It’s not quite that the number of Southern Hemisphere Ocean proxies could be counted on one hand, but pretty close.
Ah well, Long ago on this thread Jeff Id showed how CPS will distort a known signal in simulated proxy data. I’ve just finished ( almost) reading a thesis by Briffa co author Melvin. Some salient points for the cherry picking argument. Melvin demonstrates how RCS ( used on the yamal series) puls a hockey stick ( replete with a LIA and depressed MWP) out of synthetic tree ring data with NO SIGNAL in them. It has to do with the method RCS uses to remove the age related growth signal.
But more importantly Melvin concludes his study with this:
“Expected growth curves are used to remove the age-related growth trend from series of measures. Testing that the age-related growth trend has been removed from series of tree
indices is often performed by examining mean indices aligned by calendar year for different classes of tree. In this thesis testing the presence of age and diameter related bias in tree indices is examined by aligning tree indices by age or diameter for different classes of tree. These methods were used to show that the standard RCS method produces series of tree indices with systematic age and diameter related biases which can seriously
distort the modern end of resultant chronologies.”
Now the bias happens to be a 10% uptick in the modern period. By using a RCS standardization proceedure ( like on Yamal) you distort the modern chronology. It would seem to me that if you want to pick cherries ( chronologies that correlate with the modern instrumented series) one should not use a standardization methodology that is know to distort the modern era. That’s picking lemons.
Simon Evans (Comment#22459) October 24th, 2009 at 3:16 pm
Steven (mosher),
” I am disinclined to think that continuing regardless to pump GHGs into the atmosphere is a very smart idea, even though we may not be certain in agreement as to the projected impact of doing that. What do you think?”
I think I would say something stronger than that. The AGW or more precisely the CAGW crowd believes that uncertainty leads to inaction. I think we ALWAYS act under uncertainty. Do GHGs lead to a warmer future? Yup. Is it a good idea to pump them willy nilly into the atmosphere? Nope. What do I think a good target is? I actually like a methodology proscribed by Ross Mc which ties a tax ( control) to a measurable system output ( tropospheric temps) And like most lukewarmers support nuclear, solar, wind. And measures to prevent harm ( limited coastline building etc )
I’ve just finished ( almost) reading a thesis by Briffa co author Melvin. Some salient points for the cherry picking argument. Melvin demonstrates how RCS ( used on the yamal series) puls a hockey stick ( replete with a LIA and depressed MWP) out of synthetic tree ring data with NO SIGNAL in them. It has to do with the method RCS uses to remove the age related growth signal.
But more importantly Melvin concludes his study with this:
“Expected growth curves are used to remove the age-related growth trend from series of measures. Testing that the age-related growth trend has been removed from series of tree
indices is often performed by examining mean indices aligned by calendar year for different classes of tree. In this thesis testing the presence of age and diameter related bias in tree indices is examined by aligning tree indices by age or diameter for different classes of tree. These methods were used to show that the standard RCS method produces series of tree indices with systematic age and diameter related biases which can seriously
distort the modern end of resultant chronologies.â€
So all you are saying is that the scientific process is working as normal, and all the ‘most quietly disturbing’ nonsense is irrelevant, as usual.
Because I was raised to speak this way, let me state that I would be leary of proclaiming the MWP a regional only warming.
Simon Evans says “Sure, we can hypothesise about what might have explained a supposed global MWP, but then we could also hypothesise about what might have explained a supposed regional MWP. I’m not sure where this gets us to in itself!” From Chapter 9, one of the implicit and also staed assumptions is that ” This ameliorates the problem of feedbacks being dependent on the climatic state, but depends on the assumption that feedbacks are realistically represented in models and that uncertainties in all parameters relevant for feedbacks are varied. Despite uncertainties, results from simulations of climates of the past and recent climate change (Sections 9.3 to 9.5) increase confidence in this assumption.””
If the MWP was just in the NH, then the IPCC statement “that feedbacks are realistically represented in models and that uncertainties in all parameters relevant for feedbacks are varied. Despite uncertainties, results from simulations of climates of the past and recent climate change
(Sections 9.3 to 9.5) increase confidence in this assumption,” one would have to show that realistic models show warming in NH but not in SH. AT present the claim for models is “No climate model that has used natural forcing only has reproduced the observed global mean warming trend or the continental mean warming trends in all individual continents (except Antarctica) over the second half of the 20th century.” Which would indicate that cooling will not occur in the SH if the NH heats up. I recognize that there is a logic gap. However, since the IPCC did not address SH cooling relative to NH at the levels indicated for MWP, I would urge caution on both sides about “going a bridge too far.”
bender (Comment#22466) October 24th, 2009 at 5:20 pm
yes it boggles the mind. If you want to destroy the anti hockey stick argument the best way is to do a reconstruction that eliminates all the suspect series. You don’t defeat the anti stick argument by switching from one suspect series to another. you dont defeat it by putting in 3 suspect series and then showing you are robust if you remove one of them. its retarded argumentive structure. Sure its sly, it gets by casual review. But in terms of motivation the approach is …. what? I can’t think of a GOOD motivation for this argumentative approach. When somebody does a recon without suspect series THEN you get an interesting starting point for subsequent arguments about the individual series.
Sure its sly
You have an obsession with this type of thinking.
Raven (Comment#22467) October 24th, 2009 at 5:22 pm
“The MWP is far down the chain of evidence for AGW but it is extremely important for CAGW because CAGW requires that one believe the climate models accurately represent the climate system. If the MWP was real and hot then that claim would be much harder to make.”
I’m not so sure. If there was a large MWP that could indicate LTP and/or a climate more sensitive. If you have a LTP at work with long period ups and downs you better damn well be MORE careful about adding GHGs. Think of it this way. If the MWP is indicative of a LTP or cycle what part of that cycle are we in?
A: the up part and the warming is “natural”
B: the down part and the warming is anthro and worse than
we think.
Or is the MWP evidence of a LTP at all?
What surprises me is that few on the AGW side can see that an elevated MWP might actually play to their argumentative advantage. Same with leif svalgaards work.
bugs (Comment#22511) October 25th, 2009 at 5:41 pm
“Sure its sly
You have an obsession with this type of thinking.”
I’m a scorpio, of course I do. I’m a trained sophist, of course I do.
I do marketing, of course I do. I used to build war simulations, of course I do. I recognize my own.
steven mosher says “What surprises me is that few on the AGW side can see that an elevated MWP might actually play to their argumentative advantage. Same with leif svalgaards work.” The way that the IPCC bounded their claims of very likely and robust depends on water vapor being a large positive feedback. With CS larger, one would have to have water neutral or negative. At that point “heat in the pipeline may disappear, and the 60% warming that should have occured has, thus a doubling of CO2 would be about 1C. With a larger natural total forcing, recent flat trend could indicate that a doubling is not much more than 1F. I don’t think this is what would thrill the IPCC.
bugs (Comment#22434) October 24th, 2009 at 5:47 am
“I met a climate researcher once. I asked him what he thought of people like you. For him and his colleagues, you are completely irrelevant, and not worth a seconds thought. You are not part of the scientific process, you do not understand what they do, you will, however, believe various nonsense if it confirms you prejudices. The research progresses, they do their job.”
Hmm. I had the pleasure of talking to several climate researchers. They actually thanked me for the efforts to get hansen to release the GISS code. If you want to know my position on things it’s pretty damn easy: free the data, free the code. That’s it in a nutshell. Everything else is open for debate and I’m open to being convinced. Now, since we started this effort in 2007 to get more data transparency and code release we are seeing some good movement from those researchers who are “ignoring” people like me. maybe they are doing it on their own. cool. Maybe they are ignoring “people like me” Fundamentally, if more data is released and more code is released then I’m happy. You should be happy too.
bugs (Comment#22507) October 25th, 2009 at 5:10 pm
“So all you are saying is that the scientific process is working as normal, and all the ‘most quietly disturbing’ nonsense is irrelevant, as usual.”
Actually not. The Yamal series which was standardized using this RCS process has just been used (2009) in a paper published by SciAmerican. If science was working a finding of bias in a method ( like RCS) would lead to a situation where researchers got off that crack. Same for the Phd thesis which resampled bristlecone pines. The result is well nigh buried and strip bark series continue to be used.
Lets say I build bridges for a living. In building bridges I use engineering models to specify construction standards. Now lets suppose that after some bridges are built some bright person discovers a limitation in models. Researchers investigate and improve the models. Question: what do you do with old bridges built according to the old models. Do you just move on?
Boris (Comment#22476) October 24th, 2009 at 9:25 pm
there is also a mechanical problem with strip bark, I believe. bender knows more , mr pete, etc.
As the science has progressed since the start of all this I think there is ample justification to bring as many proxy series up to date as possible. Its not like the case with the historical temperature series where the data is what the data is, warts and all.
I’m a scorpio, of course I do. I’m a trained sophist, of course I do.
I do marketing, of course I do. I used to build war simulations, of course I do. I recognize my own.
Speak for yourself. You are projecting.
Just a comment on the impact of the solar cycle. From here:
http://zebu.uoregon.edu/~soper/Earth/earthtemp.html
I got the formula for temperature and the amount of solar irradiance in watts per square metre.
Just trying two numbers for solar irradiance that are 1 watt apart, 220 and 219, I get a difference of .28 degrees. Now, this may be too precise, as the numbers may vary too much for it to be measured that accurately, and we only have sigma accurate to one decimal place and so on.
But if the physics are close to right, 1 watt of difference in solar irradiance *could* reduce global temperatures by the same amount as they were expected to rise over the period 2001 to 2009 (roughly .2 of a degree centigrade). As 2000 was solar maximum, and in 2009 we are at solar minimum (indeed, solar minimum was reached 2007, and has lasted a long time) it *might* be all of the explanation required.
If I can find other solar minimums and maximums, I will have a look to see if there was any impact on global temperatures.
David Gould (Comment#22524)-the peak to trough amplitude of the solar cycle’s temp impact is pretty well established to be a tenth of a degree. Even if a decade started at the solar max and ended at the min, the most warming the cycle could counter would be half the “expected” rate. In fact, though, the last solar min was in 1996, and the recent one may have occur in late 2008:
http://en.wikipedia.org/wiki/List_of_solar_cycles
The trend between 1997 and now, which pretty well accounts for the expected fast response, is zilch in Hadcrut.
Andrew_FL,
Could you provide a link to information on the above?
“Satellite radiometer measurements made over the last 20 years have shown
that total solar irradiance varies 0.1 percent over one 11-year sunspot cycle,
but that irradiance varies considerably with the wavelength of the electromagnetic
radiation (Lean and others, 1995a). The variation of 0.1 percent in
total solar irradiance over one sunspot cycle translates to a global tropospheric
temperature difference of 0.5° to 1.0°C (Labitzke and van Loon, 1993).”
Obviously, the troposphere is not the surface. But .5 to 1 is relatively large. I wonder what the effect on the surface is?
Pittman,
Again, on the money. If the models don’t produce a THC, how credible are they? (Heck they don’t even get average GMT correct!)
http://www.phy.cuhk.edu.hk/sure/comments_2007/mwyau_rep.pdf
The above is some stuff on the surface temperature. And I looked at a 2008 thread on this very board, which talked about the .1 degrees mentioned in the IPCC report.
So it looks like surface temperature response is somewhere between .06 degrees (used in many GCMs) from solar maximum to solar minimum and just under .2 degrees (that was from some 2007 research mentioned in the paper sourced above).
Therefore, my calculation of .28 degrees is very high and thus wrong.
I should point out, though, that for a slope of .2 degrees per decade, there should have been less than .18 degrees thus far from the start of 2001 (we have not quite had nine years). So, .1 degrees from solar maximum to solar minimum accounts for more than half of the missing temperature increase.
The 2008 thread suggested that statistically this meant that the slopes no longer falsified the claim of .2 degrees per decade on the GISS data. I am not sure about Hadley, however.
Bender,
You have some sort of problem with dominance don’t you.
“Yes, we know. You keep asserting this. I guess you are incapable of understanding John F. Pittman’s counter-argument?”
You are a goose. You took days and days arguing nothing, being completely incapable of explaining why the MWP is important, and then Mosher indicates that he doesn’t see it as important, and then at the last moment you jump onto John F Pittman’s argument that the MWP is somehow critical to our understanding of climate sensitivity… wacky.
Yet in the AR4 the IPCC say their understanding is from the Holocene Optimum and from the peak of the previous interglacial, both known global events. John F Pittman, would the Holocene Optimum and Last peak interglacial have been as warm using your figures?
David Gould (Comment#22530)-Some of those studies you mentioned are pretty old but I see at least you managed to find the more recent info. The troposphere signal is also smaller than suggested by those old papers.
A recent reference which you might regard as favorable:
http://pubs.giss.nasa.gov/docs/2008/2008_Lean_Rind.pdf
“Solar activity is reliably detected in the global
historical surface temperature record, for example, producing
a peak monthly increase of 0.17 ± 0.01 K from April
1996 (solar minimum) to February 2002 (solar maximum).
The 13-month running mean solar cycle change is 0.11 K at
one month lag, consistent with the solar cycle signal found
in lower troposphere satellite data since 1979 [Douglass and
Clader, 2002].”
Nathan (Comment#22534)- “Yet in the AR4 the IPCC say their understanding is from the Holocene Optimum and from the peak of the previous interglacial, both known global events.”
Huh? Last I checked, IPCC just looked at a bunch of models then cited literature (by modelers) that claimed that their sensitivities were “proven” by the paleo record. All such studies make a rather large number of assumptions that are dubious at best
Andrew_Fl,
That 2008 paper that you linked to, while making reference to other research, comes to the conclusion that .1 degrees is most likely the correct figure.
Nathan says:
“incapable of explaining why the MWP is important”
I explained it. You don’t read. Good luck in life.
Bender,
“If the models don’t produce a THC, how credible are they? ”
Tetra-Hydra-Cannabinol???
Not at all I say!!
bugs (Comment#22523) October 25th, 2009 at 6:26 pm
(quote from Mosh, replying to bugs claim that he has an obsession with “sly”):
“I’m a scorpio, of course I do. I’m a trained sophist, of course I do.
I do marketing, of course I do. I used to build war simulations, of course I do. I recognize my own.”
Speak for yourself. You are projecting.
Bugs, I have to ask in all seriousness, is English your native language???
Bugs, I have to ask in all seriousness, is English your native language???
The statement is quite simple. He thinks he can attribute motivations to other people based on what he thinks of himself. He is “projecting” his thoughts onto others. Not literally, but effectively. He thinks ‘x’, therefore person ‘b’ thinks ‘x’ because he has identified person ‘b’ as having the same personality.
Bugs.
I like to pull the legs off bugs. It’s kinda funny. Bugs. stop stalking me. Or I’ll pull your legs some more.
bugs (Comment#22541) October 25th, 2009 at 11:22 pm
Actually bugs it works like this. After you spend years around arguments and talking to the people who make them you understand that the argumentative style is a PROXY for the persons personality. For myself I don’t like the sly approach to argument, because I am not sly. I like the ball busting approach, where I stipulate to all your objections and then still show you how you are wrong. Or the judo approach where I accept all your premises and show how they lead to the opposite conclusion.
As with all proxies they can be noisy and sometimes inverted.
steven mosher (Comment#22543)
Actually bugs it works like this. After you spend years around arguments and talking to the people who make them you understand that the argumentative style is a PROXY for the persons personality. For myself I don’t like the sly approach to argument, because I am not sly. I like the ball busting approach, where I stipulate to all your objections and then still show you how you are wrong. Or the judo approach where I accept all your premises and show how they lead to the opposite conclusion.
As with all proxies they can be noisy and sometimes inverted.
You can tell a someones personality just like that? Amazing. Have you ever had these powers tested? I would like to see the results.
Steven Mosher #22512:
I think it is interesting to wonder whether the existence of the MWP as evidence of a climate system given to large swings could ground an argument that adding forcings to one extreme state or the other may produce amplified adverse results.
However, that is the how the MWP has ever been presented. It was a notion that (a) pre-existed CAGW; (b) was perceived as antithetical or at least inconvenient to the marketing of CAGW and (c) after Mann’s hockey stick achieved iconic status and then came under attack for its demonstrably half-assed methodology, the CAGW camp made denial of the MWP an element of orthodox dogma. The elimination of the MWP fattens the handle and preserves the purity of the blade.
The belief in the models for some is so complete that some participants in this thread (and its predecessor) assert that the MWP cannot have existed because it would require “imaginary” forcings, i.e., conditions not included in the models. This exemplifies quasi-religious nature of CAGW in which the only real test of data or any hypothesis is whether it helps or hurts The Cause.
I am less wedded to a particular vision of the MWP with respect to geographic scope, amplitude and duration than I am opposed to the perverse ideological approach to climate science that CAGW spawns and for which the MWP has become a battleground.
I can’t stand the thought of scanning Nathan’s spew looking to see if he thanked John F Pittman yet for making it abundantly clear why MWP “matters”? Has Pittman been thanked by Nathan?
.
I had composed a note thanking John F Pittman for putting the flesh on my two-sentence summary for Nathan. (It’s quite a bit of work to compose those 3-4 paragraph replies.) But I decided not to post it, thinking that would be obtuse. Shoulda known I’d need something big and blunt to pound the point through Nathan’s foggy gray.
.
But it doesn’t matter. All facts point to “action”.
.
It’s good to know that bugs can’t tell good science from bad. It lets us know what level he’s working at.
.
What on earth are people like Nathan and bugs doing at a technical blog such as this?
.
Can we agree that cherry-picking (getting back to the OP) is bad science, and that we just won’t tolerate it? Can we agree that really bad science (and, bugs, I mean BAD) undermines the case for action?
Ryan O implores Nathan to “read more, post less”. Who could disagree?
.
I decided to pull out my reply to Nathan on the importance of MWP. It’s 4 days old, and precedes Pittman’s nice contributions.
………………………………………………………………
bender (Comment#22301)
October 22nd, 2009
Nathan’s underlying question seems to be this:
‘Why would anyone try to disappear the MWP if this would have no implications for climate sensitivity?’ He can’t see the connection, so he’s trying, first, to understand what might be wrong about either side of the equation. And second, to clarify any connection that might exist.
.
The answer – the connection – is that the alarmist call to action hinges on more than one assertion. First, that current temperatures are already alarmingly high; second, that they will continue to rise higher. The first is dependent upon the magnitude of the MWP. The second is dependent on the climate sensitivity calculation. The magnitude of MWP is not strongly connected to the climate sensitivity calculation*. The link between them is more political than scientific.
.
*But see my related argument at CA, along the lines of Raven’s bit on intrinsic natural variability.
………………………………………………………………
For Nathan to suggest that what I write is at odds with what Pittman says indicates his lack of attention or reading comprehension. No one will be surprised at this. Still, it is sometimes worth pointing out why some people merit the designation: “ass”. Nathan, when someone puts an asterisk on a statement, it means “this is a tangential point, but one not to be ignored”.
Nathan says:
“You are a goose. You took days and days arguing nothing, being completely incapable of explaining why the MWP is important”
.
Let the record show that I answered instantly and fully, and nicely I might add. The irony is Nathan going on for “days and days” about nothing. 4 days, to be exact.
.
When your agenda is action-damn-the-facts, it’s amazing what facts you will overlook.
Andrew_FL (Comment#22503)
“Why such criticism is exclusively reserved for Loehle is beyond me. Virtually all studies have been reliant on a small number of proxies in mostly Northern Hemisphere locations, mostly on land. It’s not quite that the number of Southern Hemisphere Ocean proxies could be counted on one hand, but pretty close.”
No such reservation from me, Andrew – I’ve already said that I don’t think we have good enough evidence either way. I agree with your comments on the limited coverage of SH proxies (and so, I think, would Michael Mann!).
Getting back to cherry-picking, I trust that we can all agree that the cherry picking of individual proxies on an a priori basis of their either showing a pronounced MWP or showing a lack of one is entirely disreputable. If it’s ever clear that has been done then let ‘both sides’ speak out against it. Show me where you think that has been done, if you wish. For my part I’d be likely first to refer you to Monckton’s ‘presentations’.
Simon, surely you are following the Briffa threads at CA?
A search of the phrase “pick two” at Climate Audit will reveal several discussions about Michael Mann’s method of picking weather station data to align with proxy data … which wouldn’t be so bad if he adjusted his benchmarks to allow for that loss of a degree or more of freedom. This is cherry-picking, pure and simple. Look at his code. The function that does the cherry picking of proxies is called “propick.m”.
.
But what’s the problem? Esper et al. (2003) told us that “the ability to pick and choose which sites to use is an advantage unique to dendroclimatology”. Apparently that advantage applies to glacioclimatology and geoclimatology as well.
bugs (Comment#22544) October 26th, 2009 at 1:02 am
“You can tell a someones personality just like that? Amazing. Have you ever had these powers tested? I would like to see the results.”
you just did.
[Use Nelson’s voice from Simpsons]
Ha ha!
bugs without legs
George Tobin (Comment#22545) October 26th, 2009 at 7:22 am
I’m going back and doing some more reading of Pittman and bender . then onto primary texts. I’ve tried to keep a hedgehog focus on the data availablity, code availability, GMST question to the exclusion of everything else. So MWP? does it matter? Well, not to me in the sense that I don’t think it absolutely swings the case one way or the other. But house of cards being what they are perhaps it does matter. So, I’ll read up some. Primary texts only so if folks have reading lists I’m all eyes.
Bows.
bender,
There are different kinds of picking! If it can be demonstrated that Briffa picked Yamal because it showed a HS rather than for other reasons, then I will join with those who call it fraudulent. The fact that some may suspect this is not a demonstration.
The picking of chronologies because they show good correlation with the temperature record is not the same issue. It may, of course, be an issue (particularly if it is done without accounting for that which is demonstrated in Lucia’s OP), but it is not a process of selecting only those proxies which are known in the first place to support a supposedly desired conclusion. Besides which, Mann et al 2008 also presents EIV reconstructions which do not screen for instrumental temperature correlation, so it can hardly be argued that a CPS cherry has been picked to the exclusion of what else is on the tree. The same riposte applies to an objection to “pick two”. If you don’t like the CPS methodology then refer to EIV instead – “0.4°C warmer than the modern
reference period (1961–1990) mean[NH], but still exceeded by the most recent decadal warming.”
I presume that Esper was referring to the picking of sites which were most likely to exhibit a temperature signal (or otherwise a hydrological signal, if that were the subject of the study). Whether or not that can be done reliably is a good question, but suggesting that picking sites with the intention of revealing a good signal is “cherry picking” makes no sense of the phrase “cherry picking”, in my view.
Steven Mosher:
Suspending judgment? Going back to primary sources? Focusing on data? That kind of thing could get you banned on a lot of sites.
With respect to MWP, I have looked at the Idso brothers’ compendium at CO2science.org which is openly partisan but a pretty fair start. I Googled some of the authors, studies and the proxy methods cited to double check and my seat-of-the-pants survey finds (unsurprisingly) that (a) climate proxy science produces rather disparate outcomes (b) more studies than not do indicate a MWP; (c) the notion of the MWP is reasonably well-supported across the entire Northern hemisphere, less so in the South; however, (d) precisely quantifying the temperature is inherently uncertain.
When Mann unveiled Hockey Stick II and SteveM et al had at it, I looked at the graphs someone was kind enough to produce of the various studies that Mann gathered prior to focusing on the ones he liked. I did eyeball testing of several sets at a time and noted that (a) the largest number either had no pattern or did not cover comparable ranges and (b) of those that did, slightly more from Mann’s collection showed a larger rise in the MWP band than the modern era. How he could get a handle and blade out of all that is indeed remarkable.
Until there are support group meetings for people addicted to bristlecone pine and disturbed Finnish lake bottom data (Step 8: “released all data and code…”) we are left with some justifiable suspicion that attacks on the very possibility of the MWP (e.g, “imaginary” forcings) are more ideological than scientific.
mr. steve mosher (#22555)
i’m just an interested observer…a few years ago i thought to research “climate claims” i might read a few books on the basics…one of the books i read was “Climate, History and the Modern Word” by Hubert Lamb…i still keep the book on the small bookcase above my desk for ready reference…since i read it in the 2nd edition, i was struck by differences in the two prefaces (13 years apart)…how things change!!!but one line seemed to resonate with me “…But it is easy to notice the common assumption that Man’s science and modern industry and technology are now so powerful that any change of climate or the enviroment must be due to us. It is good for us to be more alert and responsible in our treatment of the enviroment, but not to have a distorted view of our own importance….”…his chapters on “Roman Times and After” and “Through Viking Times to the High Middle Ages” might be apt for your study…i don’t know if modern scientist recognize his work or find him old fashion but for me it was eye opening…
George Tobin (Comment#22558) October 26th, 2009 at 12:49 pm
Between Steve Mcintyres references to crack and your references here to support group I think there is a hilarious post to do. When I did the Piltdown Mann thing I knew that some would have no sense of humor about it whatsoever, so I will steer clear of doing a similar thing here. hehe. although it would be easy. and I thought of it first.
steven mosher (Comment#22552) October 26th, 2009 at 11:11 am
“You can tell a someones personality just like that? Amazing. Have you ever had these powers tested? I would like to see the results.â€
you just did.
So you don’t have these powers.
There were two problems. One problem was that there is natural forcing. If the natural forcing is too large, CO2 has to be small for current conditions. Thus the IPCC concluded that natural was small
There is your first strawman. It’s a nice piece of fiction, but it’s nothing to do with their thinking.
Natural forcings can be far larger than the current level. There is no compulsion or requirement that they be smaller than CO2. In the early 20th century, according to the IPCC analysis, it was natural forcings that contributed most to climate change. 9.4.1.2
Simon sez:
“I presume that Esper was referring to the picking of sites which were most likely to exhibit a temperature signal (or otherwise a hydrological signal, if that were the subject of the study). Whether or not that can be done reliably is a good question, but suggesting that picking sites with the intention of revealing a good signal is “cherry picking†makes no sense of the phrase “cherry pickingâ€, in my view.”
.
Come now, Simon. How can it be “advantageous” of having the burden of selecting the right sites whilst not knowing exactly what response you’re likely to get? What Esper wrote is completely illogical if he was talking about site selection. Agreed? As you well know, mining for signal is one thing. Mining for noise (i.e. extraneus trend) and attributing that to climate signal is quite another. We’re not talking about the normal brand of cherry-picking here. We’re talking about picking chocolate cherries and calling them regular cherries. Wake up and sniff the chocolate.
Re the MWP being a Northern Hemisphere phenomenon only, did anybody notice the recent Nature paper by Oppo, Rosenthal and Lindley (vol 460, 27 Aug, 2009.) ?
A 2000 year reconstruction of temps from the Indo-Pacific warm pool “suggests that at least during the Medieval Warm Period, and possibly the preceding 1,000 years, Indonesian SSTs were similar to modern SSTs”
http://www.whoi.edu/page.do?pid=7545&tid=282&cid=59106&ct=162
Dave Andrews:
I’m quite certain that Nathan, bugs and Boris were on the cusp of bringing that paper to our attention.
bugs (Comment#22565)
October 26th, 2009 at 4:43 pm
Do tell. Alright Bugs, I tried this with Simon on the previous version of this thread, but he didn’t bite.
I hope this isn’t what you are referring to.
http://img8.imageshack.us/img8/9358/ipcc.jpg
Nathan asked a good question. I think Mosher should consider the last interglacial and mid-Holocene when he starts looking. The problem has been as one goes further backwards in time, confidence intervals increase. Reading Chapter 9 AR4 indicated to me that the problem was that with such large confidence intervals, it was difficult to conclude both very likely and robust. They needed two independent confirmations due to the assumption that most of the post 1950 warming (CO2 is the consideration as stated) was anthropogenic. They state the need for decadal resolution. However, there is the problem of natural variation. With a recognized minimum of 30 years and noted natural variations that occur in the 70 to 80 year frame or longer, the need for about 250 to 500 years or more is needed. It is stated in Chapter 9 of 700 years. Without further research, I cannot say it is an absolute necessity or not. However, it is also clear that Chapter 9 repeated use the millennium for confidence. The mid Holocene and last interglacial are also used as confirmation. The quote “” A substantial fraction of the reconstructed Northern Hemisphere inter-decadal temperature variability of the seven centuries prior to 1950 is very likely attributable to natural external forcing, and it is likely that anthropogenic forcing contributed to the early 20th-century warming evident in these records.”” and its relationship with mid and the last interglacial needs clarification.
The next part “”P679
Past periods offer the potential to provide information not available from the instrumental record, which is affected by anthropogenic as well as natural external forcings and is too short to fully understand climate variability and major climate system feedbacks on inter-decadal and longer time scales. Indirect indicators (‘proxy data’ such as tree ring width and density) must be used to infer climate variations (Chapter 6) prior to the instrumental era (Chapter 3). A complete description of these data and of their uncertainties can be found in Chapter 6…”” would suggest that some research into chapter 6 may resolve some issues.
However, one point against the mid and inter is the statement the instrumental record is too short, and the need of interdecadal clearly indicates the need for tree-ring proxies. The need by the IPCC to “fully understand climate variability and major climate system feedbacks on inter-decadal” time scales does not appear to be a bad assumption. I would say that it is implied by their wording.
Will look at it when I finish getting my kid’s computer fixed, and firewood for the winter.
Mosher or Nathan may beat me.
In keeping with the thread, maybe mid-Holocene, and interglaical were cherry picked. 😉
Bender
“The answer – the connection – is that the alarmist call to action hinges on more than one assertion. First, that current temperatures are already alarmingly high; second, that they will continue to rise higher. The first is dependent upon the magnitude of the MWP. The second is dependent on the climate sensitivity calculation. The magnitude of MWP is not strongly connected to the climate sensitivity calculation*. ”
Yes you answered that at the start, yes, yet as we have discussed AT LENGTH the call to action came well before the Hockey Stick, the Hockey Stick is not a requirement for action. It is only in your head that the Hockey Stick is critical. You saw above that Mosher and Lucia believe we should take some (perhaps not a lot) of action. And your claim about the MWP and it’s relationship to climate sensitivity is at odds with John F Pittman who appeared to be suggesting that the MWP was critical to our understanding.
“second, that they will continue to rise higher.”
That is the critical point of the call to action on Global Warming. This point has nothing to do with the MWP, and it doesn’t particularly matter what the MWP was like, this second point remains. And it remains because that’s what our understanding of paleoclimates tells us and what our understanding of radiative physics tells us.
John F Pittman
Thanks for the pleasant discussion.
I would think that the best you can get is a rough estimate for all the relevant values. The clarity from proxies and direct evidence will never be enough to satisfy the engineer in you (and all the other engines around here). However, temperatures rising only to the levels they were at the peak of the last interglacial will be bad. Sea level peaked around 6m higher than present day – that’s bad.
October 26th, 2009 at 4:43 pm
In the early 20th century, according to the IPCC analysis, it was natural forcings that contributed most to climate change.
Do tell. Alright Bugs, I tried this with Simon on the previous version of this thread, but he didn’t bite.
I hope this isn’t what you are referring to.
No, course not. Why would I refer to that. What madness could have seized me. That, hahahahaha, no no no no no no no no no. Of course not THAT!.
Why do you ask?
bugs (Comment#22578)
October 26th, 2009 at 7:43 pm
Just the usual.
I have always hated the rather vapid phrase “call to action” when deployed in the AGW context. It seems to mean giving a blank check to unaccountable planners with all of the economic and political injury inherent in such grants of power.
Oddly enough, it it not a “call to action” to act to curtail environmentalist litigation from strangling the domestic nuclear energy industry. In the same vein, The Late Lion of Limosine Liberals did not hear a call to action to deploy wind energy turbines within sight of expensive New England real estate– but I digress…
The fact is, a blank-check “call to action” for something as pointless and politician-serving as cap and trade or as destructive as draconian carbon taxes DOES require a hockey stick, DOES require an Oscar-winning silly polemic, DOES require a quasi-religious alarmist orthodoxy and DOES require a denial of the MWP and anything else that might lead to doubt or heresy.
Many of the people who comment here are “lukewarmists” who clearly have no ideological, personal or scientific objection to rapid development and implementation of new energy technologies.
But being stampeded into bad choices implemented by politicians with bugs’ grasp of science and/or Nathan’s adherence to the party line by means of questionable methods and bad science is not a “call to action” that most of us are prepared to accept.
For Nathan to suggest there is a world of difference between myself and Pittman’s read of IPCC means Nathan must have tracked down my asterisked “intrinsic variability” argument at CA (along the lines of Raven’s), and found some major differences. I’d like to see those differences listed. I’d be surprised if anything were to materialize.
.
Action scaled to evidence: this is rational.
The thing is, imo the proposed action at the moment is no way near being scaled to evidence. From my perspective, the rational thing is to take much greater action much sooner.
Nathan:
Michael Mann has built his career on the hockey stick.
Let’s see you deny that.
Seriously, you’re the only one here who believes this BS (namely that only “deniers” or “luke warmers” make a big deal of the hockey stick) and most of us have long ago gotten bored with your spamming of this same nonsense tiresomely over and over…
Nathan,
“Yes you answered that at the start, yes, yet as we have discussed AT LENGTH the call to action came well before the Hockey Stick, the Hockey Stick is not a requirement for action.”
Yes, and there was NO hard evidence when this CALL TO ACTION was first trumpeted from the ramparts.
Hansen’s fellow academics were still working on Global Cooling when he started resurrecting a triply disproven 100 year old theory. In 1988 he had his 100 year old retread and 10 years of data that proved WHAT?????
Your claim that the MWP existence didn’t matter is contradicted by the FACT that the IPCC jumped on Mann’s fra, uhhhh, sloppy work like a CRACK addict on free crack. Even after the Wegman report and the NAS report y’all STILL can’t let go of this scientific ABORTION!!!!! So called Paleo Scientists are STILL TRYING TO MAKE TEMP HOCKEY STICKS!!!
Admit that all of Mann’s hockey sticks are poor science and that, so far, it would appear that Briffa’s and other work associated with Mann’s are also poor.
After that admission, THEN we can start discussing whether there is enough evidence to support a CALL TO ACTION without them!!!!! Until you can admit the poor work and doubtful results, your implied claim that it doesn’t matter is FALSE!!!
Now, since your exact statement is that it isn’t a REQUIREMENT, we could say that the statement isn’t completely false, just misleading.
We will all be waiting with baited breath your admission that the Hockey Sticks are CRAP!!!
David Gould,
“From my perspective, the rational thing is to take much greater action much sooner.”
Then you would support nuking Iran, Russia, China, Cuba, Venezuela, North Korea… NOW???
kuhnkat,
Yes, that is exactly what I said I supported. Whenever I say, ‘much greater action’ I mean launching nuclear strikes at lots of different nations this instant. And I demand massive nuclear strikes, not puny ones. Now.
David, that is an extremely effective plan. At least if we believe Carl Sagan’s calculations, we can expect an immediate and extended cooling of the Earth.
The polar bears will be pleased.
And polar bears will be much more easily able to find mates in the long night of the arctic winter, as they will all glow in the dark.
It’s a win win.
Michael Mann has built his career on the hockey stick.
From reason, there are people who want you to think that Mann and Hansen are the IPCC. They aren’t. Mann hasn’t ‘built his career’ on the hockey stick, all scientists have to specialise, that’s part of his. If Mann hadn’t done it, someone else would have.
bugs:
Who would that be? Nobody here.
Pfft.
My BS meter just broke. I think it’s beyond repair.
David:
On the downside there may be fewer Inuits for them to munch on, which will increase the predation on arctic seals.
I think it is fair to say the arctic seals will not be pleased.
Kuhnkat
“Yes, and there was NO hard evidence when this CALL TO ACTION was first trumpeted from the ramparts.”
What? This is simply wrong. You mean to say that between 1976 and 1998 there was a call to act on Global Warming, with zero evidence. That’s just dumb.
“Your claim that the MWP existence didn’t matter is contradicted by the FACT that the IPCC jumped on Mann’s fra, uhhhh, sloppy work like a CRACK addict on free crack. Even after the Wegman report and the NAS report y’all STILL can’t let go of this scientific ABORTION!!!!! So called Paleo Scientists are STILL TRYING TO MAKE TEMP HOCKEY STICKS!!!”
You are going a bit berserk here Kuhnkat… Ummm well… You seem to be slightly unhinged. I think the obsession with hockey Sticks over at CA is fueling this belief that they are the vital piece of info – especially with regards to the MWP.
George Tobin
“I have always hated the rather vapid phrase “call to action†when deployed in the AGW context. It seems to mean giving a blank check to unaccountable planners with all of the economic and political injury inherent in such grants of power.”
Well, if that’s your interpretation then there’s not much we can do about it. It sounds like hysterics to me, and quite a bit of hyperbole.
Carrick
“Michael Mann has built his career on the hockey stick.”
I don’t know if that’s true or not. but in the end, so what? Let’s assume his career has been built on that – or rather that he has continued to research similar topics. Big deal. Has he somehow made a fortune out of it?
My BS meter just broke. I think it’s beyond repair
So no one is allowed to specialise in research into past climate, if they do you will dissaprove because it is their specialisation.
bugs:
Make a note to order more straw for all of those straw men you keep building.
Or more to the point, find somebody for whom this opinion fits. Nobody here as far as I can see.
Nathan:
Well you keep making a big deal about the only people who care being people on this blog (or CA).
Clearly even you don’t believe that, as you have now demonstrated
Amongst your many qualities are the inability to comprehend other people’s writings, the willingness to rail against them based on your own miscomprehension’s, and even your own willingness to disown statements of “fact” that you just so recently made.
Such as:
You are a tiresome fool, and little more.
Bender
You want me to randomly search CA for what you had to say about Ravens comment on intrinsic natural variability? Give me a break.
Here is what you said:
“The magnitude of MWP is not strongly connected to the climate sensitivity calculation*. ”
John F Pittman
“For those who think the MWP is non-essential to IPCC AR4, you are incorrect. This can be determined in Chapter 9.”
If you have a link to what you claimed at CA at some post at some time in the past, give it.
Kuhnkat
“Admit that all of Mann’s hockey sticks are poor science and that, so far, it would appear that Briffa’s and other work associated with Mann’s are also poor.
After that admission, THEN we can start discussing whether there is enough evidence to support a CALL TO ACTION without them!!!!! Until you can admit the poor work and doubtful results, your implied claim that it doesn’t matter is FALSE!!!
Now, since your exact statement is that it isn’t a REQUIREMENT, we could say that the statement isn’t completely false, just misleading.
We will all be waiting with baited breath your admission that the Hockey Sticks are CRAP!!!”
well I can’t “admit” they are crap, because I don’t know. I can’t say if the MWP was warmer, as warm, or cooler than now, because I don’t know.
I understand that because of increasing CO2 we can expect the climate to warm at least as warm as it was during the Holocene Optimum, and most likely warmer than the previous interglacial. For these reasons alone, it would be wise to limit CO2 emissions.
Carrick
what a load of nonsense.
You asked in Mann had made his career out of the Hockey Stick…
I said “I don’t know”
It has nothing to do with whether the Hockey Stick is essential to the case for AGW.
Nathan:
I didn’t “ask”. I asserted that.
And it was in response to a comment of yours “It is only in your head that the Hockey Stick is critical”, one that was clearly false.
Oh I see Carrick. You think that the RealClimate post proves that the HockeyStick is critical to the case for AGW, not that Michael Mann has made his career out of it.
I don’t think that the Real Climate post proves that. You have it the wrong way round. That is, they had some climate senstivity extimates (from elsewhere – I believe in the IPCC they say they actually used the Holocene optimum and Last interglacial peak) and the Hockey Stick gives support to those estimates, so they “agree well, in large part, with the empirical, proxy-based reconstructions.” If those reconstructions are found to be faulty (ie we can’t really know what happened), it doesn’t make the case for AGW go away.
Nathan:
What is special and “optimal” about pre-industrial levels of CO2? Why are those optimal, and not, say the 800 ppm value that was more typical prior to the latest round of ice ages?
The MWP does raise an important issue though, because if natural climatic variability is large enough, then you really have to jack up AGW before that outweighs natural variability.
Because as long as our climate is dominated by natural variability, the desire to control our environment through controlling CO2 levels remains chimeric at best.
bender (Comment#22581) October 26th, 2009 at 9:27 pm
Action scaled to evidence: this is rational.
Ya, move malibu residents inland, restore the coast.
Nathan:
This is yet another strawman. Do you AGW true believer types know how to argue a point without employing them?
Of course, my point wasn’t whether the MWP is important or not, but rather whether you were correct in your characterization ” is only in your head that the Hockey Stick is critical.”
Obviously it is important in other people’s heads, and maybe their wallets too.
Bugs
http://www.youtube.com/watch?v=p7w64fbqYQY&feature=related
Carrick
That’s a really stupid point.
On to more sensible points
“Why are those optimal, and not, say the 800 ppm value that was more typical prior to the latest round of ice ages?”
Obviously it is better to keep CO2 to levels below that so we don’t have to deal with a 6m sea level rise. That won’t be fun.
Are you seriously thinking that the climates of the Miocene or earlier would be really great? With little or no icecaps?
Also, as a side issue, if the levl of CO2 is around 800 ppm it will be like living in a ‘stuffy office’ you know that sort of sleepy feeling you get – won’t be pleasant at all. Better to breathe fresh air.
http://www.ias.ac.in/currsci/jun252006/1607.pdf
So there are plenty of reasons to limit the CO2 levels.
Mosher
“Action scaled to evidence: this is rational.”
yes, but what does it mean? It’s a motherhood statement that goes nowhere.
The evidence is that CO2 levels that are high leads to no ice caps. This means higher sea levels. And you just want to move everyone? Surely that would cost far more than simply making sure the CO2 levels don’t get too high.
Make a note to order more straw for all of those straw men you keep building.
Or more to the point, find somebody for whom this opinion fits. Nobody here as far as I can see.
You made a disparaging remark about Mann. So far I can’t find what the problem is that you have with him.
steven mosher (Comment#22605) October 27th, 2009 at 12:02 am
Bugs
I’m just trying to see what evidence you have for your ‘sly’ detection powers, beyond your own self-estimation. So far, nothing. Perhaps you can’t really detect it after all, and the scientists you are maligning are not ‘sly’ at all.
Nathan says:
“Give me a break ”
.
Umm, no. I don’t believe you’ve earned one.
The goofballs are driving reason off this thread. It’s a shame. It was a good thread. Cherry-picking is a real problem.
Nathan,
“The evidence is that CO2 levels that are high leads to no ice caps. ”
Not necessarily since at least some of the proxies for CO2 and temp suggest that the earth was cold during periods of high CO2.
http://i224.photobucket.com/albums/dd137/gorebot/Geological_Timescale_op_927x695.jpg
Before AGW the theory felt that continental drift was the largest factor in determining the presence of ice caps.
“The goofballs are driving reason off this thread”
It’s the nature of activist leftists to bully their way into controlling stuff. (Or at least think they are in charge) It’s just the way they are. So they “took over” this thread. They can start taxing us while they are at it, and they can start tell us what toliet paper to use and what not to have for breakfast. We’ll get right to it, sirs. 😉
Andrew
It’s the nature of activist leftists to bully their way into controlling stuff. (Or at least think they are in charge) It’s just the way they are. So they “took over†this thread. They can start taxing us while they are at it, and they can start tell us what toliet paper to use and what not to have for breakfast.
People make claims, then it turns out they don’t have any evidence. That’s not my fault. And it wasn’t me who brought up people being ‘sly’.
bugs,
“People make claims, then it turns out they don’t have any evidence.”
You mean like AGW leftist scaremongers?
Everyone has an opinion. Other’s opinions may differ from yours. It’s OK, just don’t make the mistake of thinking your opinion is akin to a Decree From On High.
Andrew.
You mean like AGW leftist scaremongers?
Everyone has an opinion. Other’s opinions may differ from yours. It’s OK, just don’t make the mistake of thinking your opinion is akin to a Decree From On High.
No, I asked for evidence that he can tell when someone is being ‘sly’. No opinion there.
“No, I asked for evidence that he can tell when someone is being ’sly’. No opinion there.”
No but it’s his opinion that someone is being sly. It’s your opinion that there’s no evidence of that.
Who cares?
Andrew
No but it’s his opinion that someone is being sly. It’s your opinion that there’s no evidence of that.
Who cares?
No, it’s fact he has offered no evidence.
bugs,
“…he has offered no evidence.”
*HE DOESN’T HAVE TO*
Andrew
bugs makes me ill
Nathan:
What you said was stupid, I agree. You should quit trying to claim things that aren’t true.
Nathan said “”Thanks for the pleasant discussion.
I would think that the best you can get is a rough estimate for all the relevant values. The clarity from proxies and direct evidence will never be enough to satisfy the engineer in you (and all the other engines around here). However, temperatures rising only to the levels they were at the peak of the last interglacial will be bad. Sea level peaked around 6m higher than present day – that’s bad.””
Thanks. I do think it a shame that persons are starting a food fight. I think unnecessarily.
The problem with “rough” means lack of definition. You are correct about satisfying engineers. However, allow me to give some prospective to this. The IPCC use GCM’s and the paleo, among other considerations to assign climate sensitivity. One need not worry so much about 6M sea level if the odds are low. Whether the odds are high or low depend on climate sensitivity and the nature of feedback. If CS is high and water vapor is negative, it is the same as CS real low and wv only moderate. The 6M is very low probability and would be on the order of about 3000 years, more or less depending on assumptions based on what Hansen stated.
The problem is “rough” The GCM’s are initial value and time (path) dependent step wise constructions. If the initial values are too rough and/or CS too rough, they tend to explode. IIRC, GISS model E already has to use a non-physical hyperviscous layer to keep from blowing up. Dr Browing has a math peer reveiwed publication showing ill-posed, intractable solutions, and Dr Sulie Gavel (sp?) has model runs that are claimed to confirm this. Even if they could keep the models from blowing up, Santer et al already demonstrate the “not inconsistent with models” for a flat trend when it was to be 2C/century. With rough the CI would be so big another failure occurs. If you look, the IPCC in chapter 10 throw out the concept of natural noise or variability, and claim although they don’t do weather, they do climate using a Bayesian mean climate criteria. If the CS is too rough, even the mean cliamte scenario is so large that inaction would be a credible position for governments to take. THe IPCC had a need for a better defined input, and it is in Chapter 9 that tree-ring proxies were what gave them the decadal. In order for the decadal at 2100 to make sense (not have hell or snowball earth) too rough would not be useful. I think you neeed to consider the problem with autocorrelated has on CI’s. Because in a very real way, GCM’s are the ultimate autocorrelated series.
John,
The IPCC’s AR$, Chapter 9, references two studies which sought to estimate CS over the period including the MWP, primarily Hergel et al 2007 and also Andronova et al 2004 (only these two – there are many more considered against the temperature record, and particular weight is also given to LGM estimates). They comment on Hergel thus:
“All reconstructions combined yield a median climate sensitivity of 3.4°C and a 5 to 95% range of 1.2°C to 8.6°C (Figure 9.20). Reconstructions with a higher amplitude of past climate variations (e.g., Esper et al., 2002; Hegerl et al., 2007) are found to support higher ECS estimates than reconstructions with lower amplitude (e.g., Mann and Jones, 2003).” [my bold].
In other words, and regardless of arguments that they should be assessing climate in any other way, if they had assumed a stronger amplitude MWP than in any of the reconstructions assessed then the estimate of CS would have been argued higher.
The Hegerl paper is available here:
http://www.geos.ed.ac.uk/homes/ghegerl/Hegerl_et_al_sensitivity.pdf
It will be noted that the implication of their study was to constrain the upper end of CS estimates!.
Simon Evans:
The Hergerl et al paper you cite is pretty weak and was the subject of lots of discussion when it came out. Not even Gavin Schmidt defended the huge sensitivity ranges they ginned up.
When asked to disclose what they actually used for their data series, they stonewalled (naturally) but SteveM “reverse-engineered” it and is pretty sure it is nothing more than a rather small set of warmed-over mostly Briffa reconstructions.
Also see this for another example of the criticisms.
Hergerl is one of the IPCC insiders. Given the clubby politicization of that group it is always best to get some confirmation outside of The Team before citing their findings as gospel. Links to official statements from orthodoxy-approved authors is fine for impressing ‘bugs’, but most of the folks who comment here have rather higher standards.
George,
The Hergerl et al paper you cite is pretty weak…
I’m afraid you entirely miss my point. It’s of no consequence to me whether or not the Hergel paper is strong, weak or just utter hogwash. I am simply pointing out that this was the IPCC’s primary reference for CS estimates relating to the MWP period, and thus insofar as the IPCC’s notion of CS depends upon MWP reconstructions (and I think not very far at all – indeed the Hergel paper is mostly focused on later periods anyway), which I understand is the case John is putting, then I conclude that a stronger MWP would imply a stronger CS. Alternatively, we may conclude nothing whatsoever from it, if you prefer – that suits me too! I am not arguing that there was a strong global MWP, and that thus our estimate of CS should be higher. I think we just don’t know well enough. However, if there was such a thing, then the IPCC’s estimate of CS would be argued higher (regardless, as I’ve said, of whether or not you or others think they are assessing climate in the right way).
Nathan (Comment#22607) October 27th, 2009 at 1:30 am
Mosher
“Action scaled to evidence: this is rational.â€
yes, but what does it mean? It’s a motherhood statement that goes nowhere.
The evidence is that CO2 levels that are high leads to no ice caps. This means higher sea levels. And you just want to move everyone? Surely that would cost far more than simply making sure the CO2 levels don’t get too high.”
Actually not. Somewhere around the web when I first started looking at this a couple years back I found an EPA study on the issue that put the cost for the US as something quite reasonable. In any case reformed building regulations put the cost where it belongs. That always works best. But lets stick to this case which is illustrative of the issue.
Malibu California ( just for example) is built almost in the tide zone. Having spent some time there I can tell you that it suffers from storm surge damage in some years and horrible fires in other years. The people who live there make millions. (Bender cleans their pools and also makes millions ) their property is in danger if sea level rises. What is the best solution? To tax everyone including future generations so that these people can maintain this lavish lifestyle, living in storm surge.. or should you employ other means? ( like forced insurances, no rebuilding, retreat over time )
bugs,
“…he has offered no evidence.â€
*HE DOESN’T HAVE TO*
Andrew
Then he withdraw the ‘sly’ accusation.
“bugs,
“…he has offered no evidence.â€
*HE DOESN’T HAVE TO*
Andrew
Then he withdraw the ’sly’ accusation.”
bugs,
You are demanding that a blog commenter withdraw an accusation of ‘sly’? This is what you spend your time thinking about?
And you wonder why people can’t take you seriously?
Andrew
Simon Evans:
The point regarding an inference of a higher CS from that reconstruction and others like it is what is crap. That is *not* a given. To try to spin questionable science into a heads-I-win-tails-you-lose scenario is silly.
The whole point of the MWP controversy is that deliberate attempts to minimize it combined with Frankensteinian grafts of Instrumental data onto such reconstructions invariably overstate CS, serve to justify extreme alarmism and promote bad policies (“calls to action”).
Your approach exemplifies what is wrong with so much climate science–the answers to fundamental questions (e.g. sensitivity) are largely assumed. As a result, this stuff often reads more like opinions from hired expert witnesses rather than the work of independent scientists.
Simon you said “”I am simply pointing out that this was the IPCC’s primary reference for CS estimates relating to the MWP period, and thus insofar as the IPCC’s notion of CS depends upon MWP reconstructions (and I think not very far at all – indeed the Hergel paper is mostly focused on later periods anyway), which I understand is the case John is putting, then I conclude that a stronger MWP would imply a stronger CS.”” I am saying that CS is one aspect. However, remember that in chapter 9, the basis is not just CS.
The IPCC say “An alternative approach, which has been pursued in most work reported here, is based on varying parameters in climate models that influence the ECS in those models, and then attaching probabilities to the different ECS values based on the realism of the corresponding climate change simulations. This ameliorates the problem of feedbacks being dependent on the climatic state, but depends on the assumption that feedbacks are realistically represented in models and that uncertainties in all parameters relevant for feedbacks are varied. Despite uncertainties, results from simulations of climates of the past and recent climate change (Sections 9.3 to 9.5) increase confidence in this assumption.””
The important parts are attaching probabilities, realistically representing feedbacks, etc. If MWP was much warmer, it would mean that “”uncertainties in all parameters relevant for feedbacks are varied”” would be UNTRUE. Remember Chapter 9 has the famous (infamous) statements 1) “”This conclusion takes into account observational and forcing uncertainty, and the possibility that the response to solar forcing could be underestimated by climate models. It is also robust to the use of different climate models, different methods for estimating the responses to external forcing and variations in the analysis technique.”” and 2) “” No climate model that has used natural forcing only has reproduced the observed global mean warming trend or the continental mean warming trends in all individual continents (except Antarctica) over the second half of the 20th century.””
However, it should be naively apparent that if the MWP was much warmer than CWP, models would have to be able to do the MWP since it is necessary for the IPCC to have “the assumption that feedbacks are realistically represented in models and that uncertainties in all parameters relevant for feedbacks are varied.”” One cannot claim realistic (feedback) and that uncertainties in ALL parameters relevant to feedback has been done if the MWP is warmer than the CWP, and further claim “” No climate model that has used natural forcing only has reproduced the observed global mean warming trend or the continental mean warming trends in all individual continents (except Antarctica) over the second half of the 20th century.”” This would be conflicted fatally, such that one would claim a wamer MWP FALSIFIES the claims in Chapter 9. Please pay close attention to realistic and all.
mosher says:
“yes, but what does it mean? It’s a motherhood statement that goes nowhere.”
Exactly my point. Action without direction is spinning your wheels in circles.
I want to thank Simon Evans for pointing to the IPCC statement and John F Pittman for parsing the proposition (what would a warmer MWP mean) according to IPCC’s own reasoning. I look forward to continuing dialogue along those lines. They are obviously reading the document more closely than I have. I do not accept (for various reasons) IPCC’s reasoning as bullet-proof and it seems Pittman might concur. This could very well account for why I seem to have a different frview from Pittman’s read of the IPCC. (Nathan interpreted this to imply that Pittman and I are at odds. This is not the case. So far as I have seen, we are on the same page. When I say CS calculation is “not strongly tied” to MWP I mean to say that it is only weakly tied to the MWP, because it is more strongly tied to (i.e. constranied by) other parameters. I may be wrong, but I am not in disagreement with Pittman’s read.)
.
Where I seem to be in disagreement is with the IPCC quote that Simon Evans pulled out. Thanks, Simon. This makes no sense to me, so I’m very surprised I missed it. I will have to read it over for context, and to see the logic and data behind of the argument. But the citing of Mann in support of that statement is, well, noteworthy, to say the least.
.
Again, I look forward to continued discussion by informed voices such as Evans and Pittman. More light. Less heat.
John F Pittman (I will call you JFP):
Browning’s lead co-author was Sylvie Gravel.
JFP says:
“if the MWP was much warmer than CWP, models would have to be able to do the MWP since it is necessary for the IPCC to have “the assumption that feedbacks are realistically represented in models and that uncertainties in all parameters relevant for feedbacks are varied.— One cannot claim realistic (feedback) and that uncertainties in ALL parameters relevant to feedback has been done if the MWP is warmer than the CWP, and further claim ҠNo climate model that has used natural forcing only has reproduced the observed global mean warming trend or the continental mean warming trends in all individual continents (except Antarctica) over the second half of the 20th century.— This would be conflicted fatally”
.
And that is “my argument at CA”, in a nutshell. (Or, rather, that would be the argument I would have advanced in a single concise paragraph if I’d been as well-versed in IPCC jargon.) Same thing. It’s what I equally (but ambiguously) referred to as “Raven’s line of argument”. It’s Robock. It’s Tsonis. What is this thing called “internal variability”? How do you account for it in statistical attribution exercises when you don’t know it’s true nature? Why are the models so universally BAD at simulating it? Why do they produce ITCZ but no THC? No ENSO? Etc.
.
If internal variability is “higher than calculated” then external forcings must be “lower than calculated”. Proclamations to the contrary must be invoking either voodoo math or voodoo semantics.
George Tobin (Comment#22630)
George,
I think your post is quite rhetorical, and I can’t see that it makes sense. If you would like to demonstrate how a stronger MWP would have led to a reduced assessment of CS then please go ahead.
John F. Pittman (Comment#22631)
John,
I’m kinda wondering whether this thread has run its course, but I hate not responding ;-).
However, it should be naively apparent that if the MWP was much warmer than CWP, models would have to be able to do the MWP
Well, I don’t know what you mean by “much warmer” in the first place. You previously (rather bizarrely, imv) claimed that pre-1998 the MWP was thought to be equivalent to the Holocene Optimum. I quoted Lamb against that view and asked what your view was based upon, but you haven’t told me.
But let’s presume you mean that, regardless of justification. Then yes, if that were shown to be so, then CS would have to account for it. And yes, that means that forcings have been underestimated in their effect (including CO2, of course), and we would have to refigure our assessment of the temperature record period (and yes, it would mean that the IPCC would have more work to do). What it would not mean is that CO2 would thus be diminished as a forcing. Until such time as we have convincing evidence of your interesting claim of the MWP being equivalent to the Holocene Optimum I rather think this is a speculative and not very informative discussion.
Simon,
Can you choose something middle-ground, say, for MWP and reason from that? e.g. Suppose MWP is half-way between HTO and CWP (current). (I want to avoid the painting of strawmen as much as possible.)
.
I will have a discussion point for lucia, later, on the false dichotomy (?) of global/local.
Simon Evans (Comment#22624) October 27th, 2009 at 11:51 am:
John, The IPCC’s AR$…
Heh 🙂
Thanks Bender. I was not where I could easily search. My spelling is terrible. If Sylvie Gravel reads this, I hope my apology will be accepted.
Simon, I thought I was clear. My wife tells me I always think that, but it is untrue. I have seen over many years, about 46 of them at this point, many different estimates of the Holocene Optimum and the MWP. I did not pay much attention to the sources then, and definetly couldn’t do them justice at this point. I used them only as an example of possibilities which a thread about chery picking should not be a far stretch. A fair logical construct since none of us were there to measure it. The statement I wanted you to take is that IF and I mean IF, the MWP was warmer than the CWP, it causes problems for the IPCC as I argued above. The much warmer MWP was a logical construct to hopefully enable readers to see the point I was making. Especially since in this thread we spent so much time discussing how the possible cherry picking could have seriuosly underestimated the MWP. Perhaps not since it is a cherry pick.
Your statement “” What it would not mean is that CO2 would thus be diminished as a forcing.”” This is not what the IPCC said they were doing. They have to define both the feedbacks, and the forcings, and it has to mean that no natural forcings (will have to include feedbacks per the IPCC’s description) can explain the warming for the second half of the 20th century. I did not say that it would diminish as a forcing, in and of itself, I offered the construct of negative water feedback in a previuos post.
I think the disagreement arises from that the IPCC stated realistic and all relevant forcings were considered. You say “”And yes, that means that forcings have been underestimated in their effect (including CO2, of course), and we would have to refigure our assessment of the temperature record period.”” But this would mean that they had not done all relevant forcings with realistic probablities, and yes, until corrected it would mean falsified, not as you say, (and yes, it would mean that the IPCC would have more work to do).
bender,
I’ll divert slightly before being more direct –
The thing is, to me, that Mann et al 2008 states, of EIV reconstructions, that:
>Peak multidecadal warmth centered at A.D. 960 (representing
average conditions over A.D. 940–980) in this case corresponds
approximately to 1980 levels (representing average conditions over 1960–2000).
and of SH reconstructions that:
the estimated uncertainties are compatible with the possibility that recent SH warmth might have been breached during brief periods in the past.
So I’m not uncomfortable with the rough idea that MWP temperatures might have roughly been close to, a bit below or a bit above, current. That ‘roughly’ word’ gives a fair indication of my view of proxy evidence, btw.
I think models are more than likely to be a bit ‘rough’ too. It’s perfectly plausible that we are at a natural mini-optimum, accounted for significantly by natural variation. However, at just that point we happen to be adding a positive forcing to the equation, I think. My concern is not so much with today’s temperatures as with tomorrow’s.
So, to be more direct, you wonder about how I’d reason in response to the MWP being demonstrated to be “half-way between HTO and CWP (current) “. Firstly I’d get over my surprise ;-), then I’d want to know what we agreed the holocene optimum to be likely to be in relation to current. Indications seem to suggest 1C – 2C warmer than present, globally (I’d probably favour the 1C globally, but let’s not be too particular with uncertainty!). That was 9 to 5 thousand years ago, of course, when we weren’t worrying about economies;-).
I guess some would argue a higher figure, I don’t know. None of us knows enough, really.
I think GHGs are forcings. I think that human societies have pushed the envelope of sustainability, so that they will be very vulnerable to change, whether naturally induced or otherwise. I don’t think the USA, or the UK (where I am) are geopolitical islands, so I don’t think that ‘impact’ can simply be determined in terms of local climate effect. I don’t think that the way our global society is now would have survived well the conditions of such a Holocene optimum, so I don’t think we should contribute towards re-hitting it!
John F. Pittman (Comment#22640)
John,
I’m not sure how we’re in disagreement, really. I agree that if a global MWP were shown to be significantly warmer than present then it would have to be refigured and, indeed, some current IPCC statements would be rubbished. So let that be shown, if it was so!
Your statement “†What it would not mean is that CO2 would thus be diminished as a forcing.— This is not what the IPCC said they were doing. They have to define both the feedbacks, and the forcings, and it has to mean that no natural forcings (will have to include feedbacks per the IPCC’s description) can explain the warming for the second half of the 20th century. I did not say that it would diminish as a forcing, in and of itself, I offered the construct of negative water feedback in a previuos post.
The research doesn’t “has to mean” anything. Just as others casuallyu throw around ‘sly’, you also attribute motivations to people with no evidence. They are doing research, the research is ongoing, science is usual. They don’t know everything, and they never will. Science as usual.
Between 10,000 BC and 1700 AD, CO2 hardly changed at all. So the IPCC will have to get rid of all the warm periods since the last Ice Age ended.
Then they will have to get rid the Eemian Interglacial 120,000 years ago which was about 2.0C warmer than today – again CO2 unchanged at about 275 ppm.
Then they would have to explain the Miocene when temps were anywhere from 2.0C to 3.5C warmer than today – yep, you guessed it CO2 at 250 ppm.
etc. etc.
Steven Mosher
‘To tax everyone including future generations so that these people can maintain this lavish lifestyle, living in storm surge.. or should you employ other means? ( like forced insurances, no rebuilding, retreat over time )”
Well, I am not sure how you come to this conclusion. The recent rise in CO2 levels was not caused by people living on the coast, so why should they be expected to carry the burden. CO2 emissions are currently an external cost, they need to be internalised – the only way that happens is if you tax the emmitters, and they then pass the tax on.
John F Pittman
“If MWP was much warmer…”
Yes I guess if there was a massive difference between now and the MWP it would make things rather confusing. But this is a poor argument as most people who think the MWP was global don’t put it much (if at all) warmer than today.
There’s no evidence of a “much warmer MWP”.
Bill Illis
“Between 10,000 BC and 1700 AD, CO2 hardly changed at all. So the IPCC will have to get rid of all the warm periods since the last Ice Age ended.
Then they will have to get rid the Eemian Interglacial 120,000 years ago which was about 2.0C warmer than today – again CO2 unchanged at about 275 ppm.
Then they would have to explain the Miocene when temps were anywhere from 2.0C to 3.5C warmer than today – yep, you guessed it CO2 at 250 ppm.”
This is the point I was trying to make earlier, that is that there are plenty of other global events that seem to be nicely accounted for by modelling. If the MWP was much warmer than the CWP it is very difficult to explain the other warm periods (which are largely accounted for by either insolation changes – last interglacial and Holocene Optimum, or by changes in ocean currents and progressive glaciation – Miocene climate)
Nathan and Simon Evans: where the diagreement resides.
I used the much warmer MWP as a logical construct to show why it is important. This is not the same as saying that it has to be much warmer than CWP. Once one understands that the IPCC use it to explain the last half of the 20th century and determine the amount of temperature difference this implies, then a MWP close but not as warm as the CWP would cause falsification of IPCC’s position. The question is how much is required. Part of the answer lies in how the LIA is done. This is why in previuos posts I talked about this. If the MWP is a little higher and the LIA a little cooler, then the same reasoning will apply. Remember this is the point of that mean climate condition they use. It also requires realistic and all feedback parameters considered. As I stated earlier (may have been at JeffID’s blog, though), as this range expands, the not inconsistant with the models drives the range from iceball to freewater winter Arctic, but this violates their Bayesian a priori of “weather noise” versus climate signal for very likely and robust. So with a warm MWP either the IPCC is falsified by unrealistic and not all feedback parameters considered, or the Bayesian support for projecting fails ie can’t tell weather from climate.
Thank you, JFP & Simon. I think we have shown that there is more agreement than disagreement, as far as the wide spectrum of (ill-informed?) opinion goes. The magnitude of MWP “matters” for a couple of reasons.
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Simon, I also do not like the idea of gambling on feedbacks when the convective dynamics are uncertain. I’m ok with a “precautionary principle”, but, as always, the question is: what exactly are we up against? This requires that the science be undistorted by politics. “Trust us, we’re the experts” is an antiquated attitude that I just do not share.
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To get back to the OP: cherry-picking that irons out the MWP – whether by accident or by intent – would be a problem.
JFP says:
“As I stated earlier (may have been at JeffID’s blog, though), as this range expands, the not inconsistant with the models drives the range from iceball to freewater winter Arctic, but this violates their Bayesian a priori of “weather noise†versus climate signal for very likely and robust.”
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JFP: here is why I am intrigued by Broecker (2001) and his far-reaching (but not global) 1500-year THC cycle (supposedly responsible for MWP-LIA cycling). First, as I said before, the GCMs do not come close to simulating this kind of high-order AR behavior. lucia has shown that in spades. Second, what is the possibility that the world’s oceans – and recall this is an area of active research by *very* smart people like Tsonis & Swanson – behave in part as a slow-motion Belousov-Zhabotinsky thermochemical oscillator? I leave this question “as is” and hope it piques lucia’s interest. (Or Tsonis & Swanson’s, for that matter.)
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Bonus assignment: Do we *really* understand the causal mechanics of the D-O oscillation?
Bill Illis (Comment#22643) October 27th, 2009 at 6:37 pm
Between 10,000 BC and 1700 AD, CO2 hardly changed at all. So the IPCC will have to get rid of all the warm periods since the last Ice Age ended.
Then they will have to get rid the Eemian Interglacial 120,000 years ago which was about 2.0C warmer than today – again CO2 unchanged at about 275 ppm.
Then they would have to explain the Miocene when temps were anywhere from 2.0C to 3.5C warmer than today – yep, you guessed it CO2 at 250 ppm.
Complete tripe. CO2 is not the only forcing on the climate, and it has never been claimed that it is.
Nathan,
“What? This is simply wrong. You mean to say that between 1976 and 1998 there was a call to act on Global Warming, with zero evidence.”
STRAWMAN ALERT!!!
I WROTE 1988 not 1998.
I wrote ZERO HARD EVIDENCE.
this is your delusion as it is easily rebutted. Try addressing what I WROTE.
David Gould,
Well, maybe you should be a little more explicit when you say much greater action much sooner. Leaving it so open obviously leaves a lot of area for interpretation.
How about, you would believe in starting to build spaceships immediately to evacuate the earth due to the 100% certainty that it will become unhabitable some day.
Don’t like that one either??
Maybe you should explain how your statement, and the underlying theory SHOULD be interpreted so STUPID activities aren’t undertaken with poor evidence!!!
Nathan dithers,
“well I can’t “admit†they are crap, because I don’t know. I can’t say if the MWP was warmer, as warm, or cooler than now, because I don’t know.”
Well Nathan, since you DON’T KNOW, and apparently do not know enough to make an educated guess, my educated GUESS is that we can all IGNORE anything you have to say on the subject of Reconstructions!!!
Since you also DON’T KNOW whether the MWP was hot, cold, average or whatever, my educated GUESS is that we can IGNORE anything you have to say on the MWP also.
Since you have no idea of the MWP, my educated GUESS is that we can IGNORE anything you have to say on the current and changing atmospheric sensitivity!!!
Thanks for saving time reading more of your contentless prose.
Nathan (Comment#22644) October 27th, 2009 at 6:38 pm
You and I will have to disagree about this. As you would agree the carbon has been building up for decades. on my view building and living in areas that are below sea level ( assuming say a 1 meter rise ) qualifies as risky behavior. I prefer to put costs directly on the risky behavior. You want to preserve a status quo that I find objectionable. That status quo incourages risky behavior.
Anyways.. this thread has strayed away from the cherry picking issue, you’ll find that most of us lukewarmers don’t object to action. So you cant attack us for being anti science. You cant attack us for being anti action. We can debate actions. shrugs.
Now, can you agree that data and code should be free?
Can you agree that scientists should not have IP interests in climate data? Look at what is at stake.
Can you agree that we ought to put our best minds on the temperature series? upgrade the measurement systems?
Can you agree that 17 climate models of wildly different skill is a thing that ought to be corrected?
Bender
“Thank you, JFP & Simon. I think we have shown that there is more agreement than disagreement, as far as the wide spectrum of (ill-informed?) opinion goes. The magnitude of MWP “matters†for a couple of reasons.”
OK I agree, that if the MWP could be demonstrated to be significantly warmer than the CWP there would be an issue. As to the MWP being ‘ironed-out’ I remain unconvinced, there would need to be some real evidence of an MWP for it to be ironed-out, and it would need to be of a magnitude similar to or greater than the Holocene Optimum.
“JFP: here is why I am intrigued by Broecker (2001) and his far-reaching (but not global) 1500-year THC cycle (supposedly responsible for MWP-LIA cycling). First, as I said before, the GCMs do not come close to simulating this kind of high-order AR behavior. lucia has shown that in spades. Second, what is the possibility that the world’s oceans – and recall this is an area of active research by *very* smart people like Tsonis & Swanson – behave in part as a slow-motion Belousov-Zhabotinsky thermochemical oscillator? I leave this question “as is†and hope it piques lucia’s interest. (Or Tsonis & Swanson’s, for that matter.)”
I do think you need to look into this more. I can’t find anything else by Broecker on the MWP after his 2001 paper. He did lots on the THC prior to 2001, but I can’t see anything after. He says in the 2001 paper that there needs to be substantially more work done on it. I would be very interested on anything more about the THC (and any other oceanic conveyers for that matter).
Kuhnkat, What? Whatever. The call to action came before the Hockey Stick and I believe it exists without it – I don’t care if you don’t think there was any evidence prior to 1988.
Nathan,
“I understand that because of increasing CO2 we can expect the climate to warm at least as warm as it was during the Holocene Optimum, and most likely warmer than the previous interglacial. For these reasons alone, it would be wise to limit CO2 emissions.”
The HOLOCENE OPTIMUM??? The PREVIOUS INTERGLACIAL??? How do you come to this conclusion when you already admitted you don’t know how warm the MWP was in relation to modern?? What special basis do you have for estimating the magnitude of these two additional periods that didn’t work for the MWP??
It would seem, for all you KNOW, that things are MUCH WORSE THAN THEY WERE PROJECTED!!!
Then again everything could be nominal.
Bu then, you just don’t KNOW do you.
Let me make this simple. Your understanding is worthless based on your lack of useful information on the world you live in.
Steven
We’re not so different. I do think we need to change planning laws about ‘risky behaviour’ too. Australia is looking at that right now (down the East Coast).
So in the end I think it will be both acting simultaneously.
“So you cant attack us for being anti science. You cant attack us for being anti action.”
Actually what I was trying to do was to get you to actually publish your work so it’s easier to read. CA is a dogs breakfast as it stands. Publishing will formalise it, remove all the political spin, and hopefully force you to quantify the problem. I did however discover that Craig Loehle has actually recently published some stuff on the problems of proxy reconstructions, so good on him.
“Now, can you agree that data and code should be free?”
Well, up to a point. It is a good thing for data to be free, but it won’t always be possible immediately. For example a person who has collected data for their PhD or some large project will want to actually write all their papers before releasing the data (so that people don’t do it before them) – that can take time. Also replication in science doesn’t normally mean getting someone else’s data and checking they did it right, it’s more about getting your own data, doing the study, then seeing it you’re in agreement.
I, personally, don’t believe CA is just about “freeing the data”.
“Can you agree that scientists should not have IP interests in climate data? ”
IP Interests?
“Can you agree that we ought to put our best minds on the temperature series? upgrade the measurement systems?”
Well I don’t really understand what you mean. Is there, currently, a goal to dumb down climate science or to downgrade the measuring systems? Obviously they have budgets so can’t do everything – Didn’t NASA have a satellite planned that would orbit well away from the Earth to effectively measure the emission temperature of the Earth? I thought it was canned by GWB.
If by best minds you are suggetsing some other smarter people, then I suppose that would help. Who did you have in mind? Why do you think they are not involved at the moment?
“Can you agree that 17 climate models of wildly different skill is a thing that ought to be corrected?”
Well, this still suggests that nothing new is being done. It assumes there is no attempt to improve the modelling… Which is just not true. The current models are the best we have because no one has made a better one. Obviously it would be better if we had better models.
Can you also see that there is an asymptotic relationship between model improvement and the increase in our understanding. So improving models indefinitely gives a reduction in returns.
My “attack” in this case was just asking a question (initially) – sure it got heated along the way, but hey that’s the fun of the intertubes. It does seem to have come to a point of conclusion though. It would seem the only way the MWP becomes important is if it is warmer than the CWP (say around the level of the Holocen Optimum), I don’t know of any published work that would support that notion. The ‘desire’ to iron-out the MWP doesn’t really seem that great – there doesn’t really seem to be anything to iron-out. Why would you have to erase something you don’t even know existed.
Also, If you discredit proxy reconstructions or you believe that they are fatally flawed you lose any predictive ability about the MWP and still can’t tell if it was warmer than the present. If you are trying to improve proxy reconstructions… Well the best way would be to either do better reconstructions or write up in a statistics journal your method for doing one.
Kuhnkat
“The HOLOCENE OPTIMUM??? The PREVIOUS INTERGLACIAL??? How do you come to this conclusion when you already admitted you don’t know how warm the MWP was in relation to modern?? What special basis do you have for estimating the magnitude of these two additional periods that didn’t work for the MWP??”
I am not claiming the work as my own. Other people have done it.
It is in Chap 6 of the IPCC AR4.
Or at least that’s my understanding.
There is a much more compelling case for the last peak interglacial and the Holocene Optimum (which was the peak of this interglacial). Both are supported by sea level history and modelling the effects of the Milankovitch cycles. For example the last interglacial had two peaks of insolation (a few thouasand years apart) due to the orbital eccentricity and precession. But the Holocene optimum seems to have only had one (the two peaks happened around the same time).
Simon Evans,
” However, whatever doubts I have about the quality of these reconstructions, they are at least equalled by my doubts about any case I’ve ever seen put for a global MWP equivalent to today’s temperatures. My view is that we don’t have good enough knowledge of this either way.”
Sorry, I just can’t resist this one.
Why is the case for a GLOBAL MWP important?? If we can believe our current temperature records at all, this recent warming is a NH phenomenon. In GISS, HadCrut, RSS, and UAH, the SH and Tropics warmed substantially less than the NH and Arctic!!
Isn’t the assumption that everything is pretty much the same EXCEPT the current anthropogenic CO2 additions (and per Pielke Land Use??)
So, if the MWP was primarily a NH phenomenon, that would seem to reasonably match current conditions. Claims that a cooler SH in the MWP invalidates it would appear to be empty.
kuhnkat ,
Given that are simply being silly, I do not think that I will bother outlining what I think needs to be done. When you give some indication that you want a sensible discussion, I am perfectly happy to engage you in one. 🙂
Nathan (Comment#22656) October 27th, 2009 at 9:58 pm
Well, not to put too fine a point on it, but modeling for Wall Street pays better and nets more funding from the Fed. 😉 I’m sure other, similar examples abound…
Nathan’s opinions are irrelevant to me because he has shown himself to be impervious to logic and quantitative argumentation. I won’t be responding directly to anything he says. Yes, this is a dodge. A dodge that is easily justified.
David Gould says:
“When you give some indication that you want a sensible discussion, I am perfectly happy to engage you in one.”
.
To me, that is not a justifiable dodge. kuhnkat raises a point worthy of consideration:
“if the MWP was primarily a NH phenomenon, that would seem to reasonably match current conditions. Claims that a cooler SH in the MWP invalidates it would appear to be empty”
I think kuhnkat has given indication that we wants a sensible discussion on this point. (His example of nuclear strikes as pre-emption was reductio ad absurdum, and made for a bad analogy. That doesn’t mean the rest of what he says is non-sensical. Be reasonable.)
bugs (Comment#22589) October 26th, 2009 at 10:40 pm
“If Mann hadn’t done it, someone else would have”
hmm… “someone else” must be a clever person to come up with inverted varve series, decentered PCA, strip bark and instrumented temperatures pasted onto the end of proxy reconstructions, all in ONE piece of peerreviewedliterature!
bender,
I did not claim that everything he says is silly. I was expressly talking about the issue at hand: what I would recommend the world do. When he wishes to engage in a sensible discussion on that topic, I am happy to participate.
Bender :
“Bonus assignment: Do we *really* understand the causal mechanics of the D-O oscillation?”
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The short version is we *really* don’t .
I’ll attempt at a longer version .
I have already linked somewhere this : http://ams.allenpress.com/archive/1520-0469/43/5/pdf/i1520-0469-43-5-419.pdf .
I strongly recommend its reading for everybody interested by climate dynamics (connects to Tsonis too) .
.
Now let’s assume that it is right and that there exists a FINITE 6 dimensionnal climate attractor and I will show what can be deduced from this very existence fact .
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First it means that there exist 5 independent climate variables that fully and completely describe the attractor (e.g the invariant set of points in the phase space where the climate lives and will live “forever”) .
It might be the following : cloudiness ratio , precipitation , pressure , some radiative parameter (emissivity f.ex) and (non H20) GHG concentration .
Obviously this is only a guess for the sake of understanding and especially because I didn’t mention temperature .
Of course there may be an (almost) infinity of other dynamical parameters but they don’t matter because they are not independent by definition and that’s why temperature is not mentionned .
It is important to understand that , like in PCA , this is only a choice of coordinates in the phase space . I could take temperature as coordinate but then I’d have to throw something else out . Some coordinates may make the understanding easy some may make it untractable .
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Second it means that you need to get rid of space because we have unfortunately a system where matter , energy and momentum get transported . Yet as we talk about climate , it’s definition is valid for an invariant space only (f.ex “tropical” climate vs “polar” climate) . So the obvious solution is to spatially average the variables what in turn leads to the question what is the relevant spatial partition of the system .
Let’s assume we found it even if it is highly non trivial .
Then , as we are interested in temporal variations , we face a much harder question – are the spatial and temporal variations of our 6 variables independent ?
If no , it’s game over , the “climate” definition we took leads to an inconsistent being and I stop here .
If yes then we can go on . I would like to stress that this question is not YET definitely answered by theory but Fraedrich hints on it at the beginning of his §2 .
The GCMs implicitely assume that the relevant spatial partition is the size of a cell (e.g 100 – 200 km) but spatial and temporal variations are not independent .
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Third .
So now we have 6 purely temporal functions that are solution of a set of 6 non linear 1st order differential equations . Or , what is the same thing there is one 6th order non linear differential equation for each variable which is D6 [Pi(t)] = f(t) .
D6 is some non linear 6th order differential operator . Pi(t) is one of the 6 climate defining parameters . f(t) is all external “forcings” (Sun , orbital parameters , galactic rays , continental drift etc) .
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Fourth comes the interesting fact that the attractor is FINITE .
That means that every Pi(t) is bounded . Now if you had to draw a curve within a band , you would draw something that goes up and down . It would pseudo-oscillate . And if you look at the 3 Lorenz variables , that’s exactly what they do . They go up and down . So unless the solution of your ODE is a constant what is impossible because f(t) is not constant , ALL your Pi(t) go up and down .
The temporal average of the Pi(t) ? As time goes to infinity , this average goes to the middle of the band . For anything less than infinity it goes again up and down but with a smaller amplitude (that’s what W.Briggs aptly called “Smoothing ? Don’t !”) .
Also quite clearly “trends” are artifacts only due to an arbitrary choice of the time scale . While the curve of some Pi(t) (or its temporal average) might very well go up (or down) on some particular time scale , it is impossible to say for how long it will do it .
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And fifth I can answer now the question about the causal mechanics . The ultimate cause of everything and in particular of the existence of the attractor is f(t) – sum of all external .
With f(t) constant , the attractor has dimension 0 (a point) so the system will go to a state where all Pi are constant . That is also called equilibrium .
An important thing to realize is that f(t) can’t do anything “unusual” at least for the next 5 billions years when the Sun will dramatically change .
So it is fair to say that we have “seen it all already” and that the attractor is exceptionnaly stable for some 3.8 billion of years .
This OF COURSE doesn’t mean that the system itself doesn’t change . It does but must stay within the attractor all the time .
But Bender’s inquisitive mind might ask what is the causal mechanism of a particular part of the system like AMO .
Well then there is not 1 but 5 in my example – every one of the 5 ODE gives the causal link from the particular Pi(t) to the particular phenomenon of interest .
In this case AMO or any other pseudo periodical event is just a frequency that happens to suit to all Pi(t) and it is here that we meet Tsonis and the concept of coupled chaotic pseudo oscillators what is exactly the same thing I explained above but in another coordinate system .
That it is consistent with what Fraedrich is saying is amusingly shown by the fact that Tsonis ALSO needs about 5 pseudo oscillators to adequately describe the system 🙂
bugs (Comment#22649) October 27th, 2009 at 8:44 pm
Complete tripe. CO2 is not the only forcing on the climate, and it has never been claimed that it is.
So, now there is, indeed, other factors that need to be taken into account besides CO2. Good start down an evidence-based path.
Pretty soon, you’ll be talking about ocean cycles and albedo changes and natural climate variability during the MWP.
In my mind, we still need to be able to explain why it was warmer in the MWP. We don’t really have a driver for it.
If one looks at the longer climate record, there is evidence of chaotic changes that are not really explainable – everything from the Younger Dryas event (and the three other Dryas Events) to the MWP, the LIA, Roman Warm Period, the Dark Ages and the significant temperature spikes and drops within individual ice age periods.
On another theme : knowledge vs action
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The evolution honed in mankind the ability to act preferentially upon knowledge .
It is obviously a good attribute because we live better , longer and don’t get eaten by lions as often as we used 100 000 years ago .
The so called precaution “principle” is an antievolutionary lunacy because it asks us to act upon ignorance .
A person who says that we have an asteroid on collision course in 37 years will act upon knowledge .
A person who says there is a 0.001 % probability that an asteroid might be on a collision course in 37 years and asks for multi billion € action is a raving lunatic .
The real question will never be solved because there is no valid rationnally deduced probability level where one should act or one should not act .
As it is a completely subjective area , this principle delivers us in the hands of anybody , any lobby , any movement who would be poweful enough to impose us anything in the name of risk 0 .
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As far as climate goes , it has been nicely summed up by a person who wrote an open letter to his political representative .
Quoting out of head .
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“The Parliament will deliberate about laws , budgets and taxes limitting CO2 emissions and you will vote .
The reason of this debate is the supposed harmful effect of CO2 on temperatures .
Despite absence of scientific certainty about the far future , the precaution principle is evoked .
By the same token it can’t be excluded that the harmful effects will not take place and the measures voted represent a waste of public money .
In this case it is equally important that the laws , budget and taxes be cancelled and dedicated to more useful measures .
Therefore I ask you 2 simple questions :
– what is exactly the temperature you aim for ?
– how and when will you audit and evaluate the efficiency of the laws , budgets and taxes to make sure that the temperature target defined above is being met ?
Please be very sure to answer quantitatively and precisely the 2 questions because what is in stake are not only our votes but the credibility of the whole law making process .”
John F. Pittman (Comment#22646)
John,
Ok, I understand your logical construct. There are significant uncertainties other than temperature over that period anyway, and even more pertinently over the past and present century. We have good evidence of GHG changes at near-decadal resolution, but land use changes, aerosols and ozone are not as well known, and uncertainties in the history of solar irradiance and volcanic effects are still more significant. Most to the point, I think, we don’t even know current forcings (to the extent that net forcing could be anywhere between zero and +3W/m2), so little can be expected to be gained from attempting to estimate climate sensitivity from such periods. Our best information for an assessment of equilibrium CS comes from a comparison between the last ice age and the current interglacial.
What I think we might all agree upon is that we need better observations.Ocean heat content, especially the deep oceans, is not well enough known. Aerosols cannot be measured with the required accuracy with current satellites. The Glory mission will do so for tropospheric aerosols, but it’s now delayed to October 2010 at the earliest, and there are no further missions scheduled. There are currently no firm plans for a satellite to measure stratospheric aerosols effectively (the mothballed DSCOVR (Triana) satellite should have been doing this since 2003). I think we should be getting on with all of this urgently! If we want better temperature measurement systems, better proxy evidence and so on, that’s all part of the same case. This seems clearly to me to be one of the first set of ‘somethings’ we should do.
Simon Evans, I couldn’t agree more. And this is why I battle the damn-the-science-call-to-actioners. We’ve got to start measuring and modeling a number of things a lot more carefully. Precaution dictates this. Climate control is a very, very expensive proposition. You must know what you are up against before you start. Moving off of floodplains and out of the storm track is always smart, regardless of the climate. Eating veggies and riding your bike and getting off the grid and living in the dark is low-cost fantastic. But what if the small stuff isn’t enough? Isn’t anyone curious how climate *actually* functions, as opposed to how it’s modeled?
kuhnkat (Comment#22659) October 27th, 2009 at 10:09 pm
Why is the case for a GLOBAL MWP important?? If we can believe our current temperature records at all, this recent warming is a NH phenomenon. In GISS, HadCrut, RSS, and UAH, the SH and Tropics warmed substantially less than the NH and Arctic!!
Well, exactly so. In which case any specific MWP evidence needs to be compared with the temperatures in the same region and not be assumed to be indicative of a global average comparable to the current average. Apples with apples, please.
Consider Loehle 2007/revised 2008. He averages 18 proxies, not one of which is located much further south than South Africa (northern Pacific site SSDP-102 Latitude 34.9530). His revised conclusion is –
…the rise in 29 year-smoothed global data from NASA GISS…
from 1935 to 1992 (with data from 1978 to 2006) is 0.34 Deg C. Even adding this rise to the 1935 reconstructed value, the MWP peak remains 0.07 Deg C above the end of the 20th Century values, though the difference is not significant.
How do you like that? He’s compared his averaged proxies with the current global average!
Or consider the Heartland Institute’s ‘NIPCC Report’ 2009, which declares that –
“One can disprove the IPCC’s claim by demonstrating that about 1,000 years ago, there was a world-wide Medieval Warm Period (MWP) when global temperatures were equally as high as or higher than they were over the latter part of the twentieth century”
‘Global’, please note. And what does this ‘demonstration’ turn out to be? A counting up of the numbers of proxy studies which have a peak excursion indicative of a temperature higher than the current global average! Never mind where these studies were located, never mind the question of synchronicity, never mind that some of them equally suggest ‘warm peaks’ during the LIA, never mind that plenty of them indicate cold troughs in the MWP, and so on – just count ’em up!
In both these cases regional and latitudinal variation, which you rightly point out are considerable, are completely ignored. The implicit assumption is that any proxy from anywhere will do for comparing with today’s global average! Thus these comparisons make the assumption that the MWP was not only globally synchronous but also, bizarrely, globally consistent in magnitude.
Isn’t the assumption that everything is pretty much the same EXCEPT the current anthropogenic CO2 additions (and per Pielke Land Use??)
That’s not my assumption – solar irradiance and volcanic effect in particular are uncertain.
So, if the MWP was primarily a NH phenomenon, that would seem to reasonably match current conditions. Claims that a cooler SH in the MWP invalidates it would appear to be empty.
Let me be clear, I think there was an MWP. However, if the MWP matched current NH conditions (of which I would at least be doubtful) but did not match current (albeit lesser) SH warming then the MWP global average would still be lower, of course.
Simon Evans, now that you have come to this point, let me go a little further. This discussion belongs on Lucia’s site due to her work comparing models to “weather noise” and the projections from AR4. Santer et al has the quote, IRRC, “not inconsistant with the models.” Lucia has shown that the mean climate projection is at or near 95% falsification. The problem is that the Bayesian use of models, IIRC, “”all models have problems” was based on that at the time of projection the mean climate projections and increase in temperatures matched. As they should with backcasting.
However, if they no longer match, and Lucia’s work indicate that they don’t, and we cannot conclude that the CS from the interdecadal work of multi-proxies with tree-rings backcasts natural events such as MWP, then the Bayesian may, or more properly should fail, and the projections by the IPCC in AR4 are falsified. As Lucia has stated, one would expect some months ok, some falsified. If this flat period continues, it will make the projections less and less likely to be “not inconsistant with.” Since I am in doubt about psysic abilities, it is up in the air. BUT, this falsifies the claim of immediate action, the IPCC expectations for this decade, and severely calls to question “it is worse than we thought” articles using bin tricks and other statistical artifacts. By the same token, it could mean we should pay CO2 emitters.
I think there will be disagreement as to what the conclusions on what we should do from including a warmer MWP, than whether there was a warmer MWP.
John,
I think the current IPCC projections are most likely wrong, because they use presumed forcings which are most likely not accurate. Models suggest an energy imbalance of +0.75 +/- 0.25W/m2, whereas ocean heat content change suggests an imbalance of only +0.5 +/- 0.25W/m2. So I will not be surprised if the near-term (some years rather than decades) projected rate of temperature increase is below current IPCC projections.
However….
We must consider why the projections may be wrong, and the implications of that. If, as seems most likely to me (because the PDF is so broadly spread), aerosols (and their effect on clouds) are not being modelled correctly, then the extent to which they are masking GHG forcing has been underestimated, and the modeled ocean response time is too long. I don’t find this particularly comforting. Firstly, aerosol retention will reduce as the atmosphere warms further, and secondly the expectation would be of industrial production being cleaned up regardless of GHG mitigation (although one would expect some compensation at least from the reduction of black soot aerosols). The outcome of such would be a depression of projected temperature trend for a period followed by an inflation of it thereafter (because if ocean response is faster than modeled then the climate will respond more rapidly to a transient change in forcings).
Falsifying projected trends over the next few years does not put the planet back into energy balance. If we are to reach an anticipated average global temperature by 2070 rather than 2050, say, this does not ‘falsify’ the claim for current action, since it is not giving us a period of ‘grace’. Whatever we continue to put into the atmosphere continues to impact the energy balance.
BUT, this falsifies the claim of immediate action, the IPCC expectations for this decade, and severely calls to question “it is worse than we thought†articles using bin tricks and other statistical artifacts. By the same token, it could mean we should pay CO2 emitters.
The STR is a very simplified view of the climate, as it is polluted with the large background cyclical events, which is one of the reasons why the IPCC looks at much more than that when it publishes it’s report. The Arctic ice and glacier trends indicate change as predicted, as do other indicators such as crop plantings. Record highs outnumber the record lows, and this decade is easily warmer than any previous decade on record. Too much attention is being paid to noise, and I fail to see the point of the wiggle watchers.
It does not falsify the need for immediate action, since carbon added now is going to be acting as a forcing for, IIRC, a century. By the time the proof is unequivocal, it will be too late, and no one can argue with that.
bugs (Comment#22684) October 28th, 2009 at 3:05 pm
You wanna discuss how good the models of ice retreat are?
You wanna discuss how good the models of ice retreat are?
I’m just going on the observations.
http://www.geo.unizh.ch/wgms/mbb/mbb10/Abb1.pdf
I think I see a trend.
bugs:
Reference please.
The proof “for what”?
If we don’t require “proof”, then we must be acting on faith. Yes? (Faith being defined as the willingness to act on one’s beliefs in the absence of proof.)
If you are advocating we act without “proof”, certainly you won’t object when I describe you as a true believer in the secular religion of global warmism, will you?
bugs:
If you were to look at records for the previous four centuries you would see a growth in glacial ice too.
Is an ice age a good thing, and the absence of one a Bad Thing[tm]?
Also worth asking, what did the scientists monitoring glacier retreat ‘have’ to do to be consistent with the IPCC.
Carrick,
If we don’t require “proofâ€, then we must be acting on faith.
The physical sciences don’t do “proof”.
“If you thought that science was certain — well, that is just an error on your part.”
(Richard Feynman).
Or how about Popper? –
“… in science there is no ‘knowledge’, in the sense in which Plato and Aristotle understood the word, in the sense which implies finality; in science, we never have sufficient reason for the belief that we have attained the truth. … This view means, furthermore, that we have no proofs in science (excepting, of course, pure mathematics and logic). In the empirical sciences, which alone can furnish us with information about the world we live in, proofs do not occur, if we mean by ‘proof’ an argument which establishes once and for ever the truth of a theory.”
Or Bertrand Russell? –
“A religious creed differs from a scientific theory in claiming to embody eternal and absolutely certain truth, whereas science is always tentative, expecting that modification in its present theories will sooner or later be found necessary, and aware that its method is one which is logically incapable of arriving at a complete and final demonstration.”
Or Einstein? –
“It is the aim of science to establish general rules which determine the reciprocal connection of objects and events in time and space. For these rules, or laws of nature, absolutely general validity is required — not proven.”
It is actually the demand for “proof” which shows a misunderstanding of the scientific process. You can have absolute faith in the certainty that no proof will ever be provided!
Simon Evans:
I think that your focus on aerosols is probably misplaced. The models do a lousy job of predicting the known big variations (PDO, ENSO etc) and the radiation balance. The notion that we are a few tweaks and couple of fudge factors away from reliable climate modeling is silly. The IPCC output still seems like curve-fitting in service to an a priori canonically high forcing factor for CO2 and an unquestioned assumption of net positive water vapor feedbacks.
Your faith in alarmism is remarkable. If the warming does not keep up with the models then some factor must be interfering with the warming that must really be there. If the MWP did *not* exist (a flat handle for the hockey stick) and current warming (the blade) is unique therefore the measure of climate sensitivity is high. If the MWP *did* exist, then either there must have been more CO2 back then than we thought or modern warming is “even worse” because it is attached to a big natural wave or some other reason to always believe in a high CS regardless of which way the data breaks . At no time does it occur to you that (a) the models might indeed suck and (b) natural variability (or perhaps more accurately, our inability to explain climate) is significant.
I think that your focus on aerosols is probably misplaced. The models do a lousy job of predicting the known big variations (PDO, ENSO etc) and the radiation balance.
They don’t predict them at all, and have never claimed to. The latest research is now bringing out models that are intended to be able to model decadel level changes. We shall see how that goes. The ‘variations’ are actually cycles, so in the long term they are not relevant.
Re: TomVonk (Comments #22668 and #22672):
I like your posts but fear that the discussion will continue to veer toward other, more inane (quasi-cyclical) attractors.
Whenever I see statements like this:
“The ‘variations’ are actually cycles, so in the long term they are not relevant.”
I wonder if the commenter is a real person, or a sock puppet goading me into commenting.
.
Because we just spent umpteen exchanges establishing exactly why background/internal variability MATTERS. It was so excruciatingly obvious in the end that even Nathan had to agree. The more that you attribute current trend to intrinsic background variability, the less you are able to attribute it to CO2.
Bender proves he is six years old:
“Nathan’s opinions are irrelevant to me because he has shown himself to be impervious to logic and quantitative argumentation.”
Why would I care what you think of my opinions? Get over yourself mate. You could have gone off and found your Breocker links, demonstrated his further work on the MWP, but all you do is throw immature remarks around. Childish.
bugs says:
“They don’t predict them at all, and have never claimed to. ”
The model(er)s pretend to provide an accurate portrayal of natural background variability. They don’t do that; yett they won’t communicate that failing. Rather, lucia had to tell us that. So, basically, you are flat wrong. Good?
substance is good
Bender
” It was so excruciatingly obvious in the end that even Nathan had to agree. The more that you attribute current trend to intrinsic background variability, the less you are able to attribute it to CO2.”
This is really bending the truth bender (yes, a very appropriate name). The caveat here was that the MWP was warmer or as warm as than the Holocene Optimum. A truly remarkable and incredibly unlikely event, which is not supported by insolation changes. Presently there is no evidence for anything like that, so yes if we imagine that there is some imaginary factor that made the MWP and that is now doing the heavy lifting of the CWP then it won’t leave much room for CO2. But that’s not a very good theory is it? Why invoke unknown unknowns? Have you heard of Occam’s Razor?
And besides, you claimed my opinion was meaningless and here you are quoting me… Make up your mind.
George Tobin (Comment#22694)
I think that your focus on aerosols is probably misplaced.
You’re entitled to your opinion, and we must agree to differ. I repeat that current forcings could be anywhere between zero and +3W/m2 within the uncertainties. If you think that focussing on that is misplaced then, well, you have an opinion.
The models do a lousy job of predicting the known big variations (PDO, ENSO etc)
The models do not attempt to ‘predict’ the timing of such. Did you really think that they did?
and the radiation balance.
The models don’t ‘predict’ the radiation balance, they’re fed with a presumption of it.
The notion that we are a few tweaks and couple of fudge factors away from reliable climate modeling is silly.
I agree. You thought otherwise?
The IPCC output still seems like curve-fitting in service to an a priori canonically high forcing factor for CO2 and an unquestioned assumption of net positive water vapor feedbacks.
1) It is not a priori, it is derived, 2) WV feedback is not an “assumption” 3) do, please, skip the rhetoric – I think this blog is interested in discussing the science.
Your faith in alarmism is remarkable.
And your resorting to rhetoric when you ought to be discussing the science is, frankly, depressing.
If the warming does not keep up with the models then some factor must be interfering with the warming that must really be there.
No. If the evolution of temperature does not match model projections then self-evidently the model projections are wrong. Are you really objecting to my making that trivially obvious statement? If they are wrong then we have to figure out what is wrong with them. Do you disagree?
If the MWP did *not* exist (a flat handle for the hockey stick) and current warming (the blade) is unique and thus the measure of climate sensitivity is high.
Huh? I think you’re confused. A ‘flat’ past temperature history would suggest, in itself, lower rather than higher CS.
If the MWP *did* exist, then either there must have been more CO2 back then than we thought or modern warming is “even worse†because it is attached to a big natural wave or some other reason to always believe in a high CS regardless of which way the data breaks .
I didn’t understand that.
At no time does it occur to you that (a) the models might indeed suck
I said: “I think the current IPCC projections are most likely wrong”. Was that not good enough for you? Actually, I don’t think the models as such suck, I think our ignorance of current forcings sucks. Ok?
and (b) natural variability (or perhaps more accurately, our inability to explain climate) is significant.
You’re welcome to think that we are unable to explain climate. I’m interested in the science that addresses it, and I would quite appreciate being able to discuss that interest without you pushing for a food fight.
All the best, George :-).
Bender
“The model(er)s pretend to provide an accurate portrayal of natural background variability.”
What? They came up with a model and claimed that it did well. That’s not ‘pretending’. Make up your own model Bender if you don’t like the ones being used. It’s like whiney time at the local kindergarten.
And all you people who are unhappy with the accuracy of weather forecasts: you lazy asses should make your own models. Me and Nathan said.
Simon Evans,
I’m glad you continually emphasize apples-to-apples comparisons. What do you make of the argument that the infamous GMT flatline 2001-08 (and hence divergence from model prediction) is resolved by observing the absence of Arctic weather stations in the GMT calculation? This was discussed at realclimate under the “Mind the Gap” thread. They argue that the flatline is restored to an up-trend when you fill that Arctic gap with satellite data.
The model(er)s pretend to provide an accurate portrayal of natural background variability. They don’t do that; yett they won’t communicate that failing. Rather, lucia had to tell us that. So, basically, you are flat wrong. Good?
You are confusing modeling cyclical variations, with predicting when they will occur, with being able to model the complete climate. The ‘two box’ topic already established that it is possible to model the ‘big picture’ reasonably well from just the forcings, all you are arguing about is can they get the details correct and to what level. They don’t get the resolution that people demand, they never claimed they could.
bender,
…realclimate under the “Mind the Gap†thread…
I think it’s speculative. I think we need better data. I think we need to know what the freakin’ forcings are in the first place! I think I’m off to bed 🙂
bugs, do you really think I am confused? Is it at all possible you are not paying attention to what I said?
Bender
I take weather forecasts with a grain of salt – though they’re pretty good here in Western Australia (our weather is pretty consistent; Winter = wet and cool, Summer = hot and dry; Spring and Autumn are mirror images of each other, basically cooling and getting wetter -> warming and getting drier)… Oh wait that’s climate, not weather. Forecasting weather and modelling climate are a little different.
Oh and they really need you over at CA at the moment, seems Biffra made a response… Read very nicely too.
Nathan said “”The caveat here was that the MWP was warmer or as warm as than the Holocene Optimum. A truly remarkable and incredibly unlikely event, which is not supported by insolation changes. Presently there is no evidence for anything like that, so yes if we imagine that there is some imaginary factor that made the MWP and that is now doing the heavy lifting of the CWP then it won’t leave much room for CO2. But that’s not a very good theory is it? Why invoke unknown unknowns? Have you heard of Occam’s Razor?””
A caution about using an absolute such as “there is no evidence”” Evidence supporting climate change comes in many forms: historical documents. archaeological data, ice core data, botanical evidence, and other proxy data. Not all of this data is in accordance. Most of the Viking expansion
took place during what scientist refer to as the climatic optimum of the Medieval Warm Period dated ca, A.D. 800 to 1200 (Jones 1986: McGovern 1991); a general term for warm periods that reached there optimum at different times across the North Atlantic (Groves and Switsur 1991). During this time the mean annual temperature for southern Greenland was 1 to 3°C higher than
today. Without this amelioration in climate, it would have been impossible for some of the North Atlantic voyages to have taken place incIuding Eirik the Red’s Greenland discovery voyage (Jones 1986). from http://www.collectionscanada.gc.ca/obj/s4/f2/dsk2/ftp04/mq22551.pdf
The evidence 1)Evidence supporting climate change .. Not all of this data is in accordance. 2)During this time the mean annual temperature for southern Greenland was 1 to 3°C higher than
today. Thus using 1 and I do have evidence that MWP was warmer than CWP. It may be not be conclusive. But it falsifies your claim of NO evidence. One should words such as no very carefully. I think a better statement is that many accept MWP was not warmer. And I can point out the data has inconsistantcies, and some areas are known to have higher temperatures. I would then point out that the IPCC used that other world ALL< that should be used carefully to claim the following: Since some areas are known to be warmer and the data is inconsistant, the IPCC failed to support their claim of all ffedbacks reasonable and correctly varied to support their Bayesian claim of mean temperature especially the claim of no natural forcing can explain the modern half of the 20th century.
See what trouble a little no all can make. 😉
Nathan, do you see the experimental result here? My conversations with you inevitably descend to kindergarten level name-calling. My conversations with Simon stay at an adult level and we move forward as we exchange knowledge and ideas. I have a guess as to why this happens.
John F. Pittman (Comment#22710)
You are cherry picking! Do not, please, be so simple as to suggest that your proposed evidence of the temperature in Southern Greenland is “evidence that MWP was warmer than CWP”. Southern Greenland is not the world, regardless of the reliability of your evidence (which you don’t cite anyway in respect of your temperature claim). This is trivially obvious cherry picking, and we really shouldn’t waste further time on such.
G’night 🙂
bugs (Comment#22706) October 28th, 2009 at 7:01 pm
The ‘two box’ topic already established that it is possible to model the ‘big picture’ reasonably well from just the forcings, all you are arguing about is can they get the details correct and to what level. They don’t get the resolution that people demand, they never claimed they could.
The ‘two box’ topic showed that it is possible to make a curve fit which ties together the “model forcings” and the GMST (anomaly) more-or-less well, depending on how loose you set your standards.
bender (Comment#22704) October 28th, 2009 at 6:35 pm
And all you people who are unhappy with the accuracy of weather forecasts: you lazy asses should make your own models.
Working on it. In the meantime I can still complain about them, can’t I?
oliver: I don’t think Nathan will let you do that. He would advise you to invoke the precautionary principle and spend all your money on every possible means of anticipating all possible weather events. Even borrowing if necessary.
Bender I am perfectly capable of conducting conversation with others here too. The problem is your name-calling, which you start.
John F Pittman
“During this time the mean annual temperature for southern Greenland was 1 to 3°C higher than
today.”
Yes, perhaps it was in Southern Greenland…
“Thus using 1 and I do have evidence that MWP was warmer than CWP.”
indeed in Southern Greenland…
By the way, what reconstruction gives you those numbers for Southern Greenland? Where does the 1 to 3 degrees come from?
“But it falsifies your claim of NO evidence.”
Not really, as my claim was over Global temps and the evidence was supposed to show the MWP warmer than the Holocene Optimum, not just the CWP.
Bender
“He would advise you to invoke the precautionary principle and spend all your money on every possible means of anticipating all possible weather events. Even borrowing if necessary.”
It’s so funny that you get so upset when people misrepresent what you write… You are such a hypocrite.
You seem to have devolved into hyperbole now.
What do you think we should do abou this?
http://www.ias.ac.in/currsci/jun252006/1607.pdf
Simon:
Experimental sciences can and often do proofs in the sense of “beyond reasonable doubt”.
I believe in an open mind, but not so open that your brains fall out. — Arthur Hays Sulzberger
We ain’t there yet.
Good grief. Nathan. Honestly. Tell me your age and I will moderate my tone accordingly. Are you less than 20 or older than 70?
Experimental sciences can and often do proofs in the sense of “beyond reasonable doubtâ€.
We can measure gravity, quite well. But there are anomolies with measurements of space probes leaving the solar system, we are still researching the quantum level. Can you tell me how it works, “beyond reasonable doubt”, even after studying it for hundreds of years.
bender (Comment#22720) October 28th, 2009 at 9:09 pm
Good grief. Nathan. Honestly. Tell me your age and I will moderate my tone accordingly. Are you less than 20 or older than 70?
Maybe if you tell us your age it will explain something?
Bender
My age? Why, you want some action or something?
I have repeatedly told you I don’t care about your tone. I was adressing your remark that you couldn’t hold a decent conversation with me.
I guess you’ll be too busy over at CA now there’s some actual work to do for you. Best of luck, and remember – there is no conspiracy.
I take that to mean you don’t have a graduate degree. Maybe I should be less harsh.
I take that to mean you don’t have a graduate degree. Maybe I should be less harsh.
I take it you are not a climate researcher, will return the favour.
Simon Evans,
” However, if the MWP matched current NH conditions (of which I would at least be doubtful) but did not match current (albeit lesser) SH warming then the MWP global average would still be lower, of course.”
That is the issue. The papers listed at http://www.co2science.org do seem to support a MWP SH as high as current and a NH as high, or higher, than current. A few show higher, some lower. Of course, it would be amazing if the temp proxies showed consistent regional temps during the MWP as they are not now and I can’t think of any reason why they should be.
Since virtually all of the reconstructions that minimise the MWP and alledgedly match current highs (they actually don’t but still show substantial warming) have been cast into doubt by Steve McI’s tireless work, my leaning is still to an equal or higher MWP.
Now, let’s get my bias onto the table. I do not believe current temps are as high as the ground measurements would indicate. There is Watts survey, UHI studies, a number of other sites commonly panned by the AGW crowd, and 2 days ago I saw a reference to this site:
http://chiefio.wordpress.com/
After reading a number of his posts dissecting GissTemp and GHCN, I am now thinking that I do not have to call it a bias.
The likelihood that current reported temps are as high as claimed in comparison to historic temps is vanishingly small. The Hockey Stick and catastrophic AGW are dying the death of a thousand cuts by intelligent professionals and hobbyists on the net.
bugs:
No.
People like you who lack an open mind are unteachable.
Sorry.
No.
People like you who lack an open mind are unteachable.
Sorry.
That wasn’t a response to my point. We have been studying gravity for hundreds of years, we still don’t ‘know’ what it is that causes gravity. There are theories, but no ‘proof’.
Whoever brought up the precautionary principle I have a wager from mr pascal I would like to discuss.
bugs:
No duh.
“Is there a point to responding to anything you say?”, is the real question. But I’ll bite this once.
“What causes gravity???”
What does that even mean? That sounds like an ontological question, which is out of the demesne of physics proper.
The sort of question we ask in physics is “what is the law that governs gravitation”?
Newton answered it with the universal law of gravitation:
F = G M1 M2 /R^2
It’s true that Einstein later amended it with General Relativity, but the fact is that within the region that was tested by Newton and everybody up until the anomalous precession of Mercury was discovered… well that region still remains well explained by Newton’s original theory.
Einstein (and someday quantum gravity) extends the Newtonian theory at the boundary, and these more complex theories reduce to the older theory within the region where the classical theory is still relevant.
The same goes for Maxwellian E&M. That theory remains as useful and extant today as it was the day it was first drafted, it is at the quantum mechanical boundary where it gives way to the more complete theory of quantum electrodynamics, which itself has given way to the electroweak theory, and that someday probably to a unified electroweak + strong theory.
So yeah, we still discover new stuff, but it’s not like we have to throw out our old textbooks and replace them with new ones. Nobody uses quantum mechanics for purely classical problems, General Relativity for problems where Newtonian gravity are applicable and so forth.
The same goes for any empirical science. In the region where the theory is well tested and understood, the likelihood it will suddenly stop agreeing with measurement requires a level of open mindedness that results in your brain falling out and splattering on the ground.
We don’t generally use words like “proof”, the preference is “experimental confirmation”, and the method of statistical analysis is used to set a bounds on the likelihood that a measurement is (or is not) consistent with a given theory, with the general emphasis on empirical science being the requirement that a theory be falsifiable via experimental measurement.
But “proof beyond reasonable doubt” is the fundamental underlying theme of experimental science. Unlike legal trials, we have a much more objective framework for framing what constitutes “beyond reasonable doubt”.
The same general notions apply to climate. Fundamentally, there is nothing in climate that hasn’t been well tested separately, whether it be thermodynamics, fluid dynamics, etc.
The problem we have with climate is the range of scales go from the earth (6.4×10^6 m radius, 10^5 m thick atmosphere) all the way to the scale in which viscosity limits atmospheric turbulence (a few mm). We simply lack the computing power to put in a “first principles” model of the Earth’s climate, because a finite difference version of this model gives on the order of 10^25 elements. Plus the system of equations is probably hyperbolic and nonlinear with all of the problems associated with that….
The “new science” in climate is how you go from what is essentially an intractable problem to a simplified version that can adequately describe long-term climate changes associated with anthropogenic activity.
You basically has it wrong in that original comment I quoted, it’s not a question of waiting for more data: We have plenty of that. What is needed is more efficient use of the data we already have, and a better developed theoretical framework (namely improved GCMs) for analyzing that data.
Oliver
“I like your posts but fear that the discussion will continue to veer toward other, more inane (quasi-cyclical) attractors.”
.
Yes it seems so .
It has been my experience of the last 10 years that many (not all) people looking at atmospheric dynamics are stuck with naive and quite wrong ideas .
The ideas that there are (linear)”trends” and (quasi)”equilibriums” belong to it .
I wonder when people will begin to take seriously the fact that this system is REALLY dynamical (e.g varies at all time scales within a finite small dimensionnal attractor) .
Yet history of science teaches us that changes of paradigm take decades and are mostly forced by deviations between the data and the dominating paradigm which become more and more obvious .
So there is always hope .
.
As for the question about “acting” , there is also an increasing number of people who begin to wonder how one can “act” when there is no target whatsoever .
Of course acting on CO2 for the sake of CO2 alone would be stupid especially if there is a cost .
But those people want to act on TEMPERATURES , and there is not ONE , not a single one who would say what is EXACTLY the temperature they aim for .
This is a so antiscientific behaviour that one can only be flabbergasted .
.
Bugs
“We have been studying gravity for hundreds of years, we still don’t ‘know’ what it is that causes gravity. There are theories, but no ‘proof’.”
.
Well then you didn’t quite follow the scientific actuality in the last hundreds of years .
The cause of gravity is mass (or momentum-energy density what is the same thing) . This is quite proven because if you take a mass you have a gravitational field and if you move it or change it , the field varies . This translates in a mathematical construct deriving observable events (e.g trajectories) from energy-momentum density . This construct makes predictions with extreme accuracy which have been so far fully verified . So unless compelling experimental evidence arises , if it arises , the cause of gravity is mass .
Of course a sophist can always drive the causal chain in an absurd infinity by asking what is the cause of mass . And if the answer is the Higgs boson field then one can always ask what is the cause of the Higgs boson field . Etc ad absurdum .
Or for those who have Faith there is the First and Unique Cause of Everything at infinity of the causal “chain” .
But science is not sophism and it doesn’t work well when Faith interferes .
Nathan and Simon
Nathan said no evidence. I presented it. The first point about reconstructions is their CI’s. I presented evidence that pointed their is conflict in the data. Secondly, with one area showing such a warm period may mean that it is correct and the reconstructions must be used at the highest CI for MWP and lowest for CWP. This is within the range of possibilities.
However, Nathan said “no” evidence and this is plainly wrong. Not cherry picking, I was showing the problems with the “no” claim.
kuhnkat (Comment#22731) October 28th, 2009 at 11:49 pm
The papers listed at http://www.co2science.org do seem to support a MWP SH as high as current and a NH as high, or higher, than current. A few show higher, some lower.
A long time ago this thread was about cherry picking. You now point to ‘CO2 Science’, a site which has selected studies by screening for those which offer some case for a temperature peak at some time over a hundreds of years period. They have selected evidence to support the conclusion they want to advance. Is that the way you think science should be done?
Even having allowed themselves that ‘approach’, their case is risible. I’m not going to cherry pick my favourite, I’ll just look at the very first study they list on their ‘Project’ page –
http://www.co2science.org/data/mwp/studies/l1_coldaircave.php
They state: “Peak warmth of the Medieval Warm Period was as much as 2.5°C warmer than the Current Warm Period (AD 1961-1990 mean).”
Look at the graph. You will see a peak at about 870AD which they label MWP, suggestive of their 2.5C. Now look again at the graph and see what is indicated for 1500AD. Yup, that’s right, a peak suggestive of +3.5C, a whole degree warmer dipping into the Little Ice Age than during the MWP!!! You think the LIA was 3.5C warmer than present, do you?
Of course, it would be amazing if the temp proxies showed consistent regional temps during the MWP as they are not now and I can’t think of any reason why they should be.
Which is only one reason why we need multi-proxy studies rather than pointing to favourite aspects of individual proxies as above. I agree with you that regional indications cannot be taken as indicative of hemispheric or global averages – go tell the ‘CO2 Science’ folks that, wht don’t you?
Since virtually all of the reconstructions that minimise the MWP and alledgedly match current highs (they actually don’t but still show substantial warming) have been cast into doubt by Steve McI’s tireless work, my leaning is still to an equal or higher MWP.
I suggest you go ask Steve McIntyre directly what he thinks of CO2 Science ‘approach’ as illustrated above. Of course, in the case of ‘CO2 Science’ one doesn’t need to consider statistical analysis in order to see what’s up – I think a passably intelligent ten year old would spot the problem, don’t you?
Apart from all that, the paper shows a very short period for the peak. The current warming phase is significant for the fact that it won’t be going down, it’s locked in, unless something totally unexpected happens with solar. In the much longer term, Milankovich will take over.
quiet everyone, the sermon has begun. please, bugs, continue.
In the long run, there are greater forces than CO2. In the long run we are all dead. In the meantime, lets just look after ourselves. No need to binge drink every night, nothing wrong with being sensible and enjoying what we have. Also consider that this planet is not just about us, there are other life forms on it. They may not have read the IPCC reports yet, and remain unaware of the unintended consequences of our actions that they are facing.
Here endeth the sermon.
Nathan:
You don’t seriously argue that there are adverse health effects from breathing CO2 levels at (gasp!) 426 ppm. That article you cites was the silliest, most speculative alarmist drivel I have ever seen. The willingness to trot out this kind of crap is an indication that this may not be about science but confirming some weird need to intellectualize about fearful things even if they have to be invented. I want to see an actual medical journal attributing a specific health risk to increases in CO2 exposure in the range of a few 100s ppm.
Why is it that when some clown speculates (improbably) that New York will be inundated with 30 years due to global warming this scenario is supposed to invoke a somber consideration of the precautionary principle but when someone presents a far more reasoned analysis including possible benefits and better suggested uses of mitigation resources (e.g. Bjorn Lomborg) he must be demonized and his motives questioned.
It can’t mostly be about science. If the devastating work of Pielke Sr on the way we measure temperature is simply ignored with a eye roll, there is something else in play. It can’t be about science if people reflexively circle the wagons around the highly idiosyncratic data selection processes (to put it charitably) of the clique SteveM calls “the Team.” It can’t be about science to seriously believe in the endangerment of polar bears or the increase in storm frequency and intensity from AGW.
What is the kick in buying into this? Where is the buzz? I don’t get it.
“Here endeth the sermon.”
Can we be dismissed, pastor? Or do you still have to pass the collection plate?
Don’t make me holler
Don’t make me shout
Just turn them pockets
Inside Out
😉
Andrew
Simon:
This is South Africa, which need not strictly correlate with the global mean temperature, and certainly not with European temperature…. It certainly is within the realm of possibility of having a region that is out of sync with the global temperature for a such a short duration.
Also if you go back and look at historical material you do see occasional warming periods in Europe proper, including short periods of glacial retreat. See e.g. “The Little Ice Age: How Climate Made History, 1300-1850” by Brian Fagan. That certainly suggests that short periods of warming (e.g., perhaps from el Niño events) are consistent with the historical record.
I would say the biggest problem with many of the hockey-stick proxy-based reconstructions is they look like noise in the pre-calibration period: Namely no ENSO oscillations, no spectral peaks. Yet we know those are present in the the temperature record pre-AGW.
Carrick says:
“the biggest problem with many of the hockey-stick proxy-based reconstructions is they look like noise in the pre-calibration period: Namely no ENSO oscillations, no spectral peaks”
.
That’s not true. Many proxy-based studies have purported to show ENSOs and PDOs, the statistical and spectral proprties are not unlike ENSO and PDO. They’re not hard to find. Off the top of my head I remember one by R. D’Arrigo and another by F. Biondi.
bugs, tell the truth. the sermon never ends. please go on. we’re paying strict attention.
Here are a couple of figures and a reference to substantiate my comment.
First a comparison of GISS temperature (red) converted into a periodogram vs Mann’s 2008 reconstruction (blue). Plot here.
Individual proxies show similar features.
(Reference)
Bender to be more precise I was referring to multi-proxy studies such as Mann 2008. I haven’t looked at all of them, so I should have been careful about making blanket statements.
I agree that chronologies from individual proxies will exhibit periodic forcings, as does global mean temperature.
First, those spectra are not hugely different, certainly not in the way you describe. Second it appears the blue was smoothed and the red not. You must compare apples to apples. Third, you are cherry-picking Mann. I specifically mentioned two non-Mannian examples where the goal was specifically to pick up higher-frequency fluctuations attributable to ENSO and PDO. I could mention a dozen others. You can’t try to pull out decadal variation from a study designed to emphasize the lower-frequency secular variation. It’s an unfair test.
bender, I didn’t cherry pick Mann.
I was specifically thinking of him from the start when I said “hockey-stick proxy-based reconstructions”. Seriously, does another name pop in your mind when you see these words put together?
Secondly, the blue and red curves used the spectral analysis method. There was no smoothing of the blue curve to obtain that result. The fact that the blue curve shows no spectra peaks (just a smooth1/f^n spectrum) appears to be a problem to me.
Third, I was agreeing with you that the non-Mannian proxy reconstructions showed ENSO oscillations. So I have no idea what your objection is there.
Whoops, crosspost. Glad we’re in agreement.
Bender:
Mann produces a reconstruction with a resolution of 1-year, but we are to ignore…what?
Any fluctuations that are less than say 100 years?
Why would he bother to plot points at any finer resolution than 50 years if this were the case?
Carrick says:
“the blue and red curves used the spectral analysis method. There was no smoothing of the blue curve to obtain that result”
.
1. You think I don’t know that?
2. I’m talking smoothed input, not output.
Bender:
That isn’t a plausible explanation of the result.
The blue curve passes through the red curve, e.g., it resembles a smoothed version in the frequency domain not the time domain.
Had it been smoothed in the time domain, the smoothing algorithm would have acted as a low-pass filter and 1) you would still see the same spectral peaks but 2) they’d be much lower in value.
See this
Red line is original GISS spectra (detrended), green line is smoothed version (4th order butterworth, cut off frequency is 10-years). Time-domain smoothing simply attenuates the frequency response, it doesn’t smooth the frequency response.
The dT signal from the Mann reconstruction is not attenuated in amplitude, so time-domain smoothing does not appear to be a good explanation of this result.
I would also go further to suggest that observation of these spectral peaks should be a test of the validity of the reconstruction.
If you have developed a reconstruction method which can’t see them, then you have a largely untestable method, and that isn’t a good thing either.
You cling to your specious argument. I’m fine with that. The tests you’re showing do not answer the question. I’m fine with that too. You’re obviously smart enough to do the tests that matter.
.
I agree that reconstructions that target low-frequency signals do not contain strong ENSO and PDO signals. That you conflate proxy resolution (annual) and proxy frequency response (secular) is something you are smart enough to eventually work through yourself.
Carrick,
This is South Africa, which need not strictly correlate with the global mean temperature, and certainly not with European temperature…. It certainly is within the realm of possibility of having a region that is out of sync with the global temperature for a such a short duration.
You hardly need to tell me that – it’s very much my point. Given that the proxy studies selected by ‘CO2 Science’ (do you have no objection to selecting the results that suit an argument, btw?) are labelled as ‘MWP’ at peaks often hundreds of years apart, and given that there is no correlation established between them (by CO2 Science) suggestive of any common temperature signal, then it is most reasonable to hypothesise that these studies indicate regional peak anomalies that are asynchronous. Putting aside the question of whether these are good proxies for temperature, then yes, these selected studies present locations that are indicated as warm/warmer than current at some point over a centuries-long period tagged as the MWP (albeit that they might also indicate being warmer during the LIA!). Of course, the studies not selected (screened out because they didn’t suit the argument) indicate evidence of the opposite. What does this tell us about average global temperatures during such a period? Next to nothing without some objective analysis, I’d say, and probably even then not much until we have better proxy data for the SH.
I think I’m getting repetitive, so probably time to shut up 😉
On the contrary, Simon, I’d prefer it if you did not shut up on the topic of the 01-08 GMT flatline!
hey fellow lukewarmers..
What does the meeting ground of lukewarmers and CAGWers look like?
1. A discussion about the standards of science and fate of journals
2. discussions about policy under the conditions of uncertainty.
To my mind this meeting ground is a lot more fruitful than discussions about conspiracy and mindless adherence to journal science as it exists today.
Anyways, Tom Fuller ( fellow lukewarmer ) wrote a piece today. Enjoy.
http://www.examiner.com/x-9111-SF-Environmental-Policy-Examiner
Steven,
Interesting article from Tom Fuller. My reservation, though, is that it’s looking pragmatically at what can be done in the US or the UK, etc., to mitigate against local impacts. My concern (people can call it alarmism if they wish) is more to do with the impact in other parts of the world, both in terms of such local impacts and in terms of the knock-on effects upon less vulnerable regions (such as the US and the UK). We might have to spend quite a bit more on border control. We should maybe consider the implications of a heavily populated China eyeing up the sparsely populated, and climatically ‘improving’, areas of Russia next door, both being nuclear powers, of course. I can’t see into the future, but I don’t think we can just consider this as if we were geopolitical islands.
Btw, I’m a ‘not sure how much how soon’ warmer. Does that put me in a distinct category? I don’t have the apparent confidence of either the lukewarmers or the CAGWers! 😉
bender,
I’d prefer it if you did not shut up on the topic of the 01-08 GMT flatline!
They were good years for me personally, but I may be fooling myself by the randomness of my own experience ;-).
1. A discussion about the standards of science and fate of journals
Standards of Science – I thought these were already established.
Fate of Journals – Propaganda rags will exist as long as $Big Money/Big Politics$ wants to propagandize
2. discussions about policy under the conditions of uncertainty.
No Certainty = No Policy. Free people don’t need/want a phony governmental policy. Those are for Socialists or politicians with nothing better to do.
Andrew
Andrew,
No Certainty = No Policy.
Why does your country maintain military forces then, for example? Or why do you insure your house? Surely it is obvious that we generally consider it wise to develop policies without certainty? By all means question the risk analysis, but stating a “no certainty = no policy” mantra seems daft to me. There is never certainty in any scientific assessment, thus you would never have any policy informed by your understanding of such assessments.
Simon,
It is certain that a strong military will be needed. There are many wars currently being fought, all over the world. It is certain that weather or criminals will damage houses. We see these in the news daily. I see these things with my own eyes.
Science is supposed to provide certainty where none was before. That’s what science is about. If it doesn’t provide certainty, then it ain’t science, it’s speculation.
Andrew
Simon,
Science isn’t about what you *think* are the facts. It’s about what the facts *are*. Do you see the difference?
Andrew
Bender:
Simply because you claim it’s specious hardly makes it so. In fact you haven’t even come close to a proper defense of Mann’s reconstruction that would explain the total absence of any spectral peaks in his reconstructed temperature series.
The thing to focus on here is the calibration period is 150-years and the largest amplitude and simultaneously longest period peak we see in that calibration period (and in longer duration proxies) is around 54 years.
Think about that 150 year calibration period, ask how it gets done, then try and and construct a plausible mechanism where the 54-year peak isn’t present in Mann’s reconstruction, but is in the original proxies…
The proper explanation is not that he some how manages smear out the spectral content of the proxies while somehow preserving the amplitude of that spectral content.
No.
That’s absolutely not what I’m doing. I’ve asking why he is preserving annual resolution in his reconstruction if it is just noise. That seems like a reasonable question. If the shortest period for which your reconstruction gives something that is supposed to be temperature is e.g. 100 years, you should low-pass filter and decimate the data.
And while we’re at it, since you are making the claim (whether you intend to or not) that the short-period stuff is just garbage, you should point out where Mann states that in his paper.
Anyway, it’s not the lack of an annual (or even e.g. a 4.7 year) signal that bothers me, so your whole secular versus annual is just a distraction.
It’s the lack of the longer-term periods like the (approximately) 22-year and 54 year period signals that should make it through his processing but don’t that are the real red flags to me.
I think I’ve given what I think are pretty reasonable arguments for why one wouldn’t expect properly generated multi-proxy reconstructions to smear out the long-period oscillations.
I would go so far as to say (again) that these longer periods should be present in the final reconstruction and if they are not, the reconstruction has failed a validity test.
No, Andrew, none of those things are certainties, they are probabilities (for example, my house has never been damaged by weather nor by criminals to the extent of pursuing an insurance claim).
I will quote Richard Feynman again! –
“If you thought that science was certain — well, that is just an error on your part.â€
Excuse me, but I think that Feynman’s understanding of science is likely to be better than yours.
Of course, if you demand unattainable certainty before you would accept policy then you are very safe against ever having to change your mind.
Wars, weather, and criminals are certainties. We have armies, weather reports and overpopulated jails. Are you saying we don’t have those things?
Andrew
“my house has never been damaged by weather”
Other people’s houses have been, FYI.
Andrew
Feynman
Never heard of him. 😉
Andrew
Andrew_KY (Comment#22767) October 29th, 2009 at 5:18 pm
Wars, weather, and criminals are certainties.
Weather is, for sure! Damaging weather isn’t. I think this is a pointless discussion if you don’t understand the distinction between (high) probability and certainty. You are asking for certainty from climate science whilst thinking that high probability is certainty in other areas. If you want to demand high probability from climate science then say so.
Damaging weather is a certainty. The extent of the damage is up in the air, as they say. Rain, sunshine and wind are all damaging to your house. So are tornadoes, they are just more damaging to a greater degree if one hits your house.
Should I demand low probability from climate science? Is that what you demand?
Andrew
Ah, Andrew, so you have a house insurance policy that covers you against entropy…. 😉
Should I demand low probability from climate science? Is that what you demand?
Stop being silly, please. You know very well that I have suggested no such thing.
I think that we should assess probabilities when considering our actions. I trust (perhaps vainly) that you will not think otherwise.
If it doesn’t provide certainty, then it ain’t science, it’s speculation.
God doesn’t play dice with the universe?
Actually, Simon, I don’t know what my home owner’s ins. covers. I haven’t looked it in awhile. 😉
Yes, I agree we should assess probabilities when necessary.
I make a wager at Keeneland after I assess the probabilities my exacta box will hit vs the cost of the bet. (and after a coupla Bloody Marys)
Scientists make DISCOVERIES.
Andrew
bugs,
You really wanna talk about God? Sweet! 😉
Your Wisdom made the heavens and the earth, O Lord
You formed the land and set the lights
And like the sun Your love will rule the day
And stars will grace the night
Andrew
Simon, Feynman was not an experimentalist, and he did occasionally make errors.
I don’t think we disagree too much regarding the CO2Science thing…. I suppose it doesn’t bother me that they have an extreme POV, sort of balances the POV by pro-AGW blog sites.
In terms of errors on the site, it’s much easier to point out other people’s errors than to post your own work for scrutiny. You might just contact the blog, point out the problems, and see what happens.
I guess the only place there is a possibility of real daylight is where we should go from here policy wise. I’m not even sure what is there because I do advocate action myself, just not as extreme as Nathan might call for.
Carrick,
Expand the y-axis on your plot and then we’ll talk. (Later, I will ask you to standardize both series to a common variance.)
Carrick,
Thanks for understanding my ‘CO2 Science’ points.
In terms of errors on the site, it’s much easier to point out other people’s errors than to post your own work for scrutiny.
Shucks, some people put this argument to Steve McIntyre! I don’t have my own work in this field, I’m just an interested observer trying to figure out what I make of the evidence. I do my best to try to be objective, but my best is likely not good enough (no more than anyone’s).
You might just contact the blog, point out the problems, and see what happens.
Hmm – and let the Heartland Institute know that the basis of their argument is unreasonable? C’mon, this is politics, you know it is, on both sides.
I guess the only place there is a possibility of real daylight is where we should go from here policy wise. I’m not even sure what is there because I do advocate action myself, just not as extreme as Nathan might call for.
I think we should immediately be doing some stuff that is ‘good for the economy’ anyway – for example, the standards of housing insulation here in the UK are dreadful. As I’ve argued, I think the cost of better observations (and hence better understanding) is relatively tiny, and we should all push for that. Politicians are engaged in setting ‘targets’ the achievement of which are conveniently dated beyond their terms of office. I’ll be very surprised indeed if any developed economy actually shells out significant sums on mitigation over the next few years anyway. I think it would be a darned good thing if we could all agree on some sensible-anyway things to do and on the relatively small costs of advancing our knowledge.
But I’m posting too much again – g’night 🙂
bugs,
You really wanna talk about God? Sweet! 😉
Your Wisdom made the heavens and the earth, O Lord
You formed the land and set the lights
And like the sun Your love will rule the day
And stars will grace the night
So you have nothing to say of substance and accept my point.
bugs,
I’m sorry. You had a point? You usually don’t have one. 😉
Anyway, you were suggesting that God plays dice with the universe?
What evidence do you have the He does?
Andrew
I’m sorry. You had a point? You usually don’t have one. 😉
Anyway, you were suggesting that God plays dice with the universe?
What evidence do you have the He does?
Your naive belief that science is about certainty. Science cannot provide you what you want.
It’s a quote, Andrew, a rather famous one, from Einstein.
bugs,
You complained that I ignored you and now you won’t answer my question?
Science provides what I want from science. Speculation does not provide what I want from science.
Andrew
Science provides what I want from science.
Then you are not going to get much in the way of certainty.
“Then you are not going to get much in the way of certainty”
That’s life, though, isn’t it? Sometimes you get certainty, sometimes you don’t.
Andrew
Bender, here is the plot with expanded y-axes.
It is clear that Mann has applied a low-pass time-domain filter to his data (with roughly a 10-year period), but as I have pointed out, this simply smoothly attenuates the spectral amplitude, it doesn’t smooth over peaks (as can be seen with the green dashed line).
In terms of the variance… they were already nearly equal, if you compare the variances for the portion of the signal with periods greater than 10-sec. The “adjusted” Mann series is shown, but as you can see doing this doesn’t affect the outcome very much.
David Gould,
“Given that are simply being silly, I do not think that I will bother outlining what I think needs to be done. When you give some indication that you want a sensible discussion, I am perfectly happy to engage you in one.”
When you come up with a more reasonable attitude to taking action BEFORE you know what is actually going to happen I might be willing to listen!!
If science isn’t about certainty, then why claims like this one:
“In 2001, the IPCC said that there was a 66-90% *certainty* that humans were mostly to blame for rising temperatures since about 1950, but improvements in both the science and underlying climate data have boosted this confidence to 90% (re: certainty) in this latest report entitled Climate Change 2007: The Physical Science Basis.”
http://physicsworld.com/cws/article/news/26979
Andrew
Carrick:
Also, plot your amplitudes (y axis) on a log scale.
Simon:
Um… isn’t that what McIntyre is doing?
He’s doing original work and publishing it on the web for other people to scrutinize.
If he were just a lurker on other poeple’s blogs, like many of his stronger critics, then you’d have a point.
Bender:
I figured that’s what you meant and it’s done! 😉
That’s life, though, isn’t it? Sometimes you get certainty, sometimes you don’t.
Most science isn’t going to give you certainty.
I should have mentioned that I am only using the period of data prior to the calibration to the temperature (which I took to be pre-1850).
By way of comparison, here’s a plot where I’ve added the spectrum for the calibration period).
I don’t know what this really proves, but it does show that the Mann data for the calibration period has spectral peaks that are very close to what the real temperature anomaly data give.
bugs,
It is. The essence of science is observing, in certain fashion, that something is, or something is not.
This is how you build your knowledge database. You build it with things that certainly are, or certainly are not.
This points you in the direction you need to go with your unanswered questions. The scientist is the guy (or gal) who figures out how to answer them with certainty.
Andrew
Carrick:
1. Just like I told you: a lack of high-frequency amplitude in the recon is the only major difference. The middle and low are similar.
2. Which Mann recon series did you use? Are you sure it was not smoothed going in?
3. Did you standardize the variances? What’s the variance of the two input series?
Bender notice that the that Mann data for post 1850 have peaks (including in the region where there is roll-off from the filtering). There are no peaks in the other data set, just what appears to be band-pass limited 1/f noise plus what appears to be a high frequency (small period) noise floor.
I got the data from Steve’s website (recon.v1.tab), if you have another data source, I would be happy to use it instead.
The variances for the two data sets in the 0 to 0.1 yr^-1 interval were 0.04 C^-2 (Mann, pre 1850) and 0.07 C^-2 (GISS, Mann, post 1850).
Simon Evans,
you respond:
“You now point to ‘CO2 Science’, a site which has selected studies by screening for those which offer some case for a temperature peak at some time over a hundreds of years period. They have selected evidence to support the conclusion they want to advance. Is that the way you think science should be done?”
Then you go on to critique their selection of papers as NOT showing what they WANT!!! Are you sure of what they are trying to show??
I’m really sorry, but, you can’t have it both ways. Since they obviously have NOT CHERRY PICKED, by your own evaluation, I think we can dispense with that fallacious statement!!!
The reconstructions of MWP that have been done relatively Scientifically show a variable climate where some areas show higher, some same, some lower temps than modern. Then again, since I haven’t seen all the regional reconstructions compared to all the modern regional temp records, that is probably saying more than we know.
Of course, you did not respond to the information from the link I provided. Our real disagreement is probably the fact that I disbelieve the alleged current high temps. At the link I provided the author has done extensive work on identifying the actual stations that are used by GHCN and GISS. His posts show what was previously known around 1990, a large reduction in stations. He additionally is showing that around 2007 there was a decimation of the stations still left after 1990.
His analysis by latitude and area of these stations, while not providing exact temps, does an excellent job of showing a high probability that the temps are artificially increased. Look at the pattern of stations being added and then removed. The California stations are an obvious example. Stations with cold winters are all GONE. What is left are San Francisco and 3 stations in Southern California on the coastal side of the mountains. Having lived in the San Joaquin Valley, San Francisco, and San Gabriel Valley, this will cause an INCREASE in winter temps exceeding any decrease in summer temps.
He also analyzed Russia and a couple other areas with similar results, Cold stations being dropped in larger numbers than warmer.
Would you like to discuss THIS Cherry Picking of ridiculous proportions??? It goes directly to our real disagreement. Whether current actual temps exceed a realistic MWP!!!
Then again, maybe Hansen and associates are not Cherry Pickers, just really INCOMPETENT!!!!!
simon Evans
“No, Andrew, none of those things are certainties, they are probabilities (for example, my house has never been damaged by weather nor by criminals to the extent of pursuing an insurance claim). ”
Weasel words. Andrew talks about damage, you convert it to damage necessitating an insurance claim. Was he really talking about you house being blown over the rainbow or just the paint fading???
Simon Evans,
“They state: “Peak warmth of the Medieval Warm Period was as much as 2.5°C warmer than the Current Warm Period (AD 1961-1990 mean).â€
Look at the graph. You will see a peak at about 870AD which they label MWP, suggestive of their 2.5C. Now look again at the graph and see what is indicated for 1500AD. Yup, that’s right, a peak suggestive of +3.5C, a whole degree warmer dipping into the Little Ice Age than during the MWP!!! You think the LIA was 3.5C warmer than present, do you?”
Are you accusing them of a poor reconstruction?? Would you explain YOUR technical issues with this reconstruction?? I do not remember reading it and don’t have the time right now.
(please note you quoted PEAK MWP temps against 61-90 MEAN. I agree that isn’t saying much)
Does the possibility that the Climate can be much more variable than our records of the last 30 years would lead you to expect bother you??
Do YOU really believe that ANY proxies can be interpreted to give temps with that accuracy???
Bill Illis (Comment#22669)
So, now there is, indeed, other factors that need to be taken into account besides CO2. Good start down an evidence-based path.
For gods sakes, the IPCC clearly spells out what the other forcings are. No one has ever claimed CO2 is the only forcing.
bugs,
It is. The essence of science is observing, in certain fashion, that something is, or something is not.
I think you completely misunderstand what science is and how it works. Here is a copy of a previous post (not mine).
Or how about Popper? –
“… in science there is no ‘knowledge’, in the sense in which Plato and Aristotle understood the word, in the sense which implies finality; in science, we never have sufficient reason for the belief that we have attained the truth. … This view means, furthermore, that we have no proofs in science (excepting, of course, pure mathematics and logic). In the empirical sciences, which alone can furnish us with information about the world we live in, proofs do not occur, if we mean by ‘proof’ an argument which establishes once and for ever the truth of a theory.â€
Or Bertrand Russell? –
“A religious creed differs from a scientific theory in claiming to embody eternal and absolutely certain truth, whereas science is always tentative, expecting that modification in its present theories will sooner or later be found necessary, and aware that its method is one which is logically incapable of arriving at a complete and final demonstration.â€
Or Einstein? –
“It is the aim of science to establish general rules which determine the reciprocal connection of objects and events in time and space. For these rules, or laws of nature, absolutely general validity is required — not proven.â€
It is actually the demand for “proof†which shows a misunderstanding of the scientific process. You can have absolute faith in the certainty that no proof will ever be provided!
Simon Evans’
“Falsifying projected trends over the next few years does not put the planet back into energy balance. ”
And what is your evidence that the earth ever was or ever will be in energy balance??
What is your evidence that it has dangerous excess energy that must be somehow dumped before we are safe??
For a man who seems to claim to be a lukewarmer you sure do have a lot of bogus Alarmist talking points!!!
bugs,
sciâ‹…ence
–noun
1. a branch of knowledge or study dealing with a *body of facts* or *truths* systematically arranged and showing the operation of general laws: the mathematical sciences.
2. systematic knowledge of the physical or material world gained through *observation* and *experimentation*.
What you want to do is modify the definition of science to accommodate your religious belief in AGW. Doesn’t fit unless you change the meaning.
Andrew
Did you read those quotes? You are the religious one.
bugs (Comment#22801) October 29th, 2009 at 9:19 pm
Well done bugs.
( although I would point out a glaring inconsistency in russel )
OMIGOD I agree with Bugs on something! So that means we will never have capital P Proof (i.e. unarguable) of CAGW only little p proofs that we each weigh on our own scales.
Posh. Plenty of things can be proven. Granted most of those are in the category of tautologies or thing God knows are tautologies but enjoys watching us squirm trying to prove or disprove them-the latter are “mathematical theorems”. But some things can be shown so rigorously that it would be absurd to say they aren’t “proven”.
OMIGOD I agree with Bugs on something! So that means we will never have capital P Proof (i.e. unarguable) of CAGW only little p proofs that we each weigh on our own scales.
Hence the use several sources of evidence. In regards to Pittmans argument, the cooling stratosphere as a ‘fingerprint’ is significant.
kuhnkat (Comment#22797)
I pointed out that even after they’ve cherry picked the studies they want to reference they still have very uncertain evidence of what they claim. You appear to accept every criticism ever made of Mann et al. yet cannot see cherry picking of results (not of instrumental correlation, as discussed in Lucia’s OP) when it’s staring you in the face.
Of course, you did not respond to the information from the link I provided.
Nope, because i) it was yet another topic on a thread which is already way off topic and ii) anyone so ignorant as to suggest that the GISS record is being cooked to show “a runaway greenhouse scenario”, as does the author of the blog you link to, strikes me as being too stupid to waste my time on (you do know what a runaway greenhouse scenario would be, yes?). I’ve made my points about the obvious distortions at CO2 Science which you seem incapable of seeing, so there’s no point wasting my time on further ignorance and distortion that you link to. In passing, though, I’ll make the obvious points that
i) Hansen has nothing to do with GHCN’s network,
ii) if the GISS record was being ‘cooked’ as the conspiracy theorists maintain then it would clearly diverge from other temperature records. See here for the whole satellite period(the offsets are simply different reference baselines):
http://www.woodfortrees.org/plot/gistemp/from:1978/trend/offset/plot/rss/from:1978/trend/plot/hadcrut3vgl/from:1978/trend/plot/uah/from:1978/trend
UAH diverges somewhat, but you’d best go figure out how RSS and HadCRUT are being cooked as well, or maybe ask Hansen why he’s such a failure as a fraudster – all that work and no improvement!
iii) You seem to be confused over the measurement of anomalies and absolute temperatures. Since temperature minimums have risen more than maximums, your suggestion that dropping any cold winter stations will inevitably introduce a warming bias is spurious.
kuhnkat (Comment#22798)
Weasel words. Andrew talks about damage, you convert it to damage necessitating an insurance claim.
No, I introduced the idea of insuring against damage. Read more carefully.
kuhnkat (Comment#22799)
Are you accusing them of a poor reconstruction??
They (‘CO2 Science’, that is) haven’t done a reconstruction.
Does the possibility that the Climate can be much more variable than our records of the last 30 years would lead you to expect bother you??
Of course the climate has varied more than in the last 30 years. What an odd question!
Do YOU really believe that ANY proxies can be interpreted to give temps with that accuracy???
No. I’m glad you seem not to either – so please go tell ‘CO2 Science’ that they are engaging in deceit by suggesting that they can! And do, please, stop shouting.
kuhnkat (Comment#22802)
And what is your evidence that the earth ever was or ever will be in energy balance??
I’m not going to write a post on basic thermodynamics, kuhnkat. Try Wikipedia.
What is your evidence that it has dangerous excess energy that must be somehow dumped before we are safe??
“Excess energy”? Hmm. Do you understand the ‘greenhouse effect’? It’s not a good name for it, but it will have to do now. The matter of GHGs being warming influences is not disputed by any climate scientist that I know of (not Lindzen, not Spencer…). The question of how much warming is disputed, of course.
For a man who seems to claim to be a lukewarmer you sure do have a lot of bogus Alarmist talking points!!!
I have not claimed to be a ‘lukewarmer’. Read my posts. As for your use of pejorative terms, that tells us about you rather than about me.
Kuhnkat :
“And what is your evidence that the earth ever was or ever will be in energy balance??”
Nobody has this evidence because it is trivial that the Earth is NOT in energy balance and has never been .
It is even the whole point of the dynamics that precisely the Earth system is permanently out of equilibrium .
The spatial and temporal patterns that are observed in the dynamical parameters are precisely the consequence of non equilibrium dissipative processes .
TomVonk (Comment#22813)
Of course it is never at a point of stable equilibrium, since the forcings are in flux. However, it moves towards a potential equilibrium for any given state of forcings, and thus the addition or subtraction of a forcing changes the potential equilibrium.
“Did you read those quotes? You are the religious one.”
Did you read the definition of science?
Yes, am religious. However, you are the one mutiliating the defintion of science to make it include the Church of AGW, not me.
Andrew
“proofs that we each weigh on our own scales.”
‘Little’ proofs and our own scales?
You guys are just yankin’ my chain now. No serious person thinks this is science. 😉
Andrew
Simon Evans
“Of course it is never at a point of stable equilibrium, since the forcings are in flux. However, it moves towards a potential equilibrium for any given state of forcings, and thus the addition or subtraction of a forcing changes the potential equilibrium.”
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Does it ?
And what would this hypothetical “potential” equilibrium be ?
Hydrostatic equilibrium ? Radiative equilibrium ? Chemical equilibrium ? Vapor-liquid equilibrium . Mechanical equilibrium ? Thermodynamical equilibrium ?
The truth is that it is all of them and neither specifically .
There is not a SINGLE place on the Earth that is in radiative equilibrium and it doesn’t tend to any “potential” invariant point in the phase space either .
The night half is violently out of radiative equilibrium as is the day half . Equators are that as well as poles too .
Are they “nearer” to some potential equilibrium today than yesterday ?
Of course not . They may even be farther .
It is surprising how many people still don’t get it – we have here a permanently out of equilibrium dissipative dynamical system .
Such systems are permanently overshooting and undershooting “potential” equilibriums .
In non linear dynamics one simply learns to live with the fact that many complex system are out of equilibrium ALL the time and that the patterns and behaviours they exhibit have nothing to do with any “potential” equilibriums in systems that are just theoretical constructs that don’t exist in the real world .
In reality what the system does is to try to dissipate energy as efficiently as it can and it will do that in many possible ways which are all far from any “potential” equilibriums .
And of course this happens regardless if the external “forcings” are constant or variable .
lucia, are there two IPs using the name “bugs”?
Tom Vonk,
It took a long time for ecologists to understand this about their world: it’s a dynamical system, out of equilibrium, with no chance of ever getting there because of disspative lags. It amazes me how far behind the climatologists are. Usually it’s the ecologists lagging behind everyone else.
bender–
Yes. There are two IP addresses using ‘bugs’. However, that’s pretty common. Many people post from work and from home. I did a reverse IP and based on location, that may be the case with bugs.
Simon Evans (Comment#22814)
“Of course it is never at a point of stable equilibrium, since the forcings are in flux. However, it moves towards a potential equilibrium for any given state of forcings”
How fast does the ocean move toward this multi-dimensional thermo-chemical equilibrium state, Simon? Do you really think it ever gets there?
bugs’ style changes home vs. work
bender–
TCO’s style also changed at home vs. work. I think alcohol was involved.
Lucia has probably noticed that I have posted from several different IP’s. There’s my laptop, my father’s office (where I am right now), University, and a few other places from time to time.
But I’m the same person with what I think is the same style regardless.
Andrew_FL–
I rarely check IP’s. I only checked TCO’s when I was moderating him. I only checked bugs because bender asked. But many people post from 2 or more IPs. Heck… mine changes from time to time.
Bugs’s IPs are both on the same continent and he always enters the same email I can’t guarantee he is not two people, but his tracks are consistent with being 1 person. 🙂
bender,
Do you really think it [the ocean] ever gets there?.
No, nor will it ever, if only because the sun’s a changing star. However, I think that over thousands of years the ocean has mixed to get ‘most of the way’ following major changes, as in the case of ice ages, for example. Even then, though, there will still have been solar cycles continuing to alter the conditions.
I’m away until tomorrow, so cheerio for now.
Bugs,
“the cooling stratosphere as a ‘fingerprint’ is significant”
Yes, but a significant portion of that cooling may also be caused by falling sulfate aerosol load in the stratosphere, due to lack of major volcanoes and falling sulfate emissions from coal fired power plants in most of the developed countries. An overlay of NASA’s estimate of stratospheric sulfate aerosol opacity and RSS’s temperature of the lower stratosphere shows a very strong correlation. It could be just coincidence of course, but the correlation is so good that causation may be involved. There may be less to the stratospheric cooling ‘fingerprint’ from greenhouse gases than meets the eye.
Simon,
Re-read all of Tom Vonk’s postings, both here and at CA. The failure to achieve equilibirum has nothing to do with external forcings perturbing the system. The systems perturbs itself. The ocean perturbs the atmosphere, and so on.
Simon Evans (Comment#22812)
“as does the author of the blog you link to, strikes me as being too stupid to waste my time on”
You have a problem with what E.M. Smith writes take it up with him before making comments like this.Try reading what he says before making judgements. I’d say E. M. Smith has more brains then you’ll ever have but I’m too polite.
Bender
.
“The failure to achieve equilibirum has nothing to do with external forcings perturbing the system. The systems perturbs itself. The ocean perturbs the atmosphere, and so on.”
Bender I think it will take decades before that sinks in .
.
Poincaré has written almost exactly 100 years ago :
“You are asking me to predict events that will happen . If I was infortunate enough to know the laws of these events I could only answer after having tried untractable computations and in the end I would have to admit that I cannot answer . But I am lucky and I ignore these laws and that’s why I can answer immediately . And amusingly enough I may be right .”
This was in relation with the very simple 3 bodies problem which Poincaré has proven to be unpredictable .
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Lorenz has (re)discovered and studied deterministic chaos already 40 years ago . There is the integrable hamiltonian system theory and the impressive KAM theorem . The ergodic theory exists practically since Boltzmann .
.
Yet despite all that , today in 2009 , there are still (too) many scientists that have no training whatsoever in non linear dynamics and lacking that , continue to use 19th century equilibrium physics .
Their vision of such obviously chaotic systems like the Earth is the one of a small ball in a bowl that has 1 equlibrium point and stays there all the time unless you (=external forcing) push it a very tiny bit away from the bottom in which case it will immediately want to go there again .
The system in the real world doesn’t do that at all and has never done .
It infinitely roams within its attractor where EVERY single point is out of equilibrium and neither point of its trajectory is “nearer” or “farther” to some hypothetical “potential” equilibrium point(s) .
.
Also negative feedbacks NECESSARILY dominate chaotic systems because it is the existence of energy dissipation (= negative feedback) which allows the existence of patterns and structures .
A system dominated by positive feed backs beside the obvious divergence problem would immediately destroy any attractor and could not exhibit patterns and structures .
Even such basic results are ignored .
The climate is is dynamic equilibrium hence evolution is possible. Failure to recognize this equilibrium is due to cherry picking short time intervals. This is why the recurring external forcings do not create runaway heat or cold. It is also why Lindzen is likely right that feedbacks dampen CO2 warming… it is a fundamental feature of dynamic equilibrium.
Tom Vonk said it much better. All I know I learned in geology classes and flight school. Alarmists think planet earth is a helicopter while lukewarmers think it as a fixed wing aircraft with modest dihedral.
Howard
.
I am not sure what you mean by “dynamic equilibrium” .
An equilibrium is 1 special point in the phase space .
It may be time dependent or independent but it is always 1 point only and all trajectories finish at that special point .
There may be a cycle (closed curve) which corresponds to a periodical system where the system repeats exactly the same states over and over .
Everything else is per definition out of equilibrium in any meaning of the word .
Simon Evans (Comment#22828) October 30th, 2009 at 8:02 am
The sun could be perfectly stable and I could still show you detailed measurements of the upper layer constantly mixing and restratifying — never close to anything you’d want to call an equilibrium.
TomVonk (Comment#22832) October 30th, 2009 at 10:47 am
To be fair, I don’t think most climate scientists would defend the statement that positive feedbacks can continue to dominate the climate system for very long (although it is not clear that all have thought about it very hard).
The classical statement seems to be that we can approximate the trajectory meaningfully over a “short enough” time that which we claim positive feedbacks (continue to?) dominate and yet the time is “long enough” that something “significantly harmful” can happen.
Tom
I think he means what engineers call “pseudo-equilibrium”. There are lots of systems that are never in equilibrium per-se, but the notion that some sort of equilibrium exists, and that systems move toward it is useful
For example, high Reynolds number flow past an airfoil is never at “equilibrium”. Strictly speaking, due to chaotic features associated with vortex shedding at the trailing edge of the airfoil, the instantaneous lift on the airfoil varies with time even if the airfoil is moving at constant speed through air and has been for ages. But the concept of “pseudo-equilibrium” with a constant steady value of lift is useful when analyzing some problems.
The same concept might be useful for climate. (Or not. It all depends on what problem one is trying to address.)
Lucia
.
Ok I see . Makes sense . I would never call it equilibrium even pseudo because it may lead to confusion with real (pseudo)equilibriums . But the analogy is good .
For me it is again Reynolds averaging all over 🙂
You know my opinion about it -there are strictly limited parameter domains where it gives useful answers that can’t be generalised outside of the domain .
We are lucky , planes are in there as long as they fly in the air and at reasonable speeds .
It might be useful for the climate if and only if the climate attractor had a huge number of dimensions (e.g a huge number of degrees of freedom of the system) .
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Sofar the evidence like f.ex the paper I linked but there are more in the same vein rather point to a small dimensional attractor (5 or 6 dimensions) .
And in this case the “plane” method cannot work and will not work .
.
Not mentionning the fact that the space variables are not so important for wings (scales of interest only a few meters) while they are paramount for the Earth (scales of interest of thousands of km) .
I have still met nobody who would be able to explain how he would relevantly partition Earth space to talk meaningfully about “climate(s)” and its/their evolution(s) as function of time only .
What sense does it make to ignore spatial autocorrelations when they are obviously there as they rightly should in any system where energy , mass and momentum are transported ?
Oh yeah… BTW, that C02 causes Global Warming thing we were talking about?
It’s not that. It’s something else. Whoda thunk? Iddnthat a kick in the pants? 😉
“The effects of a critical greenhouse gas on global warming have been significantly underestimated, according to research suggesting that emissions controls and climate models may need to be revised.”
http://www.timesonline.co.uk/tol/news/science/earth-environment/article6895907.ece
Andrew
You know what this means, don’t you guys? A Whole New World of Squiggly Lines to Look At. The fun we’ll have! Mmmm mmm! 😉
Andrew
TomV–
It is sort of like Reynolds averaging all over– but without actually doing algebra. 🙂
Oh… it might be useful even if there are fewer numbers of dimensions. Think of something like Bernard cell convection. Then, crank up the heat rate just a little so things get a little more chaotic, but you still don’t get full blown turbulence. One could still think of some sort of “pseudo-equilibrium” and it would be useful for some applications.
I took a double-diffusive convection class in grad school. Our focus was solar energy applications including ponds. The notion of “Reynolds average” of the behavior could be useful if you were trying to estimate the rate of heat loss over… oh… months. But by the same token, if you were a micro-organizm living in the pond, it wouldn’t be too useful for predicting whether you were going to see a sudden warm upwelling or a cold down welling or whatever. Also, “Reynolds averaging” was not particularly useful as an analytical method for predicting the actual flow structure.
So, the problem was that the averaging operation was only potentially useful as a filter applied after trying to predict a flow field. Even then, it was only useful when discussing a subset of applications.
Dynamical equilibrium vs. statistical equilibrium. Very different things. Climatologists assume they’re identicial. Or, rather, that the existence of one implies the other. But of course chaotic systems may be bounded, which, unfortunately, makes them appear as though they’re amenable to Gaussian statistics. They’re not. So sorry, Gavin.
Andrew_KY:
A pro-CO2 bias of 33%, how can that possibly be? The physics is rock-solid. All of the estimates are fully constrained by robust experimentation.
bender,
With a novel but robust mixture of probabilities, we can be certain (although that is not our objective) that we are improving upon previously undervalued but useful estimates. 😉
Andrew
Lucia
.
“Think of something like Bernard cell convection. Then, crank up the heat rate just a little so things get a little more chaotic, but you still don’t get full blown turbulence. One could still think of some sort of “pseudo-equilibrium†and it would be useful for some applications. ”
Well one would be better inspired to think of it like a stable attractor well knowing that the system itself is far from any kind of equilibrium .
It is because it is far from equilibrium that it forms the cells .
But then you could move one of the parameters (f.ex indeed the heating) by an infinitely small amount and you would see the structure completely destroyed and a macroscopical global change happen . I am sure that you have seen that too .
And you are absolutely right the low dimensionnal states are more interesting (and much more difficult to understand) than the fully developped turbulence .
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But I broadly agree with the spirit behind what you say even if I prefer terms coming from non linear dynamics .
It’s what I have been saying all the time – while in non linear out of equilibrium dissipative systems useful and most importantly true things can be said about the stability , existence and topology of ATTRACTORS (you would say Bénard cells) , it doesn’t make much sense and is generally useless to ask for trajectories (e.g temporal evolution of dynamical states) .
That was btw the sense of the Poincaré quote I gave above .
In low dimensional cases it’s illusion anyway and in high dimensional cases only statistics can help provided that the system is ergodic .
.
Clearly if you have taken classes in diffusive convection , you had insight in pattern formation and the formalism of dissipative systems so you are familiar with what it means when a system is permanently out of equilibrium .
Or multiphase mixing flows (I seem to remember that you worked in there too) .
Alternatively the study of non linear dynamics gives the insight and formalism for structures and behaviour of out of equilibrium systems in the phase space .
I really wonder what kind of classes took the “climate” scientists but the majority is obviously unable to conceptualize genuine out of equilibrium systems .
bugs said “Hence the use several sources of evidence. In regards to Pittmans argument, the cooling stratosphere as a ‘fingerprint’ is significant.” Several good posts follow showing that the cooling stratosphere may not be significant for understanding or for support of an argument. If I get a chance this weekend will post some fun stuff that the posts after yours get into.
Andrew_KY (Comment#22840) October 30th, 2009 at 12:49 pm
Oh yeah… BTW, that C02 causes Global Warming thing we were talking about?
It’s not that. It’s something else. Whoda thunk? Iddnthat a kick in the pants? 😉
“The effects of a critical greenhouse gas on global warming have been significantly underestimated, according to research suggesting that emissions controls and climate models may need to be revised.â€
You have completely misrepresented what that story means.
For one, it is the climate researchers who have come up with that information, no one in blogland did, it is part of the ongoing research, it does not invalidate CO2 as a GHG, rather it makes out that things are going to be worse than was expected, as other gases will be adding to the forcings more strongly than we thought. That is, it’s not a case of joy on your part, but concern that the current projections are going to underestimate AGW.
Tom: Thanks, I enjoy reading your precise and detailed explanations. In aviation, fixed wing aircraft are designed to be dynamically stable. That means that you can deflect a control input, release it, then the aircraft will eventually return to the previous condition after a series of oscillations. In geology, “stuff” fluctuates all the time around a mean value, a slowly declining value or a slowly increasing value. Nothing I have ever seen in geology is ever in static equilibrium.
This type of gut level understanding of dynamic physical natural science is why most all geologists over 40 don’t go for the scary AGW scenarios. The younger ones have been contaminated by the conversion from geology departments to earth science institutes and the mixing with muddleheaded geographers and environmental studiers. Arm-waving is slowly replacing field studies as the clean fingernail set slowly takes over.
SteveF (Comment#22829) October 30th, 2009 at 8:05 am
Bugs,
“the cooling stratosphere as a ‘fingerprint’ is significantâ€
Yes, but a significant portion of that cooling may also be caused by falling sulfate aerosol load in the stratosphere, due to lack of major volcanoes and falling sulfate emissions from coal fired power plants in most of the developed countries. An overlay of NASA’s estimate of stratospheric sulfate aerosol opacity and RSS’s temperature of the lower stratosphere shows a very strong correlation. It could be just coincidence of course, but the correlation is so good that causation may be involved. There may be less to the stratospheric cooling ‘fingerprint’ from greenhouse gases than meets the eye.
You put up your correlation against my prediction with a physical basis. Guess who wins?
“it makes out that things are going to be worse than was expected”
Of course, bugs, of course. I never doubted for a moment it was otherwise.
Andrew
Howard (Comment#22834):
“Alarmists think planet earth is a helicopter while lukewarmers think it as a fixed wing aircraft with modest dihedral.”
WOW, well said!
That precisely illustrates why one group insists that SOMEONE (namely, government) must immediately take the controls. And the other group is fine with scrounging around in their Jepp bag for a few moments looking for the correct approach plate.
The helicopter is correct.
http://scienceblogs.com/startswithabang/upload/2009/04/how_could_we_affect_the_earth/historical02.gif
If you look in geological time.
Bugs-first of all, your “fingerprint” is not a “fingerprint” at all. The vast majority of the stratospheric cooling in the measured layer (by satellites) is due to Ozone depletion.
http://i23.photobucket.com/albums/b370/gatemaster99/stratoz.png
Santer et al 2003
At any rate, the stratosphere doesn’t tell you what happens with the rest of the system.
Secondarily, What exactly do you think that graph proves, other than that hundreds of years after milankovitch cycles initiate warming CO2 amplifies it?
Well Simon Evans, it doesn’t take long to discover that you do not attempt to discuss things, only push your propaganda. Sorry I wasted my time and Lucia’s blog space.
Bugs,
I notice there is a discussion about Stratospheric cooling. One of the trinity that makes up the “Fingerprint.”
Is there new data out on the stratosphere?? The RSS graphs still show the Strat flat for 15 years! The two drops previous were both apparently step changes after Volcanoes?
What are we using to show stratospheric cooling??
bug:
In physics, if you choose to ignore what the data and theory say, we call that “scifi”.
Bugs appears to think we should use Star Trek to set future climate policy.
Carrick (Comment#22866) October 31st, 2009 at 12:20 am
In physics, if you choose to ignore what the data and theory say, we call that “scifiâ€.
Bugs appears to think we should use Star Trek to set future climate policy.
Don’t get you. There is research into how, not only is CO2 a problem as a GHG, but methane as well, which we are also contributing to. CO2 has been studied extensively, methane not so much.
Your response is too cryptic to make any sense.
Andrew_FL (Comment#22863) October 30th, 2009 at 11:32 pm
Bugs-first of all, your “fingerprint†is not a “fingerprint†at all. The vast majority of the stratospheric cooling in the measured layer (by satellites) is due to Ozone depletion.
http://i23.photobucket.com/alb…..tratoz.png
Santer et al 2003
At any rate, the stratosphere doesn’t tell you what happens with the rest of the system.
Secondarily, What exactly do you think that graph proves, other than that hundreds of years after milankovitch cycles initiate warming CO2 amplifies it?
That graph is not in Santer, so i have no idea what you are saying it means.
On a geological timescale, the climate does change rapidly between extremes that are limited by boundaries.
The stratospheric cooling is a fingerprint for AGW, other natural climate forcings such as solar would warm the stratosphere, not cool it.
hey folks,
http://www.examiner.com/x-9111-SF-Environmental-Policy-Examiner~y2009m10d30-Examinercoms-First-Annual-Survey-on-Global-Warming
take the survey. support lucia she gets mentioned.
Simon Evans (Comment#22762) October 29th, 2009 at 4:51 pm
Andrew,
No Certainty = No Policy.
Why does your country maintain military forces then, for example? Or why do you insure your house? Surely it is obvious that we generally consider it wise to develop policies without certainty? By all means question the risk analysis, but stating a “no certainty = no policy†mantra seems daft to me. There is never certainty in any scientific assessment, thus you would never have any policy informed by your understanding of such assessments.
Thank you for this simon. ANDREW, I’m sorry but I spent a fair numbers of years working as an operational analyst. That’s a fancy term for a “war gamer.” Every action we planned, every scenario we gamed, every tool we used was RIFE with uncertainty. can you say FOG OF WAR, I knew you could. Did you set your alarm clock for tommorrow? Are you CERTAIN it will go off? is it logically True that it will go off? Is the sentence–
I set my alarm clock, therefore it will go off— is that sentence logically true, or do you just hope it is? do you just hope it is true because everytime to date your clock has gone off? It is not certain that your clock will go off. a power outage, batteries dying, device malfunction, shit happens. Ever set two alarms?
why? We almost always act under uncertainty, except when doing logic.
Andrew_KY (Comment#22763) October 29th, 2009 at 4:59 pm
Simon,
It is certain that a strong military will be needed. There are many wars currently being fought, all over the world. It is certain that weather or criminals will damage houses. We see these in the news daily. I see these things with my own eyes.
Science is supposed to provide certainty where none was before. That’s what science is about. If it doesn’t provide certainty, then it ain’t science, it’s speculation.
Andrew
Andrew you need to go back to epistemology 101.
Lets start with a definition of CERTAINTY.
it is certain that 1+1 =2. That is I cannot imagine a world in which it isnt true
it is certain that “white swans are white”
It is not certain that an object will fall according to the law of gravity. That is, I can well imagine doing an experiment tommorrow and finding out that an object doesnt. It would be highly improbable. In fact so improbable that people may well question my result. BUT it is IN PRINCIPLE imagineable. That is,
there is no LOGICAL CONTRADICTION or MATHEMATICAL contradiction in the sentence “These experimental results contradict the law of gravity”
science is not certain. it merely works. not always, however.
Tom Fullers part of the examiner is down! (The rest is up.)
TomVonk–
I’m not sure I’d agree with you. If one were approaching all problems mathematically first, maybe. But, otherwise? No. I don’t think people designing heat transfer devices are better off thinking of steady state behavior that is not at equilibrium in terms of stable attractors or any term from non-linear dynamics.
Pseudo-equilibrium does contain the word “pseudo” to convey it is not equilibrium. But it does share the notion that you’ve reached some sort of stable region. Of course in the specific case of Bernard cells, you could disturb the equilibrium by stirring, turning the steady heat on and off etc. But you could disturb real equilibrium the exact same way. So this is not an argument about not using the word “equilibrium”.
The only real problem I can see with people using an idea like “pseudo-equilibrium”, is they inevitably drop the “pseudo” part during conversations, and some forget that “pseudo” is implied. But everyone in every field needs to use words, and they borrow the ones that seem to communicate best. “Stable attractor” does not convey the key feature a person designing any engineered device is concerned about.
But, yes, the use of pseudo-equilibrium can case problems when it’s used in places where it does not make sense. (This is true of most words.)
Well… I only say Benard cells in the specific case where Benard cells form. I used it as an example. 🙂
The key thing about this particular example is that engineers might (and in fact do) want to only worry about the average heat flux across any plane for the purpose of estimating heat loads. So, the attractor exists and averaging can make sense in a particular context.
steven mosher,
cer·tain·ty (sûrtn-t)
n. pl. cer·tain·ties
1. The fact, quality, or state of being certain: the certainty of death.
2. Something that is clearly established or assured: “On the field of battle there are no certainties” (Tom Clancy).
It is clearly established that people and nations conflict with each other. There is no evidence that it will ever be otherwise. That’s why people own guns, and nations have militiaries.
My alarm clock is certain go off if I set it correctly and it is in good working order. Only an unrecognized change to the process could prevent it from going off if all the steps in the process are followed. People use alarm clocks because all things being equal, they are certain to go off. This is why people use computers. Unless somebody changes something, or something breaks, computers will work the same way, with certainty.
Again you bring the imaginary into the equation in your comment. You Warmers have a real problem with wanting to use your imagination to defend yourselves, don’t you?
Andrew
Mosh say it ain’t true! You a warmer? I thought you were another luke-warmer. Oh well, I will try to read more carefully. Or is it remmeber more carefully. All this talk of defintions, I begin to conclude that if I continue reading these, I will be able to understand Mann’s defense on the Tiljander. Then truly I will be in Wonderland. 😉
John F. Pittman,
A Lukewarmer and a Warmer are the same thing, as far as I can see.
They both imagine Global Warming and they both want government “to do something” about it.
They are in the same state of Arrested Development. 😉
Andrew
Arrested Development = funny show, BTW. Cancelled b4 it’s time.
Andrew
stephen mosher:
See comment about mind too open/brain falling out and splatting on floor.
Then the comment about science advancing at the boundaries, not overthrowing the center.
For all practical purposes, certainty gets arrived at in science, just as for all practical purposes an RC-circuit eventual drains to zero charge.
Lucia
.
“So, the attractor exists and averaging can make sense in a particular context.”
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This is really the point . Particular .
Engineers , for good reasons , don’t design devices that go in chaotic regimes .
There is one exception which is turbulence .
But in this case they constrain themselves again to particular contexts where one has empirical rules and the Kolmogorov theory that holds more or less well at the spatial and dynamical scales they work on .
Quasi infinite number of degrees of freedom , isotropy , homogeneity and such . Etc .
Steady state is bread and butter of engineering .
Transitories are just that , transitories from one steady state to another .
But unpredictable brutal dynamical state changes and bifurcations must be avoided because the device is supposed to work in a stable or at least controllable way .
.
When I am discussing climate , I am not discussing a simple steady state stable system and even less a system in equilibrium .
I talk about an unstable out of equilibrium system that apparently has a fractal low dimensionnal attractor .
Then all the methods and analogies evoked above are of no help and there is no reason why one should suppose that they could be .
.
An example .
If the attractor (we are talking phase space) looks like that : O-O .
Then time averaging its dynamical states gives a state where the system (almost) never is . In other words this system is not ergodic . There is no pdf that can describe it .
I am not saying that the climate attractor looks like that because nobody knows how it looks .
But I am saying that if one doesn’t ask the question then one can average and suppose steady states untill the hell freezes over and make no progress .
Andrew_KY (Comment#22877) said ”They both imagine Global Warming and they both want government “to do something†about it.’ I am a luke warmer and do not want government to do something about it; because I don’t even know if there is something that needs doing, or that the doing would be effective.
So perhaps you need to redefine. 😉
Andy Krause (Comment#22831)
Oh, I’m sure that the author of the blog has plenty of brains. But he’s chosen to say something that is either ignorant or else…. what? Deliberately deceitful? Tell me, do you think that the IPCC, for example, are projecting a “runaway greenhouse scenario”? If you do, please point me to your evidence of that. Do you think that the GISS temperature record is evidence of a “runaway greenhouse scenario”? If you do, please explain.
kuhnkat (Comment#22864)
I made several points in response to your last post, which I would count as ‘discussing things’, but it’s actually true that I have no further interest in discussion with you, so by all means do avoid wasting any further space by addressing comments to me.
Bugs:
Obviously you have never had any stick time in a helicopter. If you let go of the collective, you will auger in and won’t bounce back. You show a graph of temperature fluctuations during very recent times (I’d hardly call that geologic time… more like a blink of an eye) that shows absolutely no evidence of a crash and burn. Rather, this graph only shows temperature variation within an ice age. That’s right, we are living in an Ice Age and people are worried about global warming! Look at the history of mammals: warming temps = increased populations and diversity! The horror…the horror…
Anyway, Mr. Bug’s example shows that temperatures stay confined to a limited range and bounces up and down: classic dynamic equilibrium or strange attractor attraction.
I hope Mr. Bug will prove me wrong by showing us a earth temperature plot that spans ice and warm epochs that goes off the chart and does NOT fluctuate about a mean.
Carrick (Comment#22879) October 31st, 2009 at 8:37 am
Yes of course for all PRACTICAL purposes. For most practical purposes one can consider space to be euclidean. I’m speaking philosophically, which is not about practical purposes..grin.
Hmm OT.. but the quine duhem position captures my position.
( wait this thread is all over the place )
from wikipedia:
The Duhem–Quine thesis (also called the Duhem–Quine problem) is that it is impossible to test a scientific hypothesis in isolation, because an empirical test of the hypothesis requires one or more background assumptions (also called auxiliary assumptions or auxiliary hypotheses). The hypothesis in question is by itself incapable of making predictions. Instead, the consequences of the hypothesis typically rest on background assumptions from which to derive predictions. This prevents a theory from becoming conclusively falsified through empirical means if the background assumptions are not proven (since background assumptions sometimes involve one or more scientific theories). For instance, to “disprove” the idea that the Earth is in motion, some people noted that birds did not get thrown off into the sky whenever they let go of a tree branch. That datum is no longer accepted as empirical evidence that the Earth is not moving because we have adopted a different background system of physics that allows us to make different predictions.
Although a bundle of theories (i.e. a theory and its background assumptions) as a whole can be tested against the empirical world and be falsified if it fails the test, the Duhem–Quine thesis says it is impossible to isolate a single hypothesis in the bundle. One solution to the dilemma thus facing scientists is that when we have rational reasons to accept the background assumptions as true (e.g. scientific theories via evidence) we will have rational—albeit nonconclusive—reasons for thinking that the theory tested is probably wrong if the empirical test fails.
Howard (Comment#22895) October 31st, 2009 at 12:51 pm
Bugs:
Obviously you have never had any stick time in a helicopter. If you let go of the collective, you will auger in and won’t bounce back. You show a graph of temperature fluctuations during very recent times (I’d hardly call that geologic time… more like a blink of an eye) that shows absolutely no evidence of a crash and burn. Rather, this graph only shows temperature variation within an ice age. That’s right, we are living in an Ice Age and people are worried about global warming! Look at the history of mammals: warming temps = increased populations and diversity! The horror…the horror…
Anyway, Mr. Bug’s example shows that temperatures stay confined to a limited range and bounces up and down: classic dynamic equilibrium or strange attractor attraction.
I was just going along with their very simple analogy. That is, does the climate tend to stabilise itself, or is it inherently unstable. AFAICT, in recent history it has been quite stable, but in the long term it oscillates between the boundaries imposed by the physical limits of the system. That is, the energy coming from the sun and the Milankovich cycles. It can’t get below a certain temperature, and it can’t get above another.
Bugs:
You will comment on anything, won’t you? Even when you don’t have a clue and after Howard has corrected you. You just keep blundering on demonstrating your lack of understanding. A helicopter is UNSTABLE.
Howard:
Thanks again for your brilliant analogy. I keep rolling it over in my mind and it fits like a glove. I don’t have any time in rotary wing, but I have a fair bit of fixed wing time and an aeronautical engineering background.
David Jay (Comment#22910) October 31st, 2009 at 8:08 pm
Bugs:
You will comment on anything, won’t you? Even when you don’t have a clue and after Howard has corrected you. You just keep blundering on demonstrating your lack of understanding. A helicopter is UNSTABLE.
Howard:
Are you that incapable of understanding a simple point, and get past the deficiencies of a simple analogy. In geological time, the climate is UNSTABLE. It swings from one extreme to the other.
“I am a luke warmer and do not want government to do something about it; because I don’t even know if there is something that needs doing, or that the doing would be effective. So perhaps you need to redefine. 😉 ”
Perhaps we do, John. We should ask Lucia since she apparently coined the term Lukewarmer and she certainly wants “to do something” about Global Warming.
Do Lukewarmers necessarily want “to do something” about Global Warming? or should we further define Lukewarmers into sub-categories of like Statist Lukewarmers, Cover-For-Our-Friends Lukewarmers, and Throw-A-Bone-To-Big Science-Lukewarmers? 🙂
Andrew
Andrew_KY–
Steven_mosher coined “lukewarmer”. Some lukewarmers want to do something; some don’t.
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