Roger Pielke Jr. posted a discussion of Yohe vs. Lomborg. Evidently, Yohe thinks Lomborg misconstrued his views; both Lomborg and Yohe. Both Yohe and Lomborg commented left comments at Roger’s blog.
So, I bet you think I’ll comment on whether or not anyone misconstrued anything? Wrong. I’m just still puzzling over the projection for global mean surface temperatures (GMST) which were evidently used by the Copenhagen Consensus. They curved lines below show their projections. Projections are relative to 2005, so all curves begin with 0C at 2005. The rate of increase for the first few decades of this century struck me as higher than the central tendency for projections I read in the AR4, which is 2C/century. So, I downloaded the figure and added some tangent lines:
So…. it would appear the economic analysis from the Copenhagen Consensus 2008 seems to be based on a projection that suggests the current rate of warming has an expected value of 4 C/century. (That is, of course, the “underlying rate”, and weather varies around that.)
In contrast, the AR4 is projects 2C/century for the expected value of the current rate:
Oddly, 4C/century doesn’t even fall inside the uncertainty intervals the IPCC communicated with their projections for the first few decades of this century.
I wonder if the Copenhagen Consensus 2008 did any computations to figure out the economic impacts if the IPCC projection for warming during the early part of the century are actually right. But…I’m feeling a bit under the weather today. So, I think I’ll defer diving into that question until later. . . .
Well, done. As usual.
I don’t think so. It looks like they just screwed up the graph. They use the IPCC’s scenarios for the 2020s decade earlier in the paper.
Boris– Where do you find they used the IPCC scenarios? They do discuss them ( example page 9 http://www.copenhagenconsensus.com/Admin/Public/DWSDownload.aspx?File=%2fFiles%2fFiler%2fCC08%2fPapers%2f0+Challenge+Papers%2fCP_Global_Warming_-_Yohe.pdf ). They also cite and discuss cite from other people’s studies that use the IPCC projections. (See oages 14-15 etc.)
But as far as I could tell, for their original new analysis, they used six new emissions scenarios. On page 17, they begin discussing their own work:
“Six emissions scenarios were constructed. . . ” Their analysis then uses the “MERGE” model and the “FUND” model. FUND (not a GCM, ) calculates the temperature path based on the emissions path. (See page 19 and the appendix.)
I think that temperature path is what they show in the 3.2 on page 23. It’s not an IPCC AR4 trajectory. It’s not an IPCC AR4 average. The figure is surrounded by narrative explaiing how they got it. So, I don’t think their main results (Figure 4.1) used a SRES and/or any of the results in the IPCC document.
Their new, original results, are based on the temperature trajectory predicted by their FUND model, which predicts temperatures are currently in the process of rising at a rate of 4 C/century!
They do note that at the 100 year mark their projection is near the middle of the A1 scenarios projection from the AR4.
But bear in mind: Economic analyses are very sensitive to when costs occur. So, the dramatic shifting of the warming forward in their model compared to the IPCC projections is likely to result in higher costs occurring sooner.So, the very rapid warming shifted to now rather than in the future would, in an economic analysis, would result in the calculation increasing the benefits of immeidiate mitigation in the “it’s not now” scenario.
So, there is a big problem with that analysis: The temperature is simply not currently rising at 4C/century. Even using Gavin’s uncertainty intervals for the uncertainty in 8 year trends, the GMST has not not rising at 4 C/century!
So, how are we to interpret that paper? As an interesting academic exercise?
#5246
I don’t think the graph is screwed up. Here’s the associated text:
Appears to be based on a 3.0oC sensitivity.
Those curves are… odd, to say the least. Eyeballing it, the 2005 to 2010 projections seem to be around 0.6 degrees C per decade, slowly decreasing to around 0.3 degrees C per decade by 2100.
The IPCC projections, on the other hand, sensibly use an S shaped curve roughly reflecting the mean SRES trajectory of GHG emissions (e.g. increasing till 2050, decreasing thereafter).
The IPCC curve has the classic hockey-stick shape that seems to be so popular. It appears to be made from spliced data, which can easily result in such a shape. Why did the temperature variability get so much smaller starting in approximately 1960? Different data sets spliced together?
Anyway, it seems like each group that makes a projection increases the slope. How do any of these groups maintain their credibility? If the 2C per century is false and too high, 4C is hardly worth considering.
Of course, this shouldn’t all be just a tempest in a teapot.
Julia has previously thoroughly convinced me that the last 7 to 10 year ‘flat’ in recorded global surface temperature is outside the 95% confidence interval for the +0.2ºC/decade trend predicted by the ensemble of IPCC GCMs.
But as she – and Joe Romm
http://climateprogress.org/2008/08/21/debunking-the-myth-global-warming
note, that does NOT mean that the TOTAL earth has ceased to warm in response to the steady increase in atmospheric CO2.
So, what might it mean?
As a result of increased warming – from whatever cause(s) – a number of positive feedbacks are ‘activated’ that induce further warming. These are incorporated in all the GCMs to try to mimic what happens on the real Earth.
If the contribution of one of these dropped NON-LINEARLY, at about the year 2000, in a way not ‘properly’ represented in the GCMs, the flat might be explained. Is there any candidate for this type of behavior?
Northern Hemisphere (NH) continental snow cover swings from a maximum in the winter to a minimum in the summer. The albedo associated with that snow cover regulary goes from a maximum in the winter to a minimum in the summer. Because NH-insolation is greatest in the summer, and because there is much more land mass in the NH, small changes in snow cover in the NH-summer have disproportionately large effects on global temperature. As temperatures have risen during the last 50 years, the extent of remaining continental snow cover in July has been steadily shrinking. But the most it can shrink is to zero! Therefore, as that point is approached, the summer contribution of albedo-positive-feedback must sharply drop, and any up-to-then ‘regular’ contribution to increase in temperature must also fairly abruptly ‘end’.
I’ve searched unsuccessfully for discussions of such a model. It’s fairly easy to test. If summer-time NH-snow-cover has essentially zeroed out since 2000, the record at the National Snow and Ice Data Center
http://nsidc.org/data/snow.html
should show it clearly. (So far, I’ve been unable to find my way to the appropriate files. But I’m sure Julia, and many readers of this blog will have no trouble checking it out.)
How could the GCMs have ‘missed’ this? Easily. Adjusting GCMs to properly account for positive feedbacks involves some ad hoc tweaking to try to appropriately balance the contributions of each feedback by fitting past climate to model output. And this balancing act was probably guided by the same intuitions among the various modelers, generating similar biases. If snow-albedo-feedback was given a bit too little weight, and other feedbacks, a bit too much, the described non-linearity could have been buried in noise in GCM outputs. And the net effect would be to somewhat over-estimate the long-term warming trend.
Bottom line: If the model I’ve propsed is near right, the ‘true’ warming trend is probably less than +0.2ºC/decade. But after the effects of the recent La Nina and the current Solar minimum ‘wear off’, will be found to be at least +0.1ºC/decade. We’ll still have to fairly quickly break our largest CO2-footprint addiction to coal, and avoid the larger footprints of tar-sands, shale-oil, as well as most corn-ethanol, palm-biodiesel – and deforestation must be halted. As Jim Hansen emphasizes, our oil and gas reserves probably will run out soon enough to save us from ruin. But we’ll have a LITTLE more time to transition to sustainable and renewable energy sources.
Sorry to stir the pot 😉
#5251
Len, that is not an unproductive way of “stirring the pot”. The last two NH winters have been snowy. (Maybe someone can plot up some data?) Perhaps without that snow (and high albedo) NH temp would have risen above the observed flat line? Gavin Schmidt tells us that 9/55 GISS ModelE runs exhibit an 8-yr negative GMT trend. If you were to remove runs where NH snow cover was lower than observed, perhaps the number would go to, say, 9/45 or 9/30? This justifies your concern that it matters how theory is compared to reality. Ignoring “small” differences between the two could have large consequences, esp. when you are talking about differences in the (+) feedbacks.
Assuming snow albedo is as important as you suggest, one wonders where the increased snow came from. Melting polar ice? Or just a natural variation in precipitation redistribution? Do GCMs produce polar albedo-caused oscillations in NHT/GMT? Is that what is happening with the 1990s uptick and the 2000s flatline?
All part of the question of whether the models are faithfully mimicking observations. And how one judges “faithful mimicry”. Seems to me the criteria for fit are all post-hoc cherry-picked.
Len–
Stirring the pot is the whole purpose of blogs! No need to apologize.
Am I Julia? Is there a Julia at Romm’s blog? (The link didn’t work.)
My test are mostly limited to the question of are the models off. Some are convinced, some are not. If they are off, the question of why is important. But, for now, I’m trying to address the questions of two groups of people: a) those who believe the models are still on track and that all we are seeing is a blip consistent with “weather noise” and b) those who are convinced that we can’t under any circumstances, test projections using “short” data sets.
Lucia
Two to three years ago most economists would have told you that their models showed that economic growth was fine and all was proceeding well and that’s how things would continue.
Out of the blue for most comes what we in the UK call the ‘credit crunch’.
The implication being that no matter how refined the economic models are, and they have a much longer pedigree than climate models, they are not that good at predicting the real life future. And long term economic predictions are actually no more than academic exercises.
So how do the climate models differ? If anything they are even more complex than economic models. Yet we, the general public, are told to put our trust in them and that they can be accurate, according to the IPCC, for the next 100 years. And based on this we have to make large adjustments to our economies and lifestyles.
Your sterling work has demonstrated the problems with IPCC projections, but I feel so frustrated that the palpable shortcomings of the models are not openly acknowledged by the climate science community.
(rant over)
In the description of the FUND model, the authors state:
This is a bit confusing, because they cite Ramaswamy et al. 2001, which is actually the IPCC TAR section on radiative forcing and climate change.
Still, the graph is poorly made and should show temperature rise accelerating and not decelerating.
Boris–
I’m sill not seeing how you can be sure the graph is screwed up. That paragraph describes some features about the constitutive relations in the Fund model. But, you also need to know how the gases build up to get the shape of the tempeature curve. It appears the get the rate at which ghg’s are added to the atmosphere from the MERGE model.
Still, you could be correct and the graph could be screwed up. If so, one might hope they’d fix it so readers could have a clue what they really assumed when doing their analysis!
Lucia:
I must apologize for a “senior moment”. I don’t know any “Julia”!
The URL is http://climateprogress.org/2008/08/21/debunking-the-myth-global-warming-stopped-in-1998/
Len
The massive quantity of hubris apparent in the economic discussion at Pielke, Jr was a real eye opener. Economists can’t accurately predict the impact of tax or regulatory changes. Assessing the costs and benefits of
“global warming” 100 years from now is beyond silly. I hope they got paid well.
And I feel certain we will all be paying for such exercises for a long time.
“The radiative forcing of carbon dioxide, methane, nitrous oxide, sulphur hexafluoride and sulphur aerosols is determined based on Ramaswamy et al. (2001). The global mean temperature T is governed by a geometric build-up to its equilibrium (determined by the radiative forcing RF), with a half-life of 50 years. In the base case, the global mean temperature rises in equilibrium by 2.5°C for a doubling of carbon dioxide equivalents.”
I’m not sure how they get to 2.5C for 2xCO2 without making assumptions about feedback. You certainly can’t get it from the raw forcing numbers. Are feedback assumptions included in the FUND model?
I can see how they might get a decelerating trend by considering the logarithmic effect of CO2 doubling.
What I find insulting is that people like Yohe seem to think everything on earth should carry a price tag including the release of carbon. They seem to be bothered by the idea that someone can gain a benefit without paying a price in the form of a tax to be paid to a government. I suppose that they will want to tax rain and sunshine next. And why not tax breathing. It does, after all, release CO2. This seems to feed into the idea that everything is owned by the government, dispersed by the government, and taxed by the government. They seem to have no issue at all with the exercise of compulsion in the form of economic blackmail. They talk about it as though it were a virtue. Obviously human freedom and human choice play no role in their socialist model. I find this obnoxious and arrogant attitude to be a common element for most warmers. Indeed, the prospect of having AGW to use as a tool for implementing herd philosophies seems to delight them. The suggestion of potential solutions to their exaggerated problems that do not include the increase of socialist control over our lives are always rejected by them. For example, if carbon is their big concern, then why not replace carbon based power plants with nuclear plants. Since there is no agenda based power gain for them from such a solution they never give it consideration.
Len–
I thought I must be Julia! Don’t worry about it; people have called me lots of things. 😉
Sure, in principle, the ocean may have warmed since 2001, in which case, the earth may be warming even though the surface temperature has been flat or negative.
Everyone wants me to look at ocean heat content in recent years. But first I have to find a good, easily accessible data set for temperatures up to “now”– not just temperatures up to 2004. When Josh has Argo data up for the public, I’ll be adding that to tests. 🙂
“I’m not sure how they get to 2.5C for 2xCO2 without making assumptions about feedback.”
Of course feedbacks are included, but note that 2.5C is on the low side of model and empirical sensitivity estimates.
And Hansen is now promoting nuclear, specifically the Integral Fast Reactor. I don’t know much about this 4th generation technology, but if the details are accurate it will allay many fears of nuclear power that citizens have.
Boris–
Sure, 2.5C for 2xCO2 is on the low side of the IPCC range. So, to get the shape they have with the current 4C/century, they must have parameters that either prevent heat transfer to the ocean, or that transferred heat to the ocean already. (Either would make it not act like a heat sink now. To speculate further, we’d have to see the shape of the graph since the 50s or so.)
But, that graph, which supposedly was used to estimate the amount of harm due to warming does not match the trajectories in the IPCC document. Worse, the fast rise now would, in an economic analysis, tend to result in large costs now rather than later, and so make the calculated present value of any damage (or benefit large).
Maybe the graph is screwed up– but I would suspect that if it is, they would have caught that.
GREAT! Also, finally. The reluctance of those wishing for CO2 limits to specifically promote nuclear has been a huge stumbling block to action.
Every Evil Overlord should know all good propaganda campaigns should propagate fear of a threat. When the Evil Overlord creates a sense of urgency so that the fear becomes a crisis and people are gripped with anxiety, people are willing, even wanting, to be led toward a promised land where the threat is neutralized and fear is gone. So long as the goal appears to be getting closer but the threat remains, the Evil Overlord will maintain control.
Embrace your inner Evil Overlord.
Tilo Reber (Comment#5278)
“What I find insulting is that people like Yohe seem to think everything on earth should carry a price tag including the release of carbon.”
I don’t want to address carbon because the issue is not settled for me yet, and I also fear the same political forces that you mistrust.
But aside from all that, can I ask you to consider a general principle without specifically addressing carbon? Since you are participating on this site, I will take it as a given that you appreciate the power of natural laws. Further, based on your post, I suspect you share my frustration with those who seem to believe wishful thinking and/or propaganda campaigns empower us to overrule reality and natural laws. (which is why I don’t want anyone to apply the following thoughts specifically to carbon.)
Anyway, it is obvious to me that humans can use natural laws to our advantage even though we are not empowered to overrule them. (e.g. taking advantage of gravity/fluid mechanics with a hydro dam, without imaging we actually invented gravity, fluid behavior, etc.)
One of the natural laws is about human behavior — supply/demand, and we can use it to our advantage as well. Supply/demand tells us that human interactions will function with the least thievery and bloodshed and at best efficiency if we have a large quantity of willing & able traders. The very definition of ‘able’ means you have to actually own it. So, I hope you will consider the value of better definitions of property rights, including rights to clean air, clean water, etc., which have not been well defined within our traditional political/economic structures. That is, improving the definition of ownership of clean air and clean water is a way to use the power of supply/demand to our advantage if we correctly understand both the natural law itself and our own limitations.
Our current situation is: I can have a surveyor stake out my real estate, but no one can stake out my lifetime supply of clean air. The ownership does not exist in a defendable form; therefore even if I claim it, the reality is that no ownership exists unless we agree to share it.
If our society wants technology to advance so that clean air is protected we will be best served by employing the power of supply/demand (ie. wide spread incentives) to meet our shared goal. So, defining an ownership and assessing a cost is actually a very reasonable thing to do.
There are associated advantages as well. For example, pricing would allow us to define exactly what we believe is a reasonable degree of pollution when compared to our other needs. We could adjust the price over time to fit actual circumstances. Finally, to me, the most obvious reason for defining ownership and setting a price is I believe it would be best if the actual person who wants some pollution-producing good is the one who actually pays the otherwise society-wide cost.
jc,
Finally, to me, the most obvious reason for defining ownership and setting a price is I believe it would be best if the actual person who wants some pollution-producing good is the one who actually pays the otherwise society-wide cost.
There is a big flaw in your argument which is you assume everyone is starting from the same point. Those who are poor / relatively poor do not have the same choices, cannot make the non polluting decisions because they are beyond their means. So, as so often, those least able to pay and adapt will end up paying more.
“Of course feedbacks are included, but note that 2.5C is on the low side of model and empirical sensitivity estimates.”
You may be right about model estimates as a whole, Boris, but I know that there are models that go down as low as 1.7C. Which empirical sensitivity estimates are you refering to?
“And Hansen is now promoting nuclear, specifically the Integral Fast Reactor.”
Now you are shaking my faith in Hansen’s insanity Boris.
Dave Andrews (Comment#5301)
Please note that the sentence you object to immediately followed two sentences reading:
“For example, pricing would allow us to define exactly what we believe is a reasonable degree of pollution when compared to our other needs. We could adjust the price over time to fit actual circumstances.”
Yet, you have assumed an unaffordable price. Human reaction to supply/demand is not static. it changes with time and incentive. So, it is not a flaw in my logic. It is an extension of my earlier caveat:
“… use the power of supply/demand to our advantage if we correctly understand both the natural law itself and our own limitations.”
BTW, I truly appreciate your ongoing willingness to pay my bills and I don’t want you to read anything into any post that would discourage from continuing to do so. If you could be so good as to provide contact info . . .
jc,
One:
Humans do not react to supply and demand. Theories for supply and demand model human reactions.
When you say, “it would be best if the actual person who wants some pollution-producing good is the one who actually pays the otherwise society-wide cost,” you are assuming that the poor want to buy pollution producing goods. As if they have a choice. The poor, by definition, do not have extra money. They spend their money on necessities or go without. Necessities are by definition needed. They are what define the meaning of poverty. When you are poor, it is not the wanting but rather the need which drives a decision to buy.
In the theories of supply and demand, necessiities are considered inelastic. Which, again by definition, means that an increase in price will not decrease demand. Oh sure, sales of necessities might decrease some with the price increase, but that is because the poor will be forced to choose which necessities to go without.
Two:
In the United States, the ownership of the air is clearly defined. The air you breathe is the sovereignty of the States.
Raphael (Comment#5307)
Regarding your two points.
One- Chickens lay eggs that hatch and become chickens that lay eggs, etc. Similarly, humans react to S/D (usually through price changes), so S/D changes, so people react to S/D, etc. I suggest we agree not to belabor this point any further.
Two –
Agreed, in the U.S., ownership by the states represents the shared ownership concept I previously mentioned.
Regarding that form of ownership; SIPs have been around for years now so we can already see some of the effects. S/D applies, so some manufacturing has moved offshore, some prices are up, etc. But, some technology has improved, some of that technology actually improved efficiency which made some goods more affordable rather than less affordable, some formerly poor people got jobs in the new technological fields, etc. IMO, changes are seldom all good or all bad.
There are consequences to everything we do, and everything we don’t do. That is why it is imperative that we understand both natural laws and our own limitations.
And for the record, no, I am not assuming the poor want to buy pollution-producing goods. That assumption came from someone else. If someone is actually that concerned about the plight of the poor, there are plenty of available data regarding economic impacts/economic growth since the advent of SIPs to make their case. However, I feel like I have hijacked this thread enough already and don’t plan to discuss it further.
jc,
One: If you believe in evolution you would realize the first chicken was hatched from an egg that was laid by a non-chicken. 🙂
That being said, the first point was about the price elasticity of demand, a foundation of supply and demand theory. Supply and demand need not be as dynamic as you make it out to be as there can be no reaction to an increase in price.
Point two:
I have too many acronyms floating around in my head. SIP is a State Implementation Plan? Sure why not since you aren’t limitting the issue to carbon. But, I would think that whatever is being regulated needs to have a definable threat attached to it.
jc,
I didn’t assume an “unaffordable price”, just that, as Raphael also mentioned, the poor have relatively fewer choices available to them and if you adopt the process you described they will inevitably be spending a greater proportion of their income on the ‘pollution tax’.
Plus the wealthy, whilst they might be presumed to have higher polluting lifestyles will always be able to employ people to help them exploit loopholes in the system and devise avoidance schemes just as they now do with tax. Witness the admission by venture capitalists in the UK to a House of Commons committee last year, that despite earning millions, by milking the system they were actually paying tax at a rate lower than that paid by the cleaners in their offices!
jc says “One of the natural laws is about human behavior — supply/demand, and we can use it to our advantage as well. Supply/demand tells us that human interactions will function with the least thievery and bloodshed and at best efficiency if we have a large quantity of willing & able traders. The very definition of ‘able’ means you have to actually own it. So, I hope you will consider the value of better definitions of property rights, including rights to clean air, clean water, etc., which have not been well defined within our traditional political/economic structures. That is, improving the definition of ownership of clean air and clean water is a way to use the power of supply/demand to our advantage if we correctly understand both the natural law itself and our own limitations.”
The proper framing is capability and oppurtunity. As several of the posts in respone to this post by jc are indicating. In fact to stay on topic in this thread, I like the way Lucia is applying this “law” of nature. The IPCC and Copenhagen Consensus have shown and are known to have the oppurtunity. The question is the capability that they have responded to this oppurtunity.
Of all the comments, I find that the issue of benefits of climate change that, Yohe et al. present in their Figure 4.1, which is based on 3.5 C/century, the most interesting. At 2 C/century, it pays for us to do “business as usual” until about 2135. At the null or near null projection, it pays for us to do “business as usual” almost forever!!! In fact, at current temperature drops, it pays us to do even more “business as usual.” This is a coherent approach. If we were to be headed for another LIA, and CO2 does increase earth’s average temperature, Figure 4.1 would show that we would need to emit more CO2, and would recieve benefits as well.
Of course, it also indicates that all the yelling about we must do something now may be a bit misplaced considering current temperature trends.
John F. Pittman ,
You dare blaspheme the consensus? Figure 4.1 says only what it says! The consensus has spoken!! 🙂