Many bettors watched in shock and awe as the NH ice melted throughout June. We have now witnessed the lowest 30 day June Sea Ice record in the Jaxa record:
I’m almost afraid to see what July will bring us (but the script to bet on July will be up tomorrow.)
Wondering whose bet won the quatloos?
Hal!
[sockulator(../musings/wp-content/uploads/2009/09/UAHBets2.php?Observed=10.0305?Display=1?Metric=NH Ice?Units=C?cutOffMonth=6?cutOffDay=15?cutOffYear=2010?DateMetric=June, 2010?)sockulator]
Yet, looking at the detailed Jaxa chart, it is hard to see much cause for alarm. We are looking at the record since 2002, rather short in climate terms, usually one asks for a 30+ year series. Then, this year seems to have started out higher and moved lower, but the lines do cross each other quite frequently.
Betting may be problematic. But is there really anything to get excited about here? Any real sign that we are dealing with a phenomenon that is remarkable on a scale of say 100 years?
What will July bring us? From this alone, we won’t know. This isn’t a dataset where a naive look at one month’s numbers will give you much idea of what happens later in the year.
Re: carrot eater (Jul 5 10:29),
Agreed. But I suspect even with more information, July will be a bit of a crap shoot as far as betting goes.
Re: michel (Jul 5 10:14),
This graph doesn’t tell use much relative to 100 years. I picked JAXA because it’s rapidly available. Some of the longer data sets take longer to trickle out. Even with those, I don’t think we get a whole lot of precision over 100 years. But over a reasonable long amount of time, the trend does look like it’s downward.
I could swear I did place a bet (I have no idea what was my bet :)). It seems a monster ate it. Has this happened before?
michel, rest assured. Even if the Arctic becomes ice free, there will be no problem whatsoever. Nothing to worry about, all is well and will remain so forever. 😉
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July started off real slow. 2010 still has a lead, but it has been more than halved in less than a week.
“Betting may be problematic. But is there really anything to get excited about here? Any real sign that we are dealing with a phenomenon that is remarkable on a scale of say 100 years?”
There is something odd.
http://wattsupwiththat.com/2010/06/01/the-ice-who-came-in-from-the-cold/
The strong annual signal. I asked willis if this kind of change would ‘challenge’ his “null” hypothesis. he agreed it would.
Basically, we are seeing a change in the pattern of ice melt and recovery.. Its an assault on multiyear ice.
Finally, the question ” is there anything unusal in the past 100 years” is really the wrong question, as the term “unusual” is not readily quantifiable. The right question is
“what does the theory of AGW predict for Ice in the North.” it predicts less ice. So the data is consistent with the prediction.
Confirmation. Not proof. But confirmation. That doesnt make the theory right or precisely right or necessarily right. It means the theory predicts less ice and the observations are comporting with that prediction. How well are they fitting theory? That’s a different question. But the theory does predict less ice and you are seeing less ice.
Joe Bastardi (even as JAXA was setting record high extents back in April) predicted that the extent this season would go low, specifically between that of 2007/8. If he continues to get this right, further out, he’s down for a major ice increase through 2011-12.
So what about the South Pole? Is it coincidental that the south seems to mirror the north such that the global extent is pretty constant?
“Any real sign that we are dealing with a phenomenon that is remarkable on a scale of say 100 years?”
Per the NSIDC:
“The satellite record only dates back to 1979. However, scientists have used historical records of sea ice conditions to estimate sea ice extent before 1979.
To extend the satellite record back to 1953, scientists have used shipping records and ice charts from several countries in combination with satellite data. One such record, called the Hadley data set, indicates that Arctic sea ice has been declining since at least the mid-1950s. To view a graph derived from the Hadley data set, please see State of the Cryosphere: Sea Ice.
Before 1953, the historical record is less reliable. Shipping records go back to the 1700s, but only for limited areas and dates, and they do not always provide information about Arctic sea ice conditions. However, scientists do know that the Arctic was generally cooler up through the 1950s compared to recent years; the exception is a period during the 1930s and 1940s that was warmer than surrounding decades but still not as warm as recent years. Sea ice in the 1930s and 1940s was probably lower than it was during the 1950s. However, analysis of limited sea ice records from Russian ice charts indicates that while sea ice conditions were low, they were likely not as low as they have been during the 2000s. Plus, the trend in the 1930s and 1940s was both seasonal and regional in nature. The current decline touches all parts of the Arctic and affects all four seasons. ”
So we have observational evidence that the current conditions are unusual relative to the last 80 years, which would seem to pretty exactly address your “100 years” question.
The Arctic was substantially cooler than present conditions for several thousand years prior to the 20th century. So I don’t see any reason to think there were similar ice conditions then. Common sense as well as available observations, both directly of the ice and of the temperature record in the Arctic, suggest that the scientists who study the Arctic are right in describing current conditions as very unusual indeed.
Figure 2.16 shows results of Russian Arctic sea ice graphs.
http://alexeylyubushin.narod.ru/Climate_Changes_and_Fish_Productivity.pdf?
Since the authors show an 8 year lag between cyclical global temperatures and cyclical Arctic sea ice, melting is consistent with non-AGW explanations for some global warming.
very good sum up, Robert.
but let me start a preemptive strike, before the “sceptics” show up:
1. people who do not believe in countless thermometers should NOT believe in a story told about some vikings either. and there are green spots on greenland today!
2. the Antarctic is slightly different. it does NOT show a similar increase, but rather some pretty random changes, while the arctic shows a pretty obvious signal, as the scientists told us before it happened.
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i agree that the JAXA record is better for comparing short term events, than for a real indication of the state of the arctic.
cyrosphere sea ice area (while having shown a pretty significant anomaly recovery lately) is a much better hint at the state of the arctic ice.
http://arctic.atmos.uiuc.edu/cryosphere/IMAGES/sea.ice.anomaly.timeseries.jpg
the anomaly simply dipped into territory, that it never entered before 2007.
This is a test. Please ignore
Arctic ice extent is controlled by wind as well as temperature. The mean daily temperature north of the 80th parallels has remained slightly below average this year. The equinox is past and insolation is beginning to decline. The 2010 line looks like it will intersect the 2007 line shortly. IOW, multiple factors are at work and the pattern is just different this year.
Gary, you have been reading a lot of Steven Goddard Lately, haven t you?
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Steven is sticking to the completely false believe, that the only thing relevant for melting ice (apart from the winds, which he also likes a lot) are measured temperatures above 0°C.
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he simply is not willing to understand, that an awful lot of ice can melt, while a regional daily average temperature measured inside a stevenson screen remains below 0°C.
he also thinks that the warm winter anomalies don t have any influence on sea ice at all.
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in this bizarre world, he finally figured out that summer temperatures in 2007 were also below the average, not dissimilar to 2010.
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http://ocean.dmi.dk/arctic/meant80n.uk.php
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from his false assumption, he draws a false conclusion: it is the wind, and (nearly) only the wind.
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—————
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so can you explain to us, what made those multiple factors to be different this year?
Robert (Comment#47908)-“The Arctic was substantially cooler than present conditions for several thousand years prior to the 20th century.”
Several thousand years? Are you kidding me? Are you unfamiliar with the ice core data from Greenland? And how do you you define “several” anyway, because even if for some strange reason you think that the extend periods of time during the Holocene during which Greenland was warmer than it is presently were not Arctic wide, I could cite for you all sorts of references for past warm periods in the Arctic, some of them fairly long ago, some way to recently to allow your statement to be remotely true.
sod (Comment#47912)-“people who do not believe in countless thermometers should NOT believe in a story told about some vikings either. and there are green spots on greenland today!”
People who make snarky comments that ignore the vast evidence for a Medieval Warm Period in Greenland shouldn’t talk about people that don’t believe things that are true.
As if it’s just about the Vikings, right…
We’re finally getting to a point where the melting is going to have an impact on the final result. Just look at the JAXA graph. Just about now is when 2007 started falling off the cliff. It was a month or so later before 2008 took a dive. Look at the month 6 graph and try to predict where the minimum will be for previous years (try 2006).
“people who do not believe in countless thermometers”
I, for one, believe in thermometers, generally speaking.
What I don’t believe is analyses of thermometers presented by dubious sources, i.e. Warmers presenting analyses that conclude Global Warming.
It’s like members of congress voting themselves raises.
Andrew
it is funny, how the same people who talked about arctic sea ice “recovery” and “hitting normal” have changed their tune a little.
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http://wattsupwiththat.com/2010/03/31/arctic-sea-ice-about-to-hit-normal-what-will-the-news-say/
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anything that is above 2007 seems now to be in line with their claims!
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can anyone explain to these folks, that 2007 was NOT normal?!?
“Several thousand years? Are you kidding me?”
Those are the facts. Keep your hair on. 😉
For example:
Kaufman et al 2009
http://www.sciencemag.org/cgi/content/abstract/325/5945/1236
Axford et al (2009)
http://www.pnas.org/content/106/44/18443.full
You continue your bluster, scoring an own goal with this gem:
“if for some strange reason you think that the extend periods of time during the Holocene . . .”
So . . . evidently you don’t realize that the Holocene occupies a longer period of time than the last several thousand years. Ouch. That’s going to leave a mark (on your credibility.)
Last time we can say with confidence the Arctic was as warm as it is now was 5,500 years ago. Is that still the Holocene? Yep.
“I could cite for you all sorts of references . . .”
By all means. If you’re picking and choosing, peer-reviewed studies in high-impact journals, please.
I for one would not know quantitatively what is meant by ‘several thousand’, in the absence of other context. So let’s not bicker on that point; put some numbers to it and move on.
So, the Arctic is melting, but the Antarctic ain’t. Hardly a global event, or issit?
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http://icecap.us/images/uploads/JUNE22ANTARCTIC.jpg
http://arctic.atmos.uiuc.edu/cryosphere/IMAGES/global.daily.ice.area.withtrend.jpg
.
Tschüß
“I for one would not know quantitatively what is meant by ‘several thousand’, in the absence of other context.”
In which case the adult thing to do would be to ask, not launch into a arrogant rant demonstrating your own ignorance of the basics of paleoclimate.
We shouldn’t enable the “I don’t understand it/don’t like it” –> “Attack it as stupid and fake superior knowledge” reflex. It just encourages them.
Additional source: re Queen’s Island in the Canadian High Arctic:
“This period is the warmest for at least 1000 years and perhaps for several thousand years.”
http://www.sciencedirect.com/science?_ob=ArticleURL&_udi=B6VBC-4888CCV-3W&_user=10&_coverDate=12%2F31%2F1990&_rdoc=1&_fmt=high&_orig=search&_sort=d&_docanchor=&view=c&_searchStrId=1391414990&_rerunOrigin=scholar.google&_acct=C000050221&_version=1&_urlVersion=0&_userid=10&md5=c57fb7d8b8a07e0be2083d09481cdb03
I would say warmest in 2,000 years, high likelihood, warmer than 5,500 years ago, tossup, warmest in the last 20,000 years, likely not.
Antarctica’s losing ice too, Hoi, according to GRACE. As are the vast majority of glaciers in between the two polar regions. Looks global to me. 😉
Robert (Comment#47923)-You cite Kaufman et al, so I understand you to be saying, “several” thousand years is “two”. You cite Axford et al, which means you think that Baffin Island is the entire Arctic, okay. You know, that particular location hasn’t warmed significantly in the last 50 years, right? Okay then.
“So . . . evidently you don’t realize that the Holocene occupies a longer period of time than the last several thousand years.”
“Several”, um, there is very little of the Holocene I would consider more than several thousand years before the present. Perhaps the very earliest parts.
“Last time we can say with confidence the Arctic was as warm as it is now was 5,500 years ago. Is that still the Holocene? Yep.”
This is more than “several thousand years ago”? No way! Here I thought that several thousand years would be more than that.
“By all means. If you’re picking and choosing, peer-reviewed studies in high-impact journals, please.”
What is “High Impact”? We aren’t go to make any progress with you assuming that my understanding of these vague terms is that same as yours. For one thing, you assumed that I knew that your idea of several thousand years, is less than six thousand. I consider several thousand years to go back seven at least.
The following studies from various locations all North of 60 degrees latitude, indicate that you wouldn’t need to go more than a couple thousand years back to find a period as warm as or considerably warmer than the present, and many of them indicate you wouldn’t need to go back even that far-but they are clearly not in “high impact” journals:
Zabenskie, S. and Gajewski, K. 2007. Post-glacial climatic change on Boothia Peninsula, Nunavut, Canada. Quaternary Research 68: 261-270.
Linderholm, H.W. and Gunnarson, B.E. 2005. Summer temperature variability in central Scandinavia during the last 3600 years. Geografiska Annaler 87A: 231-241.
Johnsen, S.J., Dahl-Jensen, D., Gundestrup, N., Steffensen, J.P., Clausen, H.B., Miller, H., Masson-Delmotte, V., Sveinbjörnsdottir, A.E. and White, J. 2001. Oxygen isotope and palaeotemperature records from six Greenland ice-core stations: Camp Century, Dye-3, GRIP, GISP2, Renland and NorthGRIP. Journal of Quaternary Science 16: 299-307.
Kobashi, T., Severinghaus, J.P., Barnola, J.-M., Kawamura, K., Carter, T. and Nakaegawa, T. 2010. Persistent multi-decadal Greenland temperature fluctuation through the last millennium. Climatic Change 100: 733-756.
Rolland, N., Larocque, I., Francus, P., Pienitz, R. and Laperriere, L. 2009. Evidence for a warmer period during the 12th and 13th centuries AD from chironomid assemblages in Southampton Island, Nunavut, Canada. Quaternary Research 72: 27-37.
Axford, Y., Geirsdottir, A., Miller, G.H. and Langdon, P.G. 2009. Climate of the Little Ice Age and the past 2000 years in northeast Iceland inferred from chironomids and other lake sediment proxies. Journal of Paleolimnology 41: 7-24.
Weckstrom, J., Korhola, A., Erasto, P. and Holmstrom, L. 2006. Temperature patterns over the past eight centuries in Northern Fennoscandia inferred from sedimentary diatoms. Quaternary Research 66: 78-86.
Fortin, M.-C. and Gajewski, K. 2010. Holocene climate change and its effect on lake ecosystem production on Northern Victoria island, Canadian Arctic. Journal of Paleolimnology 43: 219-234.
Seppa, H. and Birks, H.J.B. 2002. Holocene climate reconstructions from the Fennoscandian tree-line area based on pollen data from Toskaljavri. Quaternary Research 57: 191-199.
Sicre, M.-A., Jacob, J., Ezat, U., Rousse, S., Kissel, C., Yiou, P., Eiriksson, J., Knudsen, K.L., Jansen, E. and Turon, J.-L. 2008. Decadal variability of sea surface temperatures off North Iceland over the last 2000 years. Earth and Planetary Science Letters 268: 137-142.
Jiang, H., Ren, J., Knudsen, K.L., Eiriksson, J. and Ran, L.-H. 2007. Summer sea-surface temperatures and climate events on the North Icelandic shelf through the last 3000 years. Chinese Science Bulletin 52: 789-796.
Mazepa, V.S. 2005. Stand density in the last millennium at the upper tree-line ecotone in the Polar Ural Mountains. Canadian Journal of Forest Research 35: 2082-2091.
Grudd, H. 2008. Tornetrask tree-ring width and density AD 500-2004: a test of climatic sensitivity and a new 1500-year reconstruction of north Fennoscandian summers. Climate Dynamics: 10.1007/s00382-0358-2.
Grudd, H., Briffa, K.R., Karlen, W., Bartholin, T.S., Jones, P.D. and Kromer, B. 2002. A 7400-year tree-ring chronology in northern Swedish Lapland: natural climatic variability expressed on annual to millennial timescales. The Holocene 12: 657-665.
Andersson, C., Risebrobakken, B., Jansen, E. and Dahl, S.O. 2003. Late Holocene surface ocean conditions of the Norwegian Sea (Voring Plateau). Paleoceanography 18: 10.1029/2001PA000654.
Sidorova, O.V., Vaganov, E.A., Naurzbaev, M.M., Shishov, V.V. and Hughes, M.K. 2007. Regional features of the radial growth of larch in North Central Siberia according to millennial tree-ring chronologies. Russian Journal of Ecology 38: 90-93.
Hu, F.S., Ito, E., Brown, T.A., Curry, B.B. and Engstrom, D.R. 2001. Pronounced climatic variations in Alaska during the last two millennia. Proceedings of the National Academy of Sciences, USA 98: 10,552-10,556.
Lassen, S.J., Kuijpers, A., Kunzendorf, H., Hoffmann-Wieck, G., Mikkelsen, N. and Konradi, P. 2004. Late-Holocene Atlantic bottom-water variability in Igaliku Fjord, South Greenland, reconstructed from foraminifera faunas. The Holocene 14: 165-171.
Sundqvist, H.S., Holmgren, K., Moberg, A., Spotl, C. and Mangini, A. 2010. Stable isotopes in a stalagmite from NW Sweden document environmental changes over the past 4000 years. Boreas 39: 77-86.
Podritske, B. and Gajewski, K. 2007. Diatom community response to multiple scales of Holocene climate variability in a small lake on Victoria Island, NWT, Canada. Quaternary Science Reviews 26: 3179-3196.
Geirsdottir, A., Miller, G.H., Thordarson, T. and Olafsdottir, K.B. 2009. A 2000-year record of climate variations reconstructed from Haukadalsvatn, West Iceland. Journal of Paleolimnology 41: 95-115.
Haltia-Hovi, E., Saarinen, T. and Kukkonen, M. 2007. A 2000-year record of solar forcing on varved lake sediment in eastern Finland. Quaternary Science Reviews 26: 678-689.
Jennings, A.E. and Weiner, N.J. 1996. Environmental change in eastern Greenland during the last 1300 years: evidence from foraminifera and lithofacies in Nansen Fjord, 68°N. The Holocene 6: 179-191.
EirÃksson, J., Knudsen, K.L., Haflidason, H. and Heinemeier, J. 2000. Chronology of late Holocene climatic events in the northern North Atlantic based on AMS 14C dates and tephra markers from the volcano Hekla, Iceland. Journal of Quaternary Science 15: 573-580.
MacDonald, G.M., Kremenetski, K.V. and Beilman, D.W. 2008. Climate change and the northern Russian treeline zone. Philosophical Transactions of the Royal Society B 363: 2285-2299.
Kaplan, M.R., Wolfe, A.P. and Miller, G.H. 2002. Holocene environmental variability in southern Greenland inferred from lake sediments. Quaternary Research 58: 149-159.
Wagner, B. and Melles, M. 2001. A Holocene seabird record from Raffles So sediments, East Greenland, in response to climatic and oceanic changes. Boreas 30: 228-239.
Cremer, H., Wagner, B., Melles, M. and Hubberten, H.-W. 2001. The postglacial environmental development of Raffles So, East Greenland: Inferences from a 10,000-year diatom record. Journal of Paleolimnology 26: 67-87.
Matul, A.G., Khusid, T.A., Mukhina, V.V., Chekhovskaya, M.P. and Safarova, S.A. 2007. Recent and late Holocene environments on the southeastern shelf of the Laptev Sea as inferred from microfossil data. Oceanology 47: 80-90.
Wiles, G.C., Barclay, D.J., Calkin, P.E. and Lowell, T.V. 2008. Century to millennial-scale temperature variations for the last two thousand years indicated from glacial geologic records of Southern Alaska. Global and Planetary Change 60: 115-125.
Vinther, B.M., Jones, P.D., Briffa, K.R., Clausen, H.B., Andersen, K.K., Dahl-Jensen, D. and Johnsen, S.J. 2010. Climatic signals in multiple highly resolved stable isotope records from Greenland. Quaternary Science Reviews 29: 522-538.
Kullman, L. 1998. Tree-limits and montane forests in the Swedish Scandes: Sensitive biomonitors of climate change and variability. Ambio 27: 312-321.
Barclay, D.J., Wiles, G.C. and Calkin, P.E. 2009. Tree-ring crossdates for a first millennium AD advance of Tebenkof Glacier, southern Alaska. Quaternary Research 71: 22-26.
By the way, the multiproxy methods used in studies like Kaufman’s are the same as those used by Mann and the like. I’m sure you will tell me it’s all a crazy conspiracy theory, but if you want to insist that those methods are correct, and I know you will, then there is no point in arguing that. Still however, we agree that the Arctic was as warm as today about five thousand and a half years ago, you just don’t think that any time in between then and now it was comparably warm. By my definition of “several thousand years” (and my definition is the fair way to judge what I meant, mister “you have credibility because you learn several was more than a few and less than a dozen, but not that it clearly no more than four! Everyone knows that!” (honestly, I should scold my grade school teachers thanks for the heads up))
EDIT: “In which case the adult thing to do would be to ask, not launch into a arrogant rant demonstrating your own ignorance of the basics of paleoclimate.”
Hm, what’s in an earlier post of mine?
“And how do you you define “several†anyway”
Oh, golly, I asked!
“Robert (Comment#47923)-You cite Kaufman et al, so I understand you to be saying, “several†thousand years is “twoâ€. You cite Axford et al, which means you think that Baffin Island is the entire Arctic, okay.”
Well, clearly you don’t understand me, any more than you understand the duration of the Holocene. I’m afraid I can’t take responsibility for your lack of reading comprehension.
If you can’t read grown-up articles and make reasonable inferences, there’s no point playing dueling posts with you.
Please be prepared to swear or affirm that you have read (cover to cover) and to the best of your ability, understood, a basic textbook on paleoclimatology. Then we’ll talk again.
“Oh, golly, I asked!”
When you open with whiny, conceited nonsense and distract the reader with the mind-blowing ignorance of not knowing what the Holocene is, the points you make further down are apt to get lost.
Robert (Comment#47929)-Maybe you could, I don’t know, learn to actually read through my posts? Or is that too hard for someone so sure he is more intelligent than me!
I think that you will find that I do indeed know the duration of the Holocene, an I think you will find that most of the Holocene meets my qualifications for being within several thousand years ago. That it does not meet your criteria, is interesting, since it suggest that we don’t agree on what “several” is. But your increased hostility is totally unjustified. You are trying way to hard to get mad at me for having the temerity to disagree with a statement that does not comport with the literature I am familiar with. The origin of our disagreement is something so mundane as what “several” means quantitatively, and you’ve got to get pissed off about it! Jeez man, seriously…
lucia (Comment#47896) July 5th, 2010 at 11:27 am
Re: carrot eater (Jul 5 10:29),
This isn’t a dataset where a naive look at one month’s numbers will give you much idea of what happens later in the year.
Agreed. But I suspect even with more information, July will be a bit of a crap shoot as far as betting goes.
Re: michel (Jul 5 10:14),
This graph doesn’t tell use much relative to 100 years. I picked JAXA because it’s rapidly available. Some of the longer data sets take longer to trickle out. Even with those, I don’t think we get a whole lot of precision over 100 years. But over a reasonable long amount of time, the trend does look like it’s downward.
====
Yes, but forecasting month-to-month changes, as you imply, is a crap shoot. Maybe I’ll try anyway, since I can’t lose real money.
Making forecasts and criticizing forecasts seem equally risky.
What will July bring?
Well June was dominated by high pressure and low pressure seems to have taken over in a big way and GFS models predict this to continue for the next 7 days. If that is anything to go by July will be much cloudier and cooler than June was.
On the seasonal cycle, consider the possibility that it is due to the geography of the Arctic. What if the ice edge is moving X kilometres north each year all year round? In summer the ice edge forms a wide arc within the Arctic ocean, so moving it X kilometres further north will melt a lot of ice. In winter the ice edge forms a narrow arc in the North Pacific; there is a wider arc in the Atlantic, but due to the warming waters of the Atlantic currents there is a sharp temperature gradient between the Arctic basin and the far north Atlantic, so the ice edge moves little between summer and winter.
The seasonal cycle may be partly due to ice growth/shrinkage being more restricted in winter than it is during summer. However also note that the winter ice edge in the Bering Straight is almost unchanged over the last 30 years, so whether there is some multi-decade trend towards cooling in these waters to offset the warming, or whether its a natural boundary between much warmer Pacific waters and Arctic……
If you look closely at CT tale of the tape there is a hint of a reverse of the current cycle in the 80s, with generally higher anomalies in summer/autumn, and closer to average during winter/spring.
However 2007 does seem a little bit of a step change in seasonal behaviour, and at the same time the Antarctic seems to have gone through a step change in the seasonal cycle of its own. The Antarctic seems to have a much stronger growth of ice towards maximum, although the maximum, minimum, and melt to minimum seem to be relatively unchanged.
Connection or coincidence?
I could tell you guys were going to bicker needlessly over ‘several’, and then you did anyway. Come on, now.
carrot eater (Comment#47940)-I’m ready to move on. Sorry for proving your instincts about our combativeness correct.
“I could tell you guys were going to bicker needlessly over ‘several’, and then you did anyway. Come on, now.”
There’s no point in bickering, period. If somebody’s not willing to have an honest conversation about the evidence, whether because they don’t understand it or because they are determined to be disingenuous, there’s no point in continuing. Especially people like Andrew who try to pass off their ignorance/dishonesty with bluff and bluster.
Robert, please. Andrew’s moving on, you’d do well to move on as well. It was a not terribly interesting dispute, made worse by machismo.
If you think the references you gave are sufficient to explain what you meant by the last several thousand years thing, then leave it at that. If you think more explanation is necessary in light of whatever confusion has come up, then do that. But the bickering gets in the way of either option.
“Robert, please. Andrew’s moving on, you’d do well to move on as well.”
Carrot, I fail to understand why you are continuing the discussion in the hopes of stopping it.
What Andrew calls his “combativeness” is childish obnoxiousness made worse by a demonstrable lack of understanding of the basic science. This is not the first time he’s responded to science he doesn’t like with bluster and ridicule. He’s dishonest — as demonstrated, for example, that long list copied without acknowledgment (or, one expects, understanding) from Fred “asbestos is good for you” Singer’s delusive rants.
For those reasons, I’m not going to engage in a back-and-forth with him — on this or any related subject — unless he chooses to learn some science — and preferably some adult manners as well (although I would concede that rude people are more bearable when they come bearing strong arguments — which never seems to be the case with Andrew). All of which I said above. So why are you still dragging this discussion out? Goodnight.
Actually, I noticed several studies were not cited but Polyakov et al (2003) seems to address Roberts position:
“The composite temperature record shows that since 1875 the Arctic has warmed by 1.2°C, so that over the entire record the warming trend was 0.094°C decade−1, with stronger spring- and wintertime warming. The Arctic temperature trend for the twentieth century (0.05°C decade−1) was close to the Northern Hemispheric trend (0.06°C decade−1). The oscillatory behavior of Arctic trends results from incomplete sampling of the large-amplitude LFO. For example, the Arctic temperature was higher in the 1930s–40s than in recent decades, and hence a trend calculated for the period 1920 to the present actually shows cooling. Enhancement of computed trends in recent decades can be partially attributed to the current positive LFO phase.”
Clearly states that it was warmer earlier in the 20th century in the Arctic than it is now. There are similar studies that show the same thing for the Antarctic. The warmest period for both poles were the 1930-40s, draw you own conclusions.
“He’s dishonest — as demonstrated, for example, that long list copied without acknowledgment (or, one expects, understanding) from Fred “asbestos is good for you†Singer’s delusive rants.”
Not to get back on this subject, but one can hardly be dishonest if one does not even understand that they are wrong. And BTW, I don’t know why exactly you think I got my list of references from Fred Singer, but that’s not where I got it from. I am saying this merely for the record, whether you believe me when I say that is not where I got them from, does matter to me, because I know it isn’t. And you are not a liar, even though you called me one, you are just wrong about where the references came to me from. Cheers. 🙂
PS-I’m being nice now, so lets get along, okay?
Oh, and yes, I am still moving on, I just don’t think I should be expected to do nothing about me being called a liar.
But, in point of fact, whatever Robert may say next, I’ll never see, because in the spirit of guaranteeing that I will move on, I hereby ban myself from this thread. Good Night to you all! I wish you all the best.
Lucia,
I’d say a much more interesting contest would be to estimate how much ice was around in 1944 when the St Roche crossed the arctic via the northern route of the Northwest Passage when the ice was at very similar levels as today.
http://hnsa.org/ships/stroch.htm
damned, i missed to include the St. Roche in my post above!
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it took the ship 3 years to make the passage. ships today just sail through it.
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this could have been an artefact, created by modern satellite navigation and pictures, allowing ships to find hidden passages. but that is not what is happening. the passages were wide open.
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we simply do not have accurate reports of similar events in the past. fact.
damned, i missed to include the St. Roche in my post above!
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it took the ship 3 years to make the passage. ships today just sail through it.
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this could have been an artefact, created by modern satellite navigation and pictures, allowing ships to find hidden passages. but that is not what is happening. the passages were wide open.
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we simply do not have accurate reports of similar events in the past. fact.
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ps: trouble with posting errors is back?!?
Neven, there is a real question which reasonable well informed people can raise in good faith, and to which the answer is not obvious. It is whether the spaghetti graph (and the other evidence) gives reason to think that we are one, two or three standard deviations away from the mean. And if so, whether the distributions we are dealing with are long tailed or normal.
When you look at the charts from the satellite era, its not obvious. In particular also its not obvious that this year is significantly different from previous years.
Now, we may nevertheless, some of us, find those graphs alarming. The difficulty is that if we act in public policy matters on the basis of feelings of alarm, we are liable to spend all our resources on imaginary threats, while not dealing with real ones.
Steven Mosher: surely what we need is not ‘consistent with’. Surely what we need is a natural experiment where some hypotheses can be falsified? The evidence seems to be consistent with the truth AGW, but it also consistent with its falsity. My question is, whether its consistent with the null hypothesis: that there is nothing much to explain other than random variation about a mean.
@Robert: “Antarctica’s losing ice too, Hoi, according to GRACE. As are the vast majority of glaciers in between the two polar regions. Looks global to me. ;)”
Really? Did you looked at the links? Wait, I have another one for you:
http://arctic.atmos.uiuc.edu/cryosphere/IMAGES/seaice.recent.antarctic.png
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You might inform the authorities that they are wrong.
Steven Mosher: surely what we need is not ‘consistent with’. Surely what we need is a natural experiment where some hypotheses can be falsified? The evidence seems to be consistent with the truth AGW, but it also consistent with its falsity. My question is, whether its consistent with the null hypothesis: that there is nothing much to explain other than random variation about a mean.”
1. by consistent with I mean ‘confirm’. evidence either confirms or disconfirms. There is no verification or falsification. In the logical sense of the word. Theories must be falsifiable in principle. In practice theories are generally modified rather than falsified. or abandoned.
Your notion of a null is rather quaint.
Andrew
“And BTW, I don’t know why exactly you think I got my list of references from Fred Singer, but that’s not where I got it from. I am saying this merely for the record, whether you believe me when I say that is not where I got them from, does matter to me, because I know it isn’t. ”
It is an interesting circumstance when someone accuses you of lying and you know they are wrong.
Classic blog thread drift. The original statement was this: (Robert (Comment#47908) July 5th, 2010 at 1:54 pm):
A 3000-year cooler period would plainly be sufficient for this to be true (in fact, in my native English, 2000 years would be). He didn’t claim, nor was he attempting to claim, the whole Holocene.
Warmistas are going to get one hell of shock soon re NH ice
steven mosher to michel:
“Your notion of a null is rather quaint.”
—-
I am puzzled by the lack of specificity in references to natural climate variability as a null hypothesis. While I have little formal training in statistics, my understanding is a null can be statistically tested and rejected to verify an alternative hypothesis, and in order to be tested the two must be numerically exact and mutually exclusive. It seems to me these requirements are not met by simply stating that the null is natural climate change and the alternative hypothesis is anthropogenic climate change. Yet, natural climate variability is frequently called the null. Is that a misunderstanding of the null ?
Relax,
you sound like one of them panicked doom&gloom alarmists.
July rates show a bit of a slowdown. Antarctic gains are almost offetting the Arctic losses.
Too much coffee?
Max_OK–
Verify is too strong, but you probably get that.
In addition to being mutually exclusive, they must encompass all possible true statements.
So, you have to make the hypotheses something like Null: “X is true” vs. Alternate: “X is not true”.
So, it could be “It’s natural” vs. “It’s not natural”. With respect to the logic of a statistical test, for excluding the “null” to come close to verifying the alternate, the two hypotheses can’t be Null:”It’s natural.” vs. Alternate: “It’s CO2”, because that could leave, say, black carbon, land use etc.
You can set up a test where what you expect under natural climate variability is the null. Then you can test whether observations are consistent with what you expect under natural climate variability.
Natural climate variability doesn’t have to be the null. You can pick a projection based on the assumption that AGW is true as a null.
The comments referring to the Antarctic Sea Ice extent offsetting concern about the Arctic Sea Ice are akin to saying do not worry about the US economy China is doing good. Lucia is correct to not refer to the other hemisphere and is right to be concerned. The June loss is not a surprise to snow melt observers, since the March-May period led to by far the greatest snow cover melt off in the last 44 years in North America and the Northern Hemisphere. Particularly the low May snow cover, which is mostly circum-Arctic cover is a good indicator of the early season melt condition for the near shore Arctic sea ice. The sea ice record is not as long term but some of the adjacent glaciers to the Arctic are showing the impacts of the unusual melt conditions of the last decade, ie Petermann Glacier
Joe Bastardi says:
http://www.accuweather.com/world-bastardi-europe-blog.asp?partner=accuweather
“And for the ministers of propaganda on this matter that don’t understand how this works, you will see NEXT SUMMER has the highest amount of sea ice since the early part of last decade. Sad to say the ice will rebuild… two steps forward one step back.”
I’ve been following Joe for quite some time, and his longer term forecasts have been pretty damn good.
“The theory suggests we will have less ice”. Hey I have a theory, I live on the east coast and it’s summer. My theory is that we will experience warmer temperature in the summer. Oh boy, look my theory is coming true! Lucia I’m just wondering, what is supposed to happen with global warming? Is a giant piece of an ice cap going to rip off and the earth is going to lose it’s magnetic field or something? Honestly, what does anybody think is going to happen? There isn’t going to be some giant event, probably what will happen is theres going to be an earthquake and no matter what it was global goring.
Re: sod #47971 (Jul 6 00:47) wrote –
Well, yes and no to the “3 years” part. From MikeC’s link in #47966 –
Mauri–
Are you going to wager any Quatloos? It would be fun to have someone who watches ice in a professional vein betting — even with these very noisy bets!
Shooshmoon
Mostly, with respect to the arctic, it’s supposed to get warmer and we expect the amount of NH sea ice to decline over time. Of course, we still expect to see an annual cycle– but June averages will decline relative to June averages, July relative to July and so on. I haven’t done any computations to figure out the rate of ice decline projected by models– Mauri might know.
I’m unaware of anyone predicting the earth will lose it’s magnetic field, but the world is large. You never know. (There is a guy out there with a web page that discusses extra-terrestrials and climate change. So, when I say you never know, I really mean you never know!)
Nick Barnes:
It’s still a rather cheeky claim, regardless of how you cut it.
What we know right now is that warming has had a progressive influence on arctic ice, and it may even be the case that this rate of warming and it’s impact on arctic climate is “unprecedented” in the last ___ thousands of years (insert your favorite number).
But what people also realize is the 2007 minimum probably wasn’t directly related to the “unprecedented” warming,which gives so far a pretty monotonic decrease in arctic sea ice which is sitting on top of a much larger annual variation in ice minimum, which is associated instead with wind and ocean current patterns.
If the warming continues unabated (and it most likely will), in a few generations, we will consistently see an ice-free arctic sea in summer. That will almost certainly be unique since the end of the last ice age at least. (There’s evidence that the previous interglacial period was warmer at it’s peak, we may have experienced a similar summer ice-free arctic.)
I don’t understand the concentration on air temperature and winds. Fluctuations in ocean currents are far more important. The AMO index shifted to positive mode in about 1995. If you plot Arctic ice anomaly on a CUSUM chart, you get a significant change in trend about 1995. The AMO can be thought of as an indicator of net heat transfer from South to North. When it’s positive, the Arctic is warmer and the Antarctic is colder and vice versa when it’s negative. Bastardi is betting that the AMO is headed into negative territory and that this summer is the last hurrah, abetted by an El Nino. That is not an unreasonable position.
We’re in an inter-glacial period. Is anyone really surprised that the Antarctic ice cap is losing mass? It would be losing mass whether humans existed or not. We don’t have anything like good enough data to say that the current loss rate has been increased significantly by human activity.
DeWitt Payne:
Here’s a reference.
Max_OK
I’ve criticized Willis’ notion of a Null ( in comments he may not have read on posts at WUWT) on two grounds.
1. not clearly stated in numerical terms.
2. missing the point about failure to reject.
on point 2 we may, for example, see a cooling that is WITHIN “normal variation” which can be explained without appealing to “natural variation”. Namely, the cooling after a volcano. under a Willis like Null, such an event would be ‘nothing to explain’. but clearly, we can explain these episodes that fall within the bounds of “natural” variation. The position that the only thing that requires explanation is outliers, reduces all science to abduction.
That’s it. That’s probably the way to do it. I was just thinking this morning that just about the only kind of natural disaster that has not been linked to global warming yet is the probability of the Earth being hit by a giant asteroid, and I was trying to figure out how one might go about making a connection. Now all we need to do is figure out (1) how global warming will affect the magnetic field of the Earth, and (2) how this will result in a greater pull on nearby iron asteroids. With a little imagination, it should be possible to come up with something good enough for the evening news, or at least the Proceedings of the National Academy of Sciences…
How many is several? technically, more than 1. But, as a writing instructor I would blue pencil Nick barnes or anybody else who wrote “several” and MEANT 2. Usage probably leans toward ‘several’ meaning 3-10
if you believe this sort of crap
http://wiki.answers.com/Q/How_many_is_several
a couple, a handfull, more than a handful,several.
Being from Michigan, we use this locution
“a couple three”
http://www.urbandictionary.com/define.php?term=a%20couple%20three
I had a couple of thoughts. He had several. who had more?
For those following arctic temperatures (and I don’t mean only those above 80N), the crash of the Arctic sea ice in June is NOT surprising. This spring has been very warm in the Arctic regions. That doesn’t mean much in March and April when the temperatures are still below freezing. But once the “normal” temperatures go above freezing, a positive anomaly of 5 Celcius is significant. So the crash that we are seeing is primarily first year ice (Hudson Bay, Barents Sea etc etc). I predict that the rate of Arctic sea ice decline will slow significantly over the next month as multiyear ice comes into play and that we will have a minimum that is more than 2008 but less than 2009.
carrick,
I think people get wrong footed when they try to argue that the “unprecedented” loss of ice is somehow proof of AGW. It’s not. It’s rather a consequence of AGW. We know AGW is true because of the fundamental physics of radiative transfer. We know that adding C02 or other GHGs will warm the planet. We know that heat will get shuffled poleward. A shrinking artic ice measure is consistent with the increase in temperatures, but it doesnt play any significant role in the proof chain of AGW. Primarly because the melt is driven by a multitude of factors: temperature, current, clouds,wind, soot, salinity. So that pointing to past ice measures is really beside the point. We may have had substantially less ice in the past for entirely different reasons. So, the whole argument of un precendented or not is really a non argument.
Steven, i don t understand your argument above at all.
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on WuWt, Steven Goddard has written a series of 12 posts, about the arctic sea ice “recovery” that we will see this September. plenty of folks there disagree with the idea, that the shrinking arctic ice is a consequence of AGW.
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on the other hand you think, that the pretty straight downward trend (and as forecast!) is not supporting the AGW theory? strange!
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can you explain your position? (perhaps also to Goddard?)
only an AGW activist can turn 86 days into 3 years
Where did he ever say that? He said the downward trend was consistent with that theory.
Lucia, thank you for your comments on the null hypothesis in response to my post. I misspoke when I said a rejected null verifies the alternative hypothesis. Of course, it only means the alternative may be true. But I suppose a resulting action might assume the alternative is true.
It’s easy for me to see how hypothesis testing can be used for things that can be easily set up and controlled, such as drug trials, but I have trouble imagining the same kind of testing for attributing changes in climate. I don’t doubt it’s been done, but it must be difficult.
Well, well, well…
http://nsidc.org/data/seaice_index/images/daily_images/N_stdev_timeseries.png