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Comments 131851 to 131900:

  1. It's the sun
    John, The question of global dimming is a tricky mess and b/c of the heretofore lack of solid field data, a big "known unknown," largely misunderstood & relegated to a "masking" function. V. Ramanathan (Scripps, INDOEX) has consistently found that in the case of aerosols there's a net heating effect, despite the surface dimming. Instead of easing or masking CO2's effect, mid-tropospheric brown clouds ladened with soot & sulfates are driving temperatures up, creating bigger temperature anomalies. The effect is as high as 40% over the vast Pacific region. He's claiming that the window of opportunity can be stretched to 20 years via simple soot mitigation. C. Zender is saying similar things re: soot deposition in the Arctic & Subarctic. There's also a documented cloud-seeding effect of winter storms in the N. Pacific that in turn loft soot into the stratosphere to be borne into the Arctic, eventually causing black icebergs (yes, black icebergs). The odds that we can curtail CO2 fast enough against even the mid-case scenarios are low, so subsuming the evidence against soot under the rubric of "carbon emissions" for fear of diluting the message about CO2 seems to me a mistaken approach. see: http://www.scientificblogging.com/blog/258
  2. It's the sun
    John, The question of global dimming is a tricky mess and b/c of the heretofore lack of solid field data, a big "known unknown," largely misunderstood & relegated to a "masking" function. V. Ramanathan (Scripps, INDOEX) has consistently found that in the case of aerosols there's a net heating effect, despite the surface dimming. Instead of easing or masking CO2's effect, mid-tropospheric brown clouds ladened with soot & sulfates are driving temperatures up, creating bigger temperature anomalies. The effect is as high as 40% over the vast Pacific region. He's claiming that the window of opportunity can be stretched to 20 years via simple soot mitigation. C. Zender is saying similar things re: soot deposition in the Arctic & Subarctic. There's also a documented cloud-seeding effect of winter storms in the N. Pacific that in turn loft soot into the stratosphere to be borne into the Arctic, eventually causing black icebergs (yes, black icebergs). The odds that we can curtail CO2 fast enough against even the mid-case scenarios are low, so subsuming the evidence against soot under the rubric of "carbon emissions" for fear of diluting the message about CO2 seems to me a mistaken approach. see: http://www.scientificblogging.com/blog/258
  3. It's the sun
    Hi Quietman, John, New studies show it's not just about TSI: See: “Is Climate Sensitive to Solar Variability?”, March 2008 “Physics Today”, provided the graph of Phenomenological Solar Signal (PSS) from 1950 to 2007 http://i27.tinypic.com/1zbavyo.jpg CERN's CR & cloud machine: http://aps.arxiv.org/PS_cache/arxiv/pdf/0804/0804.1938v1.pdf FWIW the Aurorae rain hot particles emitting IR & NIR, there's a So. Atlantic Anomaly weakness in the magnetosphere where the radiation belt descends into the ionosphere, and cosmic rays over the Antarctic may cause regional warming via NO2 formation.
  4. A new twist on mid-century cooling
    Just a query about the other events around 1945: would the effects of 5 years of progressively more massive fires from bombing (culminating in the huge attacks on Berlin, Chemnitz, Dresden, and Tokyo, Kobe, Hiroshima, Nagasaki, etc) have contributed to cooling through particulates in the air? Especially with the jump in all the heavy industries (even German output vastly increased in 1943/44) and little regard was taken anywhere for environmental effects. Production increased hugely - Ford alone outproduced the Italian manufacturing industries - on a worldwide scale, and then continued since. While more and more CO2 was being pumped out, so too was air pollution increasing. Even contrails from massed bomber streams (although aircrew usually tried to prevent contrails from giving their position away). Anyway, is this an effect that must be (or has been)taken into account?
    Response: Considering the large temperature drop over sea and negligible drop over land, I'm guessing this effect was not significant.
  5. Warm Penguin Eggs at 21:17 PM on 3 June 2008
    CO2 lags temperature
    I am a layman, but I thought that there was supposed to be more temperature increase in the troposphere (I think) rather than at the surface if the driving force behind rising temperatures was really CO2 levels. In fact I am told the reverse has actually been observed. Doesn't this suggest that something other than CO2 has driven most or all of the warming of the last 30-40 years?
    Response: RSS satellite data of troposphere temperature shows good agreement with models, having a slightly larger warming trend than the surface. UAH data has a slightly lower warming trend. The difference is due to how they adjust their data. What we expect to see in the troposphere and what we observe is within data uncertainty.
  6. A new twist on mid-century cooling
    John Keep in mind that La Nina usually follows El Nino and the time lapse can be very small.
  7. It's the sun
    John I am not sure of the relevance but How Plasma From Superstorms Affects Near-Earth Space from ScienceDaily (May 31, 2008) represents another unfactored aspect of the irregularity of output from the sun.
  8. A new twist on mid-century cooling
    What are the three worst "corrections"? I suspect it's all outlined at Climate Audit, but I don't think there's a nice summary there. You say there was no sudden dramatic shift in sampling method, but the shift in source fleets for data seems to contradict your assertion. If different countries' fleets used different methods.... Whoa, the uncertainty is larger than the change? Are you suggesting that the temperature increase from 1900 to now is not certainly greater than zero? Please clarify. Thanks.
  9. Wondering Aloud at 01:16 AM on 3 June 2008
    A new twist on mid-century cooling
    I have no problem with that Steve. But, I have a big problem with the now over 70 post hoc "corrections" in this already questionable data set; some are nonsensical. Others appear to be a deliberate attempt to make the data fit a preconcieved notion. There was no sudden dramatic shift in sampling methods in 1945 there were sporadic changes back and forth over various methods over a period of 20 years or so. The entire "average" temperature has so much uncertainty that the uncertainty is larger than the change.
  10. A new twist on mid-century cooling
    To #2 and #3 -- when data aren't collected for your purpose, you don't have a choice in how they are collected. It's sensible to adjust them to correct for inconsistencies in collection. I agree that post-hoc adjustments are problematic. But don't you see the data having some value if they match large tropical volcanoes and trends in ice? How were those results fudged? In terms of developing a new interpretation of historical records, I think it would be very interesting to let some skeptical group of scientists outline their method for data adjustments beforehand, put it into code, and then see if their output yielded conclusions that differ greatly from what we currently have.
  11. Wondering Aloud at 23:36 PM on 2 June 2008
    A new twist on mid-century cooling
    Twist, spin, describe it how you will. soon the climate will be clearly shown to be much warmer than ever before and caused directly by humans. This will become firmly entrenched in policy even as the Ice Sheets readvance. The "record" of the last century and a half was never capable of giving the kind of resolution we pretend it has and now the endless "corrections" have passed completely out of the realm of reality. I particularly like that the corrections make the past colder and the present warmer and that the likelihood of so many "corrections" all going the same direction is now already lower than the odds of winning the lottery.
  12. Geoff Larsen at 15:58 PM on 2 June 2008
    A new twist on mid-century cooling
    What a worrying branch of "science" this is! "compensation for a different potential source of bias in SST data in the past decade— the transition from ship- to buoy-derived SSTs—might increase the century-long trends by raising recent SSTs as much as 0.1 C, as buoy-derived SSTs are biased cool relative to ship measurements" Surely if they had followed a scientific approach, and I assume they did, the transition from ship- to buoy-derived SST's would have been accompanied by strict comparison & control between the 2 methods, to iron out any biases, during the transition period. These after the fact adjustments, nearly always in one direction, are becoming a sad indictmenton on this field, as they appear to be flaying in all directions to cover up the weakening of the hypothesis of detrimental AGW. We saw it in the "hockey stick' saga, in the failure to adjust properly for UHI & other biases in the land surface temperature time series, in the tropical troposphere time series, and now apparently in the SST & OCH. Perhaps the 1940's time STT's are incorrect and should be changed. However why wasn't this done years ago & who wants to vouch there are not far more serious problems in the surface temperature series which exaggerate the warming? The bias's in this field (you even see it expressed, non-overtly, in the language that is used) are obvious.
  13. A new twist on mid-century cooling
    I'm not sure what to make of all this. On one hand, as somebody else said, this is a triumph of modelling over data -- the data were problematic and rather than endlessly tweaking the models to get a fantastic and fragile fit, the models were left as they were and seem to give more reasonable results in hindsight. On the other hand, requirements to endlessly(?) adjust data give some folks pause regarding the temperature record and thus the main means of assessing the effects of global warming. Where does this leave us -- with glaciers and ATOC (http://www.ncseonline.org/nle/crsreports/marine/mar-2.cfm)? PS. regarding Figure 4 and natural variability, note there was a big El Nino in 1941 - http://tinyurl.com/5mzakp (from realclimate).
    Response: I did think about mentioning the Southern Oscillation Index which indicates strong El Nino conditions in 1941 - this may play a part in warm temperatures over that period but not so much over 1943 to 1945. This doesn't explain the 1945 discontinuity at any rate - the ENSO signal was filtered out and only furthered the discontinuity.
  14. It's the sun
    clayco Very interesting links but I cant get the top one to work, seems to be something missing.
  15. It's the sun
    http://www.spaceandscience.net/siteb...eport12008.doc John L. Casey “The existence of ‘relational cycles’ of solar activity on a multi-decadal to centennial scale, as significant models of climate change on Earth.” Research Report 1-2008 http://www.spacecenter.dk/publications/scientific-report-series/Scient_No._3.pdf/view Svensmark, H. and Friis-Christensen, E. Danish National Reply to Lockwood and Fröhlich –“The persistent role of the Sun in climate Forcing” Danish National Space CenterScientific Report 3/2007 http://www.sciencedaily.com/releases/2007/08/070801174450.htm Charles D. Camp and Ka Kit Tung Geophysical Research Letters (GRL) paper 10.1029/2007GL030207, 2007 http://www.sciencedaily.com/releases/2007/08/070801175711.htm Anastasios A. Tsonis, Kyle Swanson, and Sergey Kravtsov: Synchronized Chaos: Mechanisms For Major Climate Shifts Geophysical Research Letters (GRL) paper 10.1029/2007GL030288, 2007 http://www.fel.duke.edu/~scafetta/pdf/2007JD008437.pdf N. Scafetta e B.West : Phenomenological reconstructions of the solar signature in the Northern Hemisphere surface temperature records since 1600 JOURNAL OF GEOPHYSICALRESEARCH, VOL.112D24S03,doi:10.1029/2007JD008437, 200
  16. Tom in Texas at 12:40 PM on 1 June 2008
    It's the sun
    2007 global cooling continues into 2008: http://wattsupwiththat.wordpress.com/2008/05/31/globally-2008-significantly-cooler-than-last-year/ And the sun is still blank: www.solarcycle24.com I'm looking forward to this coming winter (but then I don't live in Canada). By next spring, the debate (which is far from over), will "heat" up.
  17. Philippe Chantreau at 01:49 AM on 31 May 2008
    April update on global cooling 2008
    And I meant Phoenix,AZ, of course. Hot air is nobody's exclusivity in election times, it qualifies as a well mixed gas. There will always be weather.
  18. Wondering Aloud at 04:52 AM on 30 May 2008
    April update on global cooling 2008
    Well Phillippe it could be all the hot air from your recent primary election. It does appear you are the exception, as Montana to Ohio at least have been frigid and we may have some very serious agriculture effects if it doesn't change soon.
  19. It's the sun
    And the latest ideas on Solar Inluence in climate change.
    Response: The idea of global dimming is covered somewhat here. The most disturbing element of global dimming is expressed well on the PBS page: "Is global dimming masking the full impact of global warming? Some climate experts worry that it is, with the possible consequence that as we reduce pollution, the climate will heat up to unprecedented levels."
  20. It's the sun
    John You might find this NASA clip interesting: A shock wave following a flare
    Response: That's an awesome animation - just imagine the size of that shockwave, the magnitude many times the size of the Earth!
  21. Philippe Chantreau at 17:52 PM on 29 May 2008
    April update on global cooling 2008
    Sorry, WA. Over here, May has seen the Oregon coast reach triple digits, before Phoenix, AR. A first in recorded history.
  22. Wondering Aloud at 04:52 AM on 29 May 2008
    April update on global cooling 2008
    Wildly cold would be a good descripyion on May in the Midwest. We had freeze warnings for Memorial day and have only climed very briefly into the 70's this month.
  23. There is no consensus
    Robert S. I did understand you. What I'm saying is #1, you don't know that the 200 that were, supposedly, there all disagree with the consensus and #2, 200 is an insignificant number when you realize that there are over 20,000 in the U.S. alone, and that this convention drew, I believe they claim, from all over the world.
  24. Misinterpreting a retraction of rising sea level predictions
    BTN, Well, there IS an asymmetry in the situation: - the expectation of GW fits into the framework that is CONSISTENT with the atmospheric physics that we know about. - the claim that GW is not happening poses problems for this framework. Specifically, what happened to the greenhouse effect? And if the answer is, There IS not greenhouse effect, then the problem becomes, Then why is the Earth's surface so warm, compared to what it "should" be? Since the expectation of GW is the result of the framework theory, it has to be DISPROVEN to be invalidated. The GW-denying theory is NOT consistent with the rest of atmospheric physics, so if you want to make that claim, you do have a higher standard of evidence to meet.
  25. Empirical evidence for positive feedback
    "It's generally agreed that 1° increase would occur from a doubling of CO2 alone." Both the skeptics and most of the alarmists make this claim. But its a totally dubious and unscientific claim for starters. It appears to assume that the molecules in the air are totally static. It assumes that pockets of molecules won't move upwards as a result of being warmer than the molecules around them. This one degree increase is a flat earth calculation. Its as if the sun is twice as far away, the earth is flat, and its always noon and so the whole flat world is the equator. It also takes no account whatsoever of imbedded energy in the oceans or in the entire planet. Everything is wrong with this assumption. Everything about this assumption is unscientific. So this particular paradigm isn't getting past its first assumption. But it just gets worse from there. Because while on the instantaneous level water vapur is a greenhouse gas.... What the water vapour is really doing is conveying energy out into space. So anyone not taking a mentally deranged instantaneous snapshot of the matter will realise that resultant increased water vapour is a negative, rather than a positive feedback scenario to whatever the CO2 is going to do. The process of wind whipping along the ocean and creating water vapour is a process of REFRIGERATION. This is why this pandemic of lying continues. Because the skeptical side of the argument knows that the other guys are wrong since thats what the empirical evidence says. But the situation can't progress, because the political motivation of the committed leftist liars has so "polluted the air" as it were, that no-one will dare putting up alternative paradigms to the hairbrained standard model.
  26. Will Nitschke (www.capitaloffice.com.au) at 03:13 AM on 24 May 2008
    Global warming stopped in 1998, 1995, 2002, 2007, 2010, ????
    Ok over the last 10 years the temperature has cooled slightly, or stayed about the same, or maybe even warmed slightly. But whatever the real outcome, the assertion that we are going through a radical period of accelerated warming and are on the verge of a climactic catastrophe (tipping point), sounds very very dubious a statement indeed... but isn't this the concept that inspires all the work that goes into a website such as this?
    Response: Personally, the inspiration for this website is not about catastrophes or end of the world stuff. I'm more concerned about the incremental changes that will and are impacting society - decreasing food production in low latitude countries which are least able to adapt, decreasing water supply which will only be exacerbated over time. Sure, there is some hysterical doomsday alarmism out there (from both sides). But for those lacking the foresight to care about the world they hand over to future generations, this is something that will effect us now and over the next decade.
  27. April update on global cooling 2008
    UnknownfromBulgaria I did a quick check on stats for my area to demostrate my point: Month Avg.Low Avg.High Record Low Record High May 1 38° 61° 20° (1931) 82° (1930) May 2 39° 61° 25° (1943) 84° (1942) May 22 45° 69° 29° (2002) 88° (1941) Today 39° 50° Today is fairly representative of the this month, running between 10 and 20 degrees F below normal highs and about 10 below normal lows. What I noticed after posting the data was the dates. I guess I need to check this out some more.
  28. April update on global cooling 2008
    UnknownfromBulgaria It isn't just Russia, We have had cold weather and snow in the NE U.S. as well this week, first time in a long time for May (but it has happened before). The entire northern hemisphere {with the exception of western europe last I heard} has seen this anomaly. See the PDO post and comments
  29. UnknownfromBulgaria at 23:29 PM on 22 May 2008
    April update on global cooling 2008
    However,there is one thing I'havent understood. What might have caused this significant cooling in Russia in April,compared to march 2008.Can someone pose a suggestion which might explain that.Did some phenomenen like a volcano in Siberia,for example occur in the end of March or in the begining of April ?
  30. Models are unreliable
    "on the Skeptic article, by the other author on the same issue." I didn't think Koutsoyiannis was writing up a "skeptic article", but rather an assessment of climate models. "'Cohn and Koutsoyiannis, one of them the author of the very paper that I had criticized, sat down next to me. We nevertheless had a very civilized and friendly chat, deciding to disagree on the matter of natural trends. But Dr. Koutsoyiannis commended us for being respectful in our reply to his comments. I think this is a very important issue – we have to be respectful, sincere, and show courtesy in our criticism, even when we argue why we think that a paper has flaws. ...'" I don't see how this is relevant-- the paper that Rasmus criticized was a paper titled "Nature's style: Naturally trendy" by Timothy Cohn and Harry Lins. The "But Dr. Koutsoyiannis commended us for being respectful in our reply to his comments" part of it involved comments made by Koutsoyiannis on a 2006 realclimate thread. So hank, I am not exactly sure where you are getting at with your comment here. Just a little background information on Koutsoyiannis?
  31. Models are unreliable
    http://www.realclimate.org/index.php/archives/2008/05/what-the-ipcc-models-really-say/#comment-87205 on the Skeptic article, by the other author on the same issue. Koutsoyiannis mentioned here: "Cohn and Koutsoyiannis, one of them the author of the very paper that I had criticized, sat down next to me. We nevertheless had a very civilized and friendly chat, deciding to disagree on the matter of natural trends. But Dr. Koutsoyiannis commended us for being respectful in our reply to his comments. I think this is a very important issue – we have to be respectful, sincere, and show courtesy in our criticism, even when we argue why we think that a paper has flaws. ..." http://www.realclimate.org/index.php/archives/2008/04/egu-2008/ Use the Search box at the top of the RC page, paste in: Koutsoyiannis Dr. Koutsoyiannis posts there in two of the discussions.
  32. Less than half of published scientists endorse global warming
    This PDF is a study of the confidence levels of climate scientists and how they changed from the late 1990s to the early 2000s. The Perspectives of Climate Scientists on Global Climate Change I think that this speaks louder than endorsements.
  33. April update on global cooling 2008
    From the link: "This exact same phenomenon plagues the coverage of climate change. We're now analyzing the release of each month's global temperature data as if one month could provide some statistically meaningful insight on the long-term picture." Indeed. There seems to be a fanatical frenzied obsession now among blogs, op-eds, and contrarians regarding short-term data. They are eager to exploit the recent la Nina for everything it's worth. Much of the general public doesn't seem particularly astute when it comes to general statistics and year-to-year and month-to-month volatility. Some are easily fooled by graphs of temperature trends using selective data and baselines. Part of this might have to do with the increased likelihood that the U.S. will be passing meaningful (arguably) legislation to control emissions within a year or so, a fear I don't entirely understand.
  34. It's the ocean
    John In keeping with this thread, you may be interested in a paper from Nature: AMO will stop warming until 2020. This seems to coincide with SSC24 as well. I added two links dealing with the AMO, PDO and ENSO cycles in Is Pacific Decadal Oscillation the Smoking Gun? as well as the ENSO related posts in It's volcanoes (or lack thereof) about the cause of El Nino/La Nina.
  35. Is Pacific Decadal Oscillation the Smoking Gun?
    WA and Chris Wiki gives a good explanation of the AMO: Atlantic Multidecadal Oscillation Or this may be better as it includes a graph and a link to the NASA source paper: Multi-Decade Climate Cycles Also I put a link in comment 22 about the AMO (just in case you missed it).
  36. Wondering Aloud at 23:27 PM on 16 May 2008
    What does CO2 lagging temperature mean?
    http://www.geocraft.com/WVFossils/Carboniferous_climate.html The CO2 temperature connection leaves much to be desired on any time scale I can find, 800 years wrong way over the last 600K years is only a bit of it. It is clear that temp increase can cause carbon dioxide to increase. The converse being true is your working hypothesis but it is questionable because it just doesn't fit the record. We have warm periods with low CO2 and ice ages with high CO2. Maybe convection and cloud effects simply overwelm the supposed radiative issues.
    Response: It's important to remember that as you go further back into the past, solar activity falls. Around 550 million years ago, solar output was about 5% less than current levels. So this needs to be kept in mind when calculating the effect of higher CO2 levels. This is discussed in more detail in "CO2 was higher in the past".
  37. Wondering Aloud at 23:20 PM on 16 May 2008
    What does CO2 lagging temperature mean?
    To quote the late Reg Newell on this topic "I'm saying that's not at all evident."
  38. Is Pacific Decadal Oscillation the Smoking Gun?
    Wondering Aloud, It's a very good question, and one that Keenlyside et al (link in John Cross' header article above) don't really address in their paper as far as I can see. The lack of success of their "hindcasts" with respect to reality, might lend us to question whether their prediction of a short-term slowdown of warming has much merit. There's also the question of whether the "warm" or "cool" phases of the PDO make a significant contribution to the Earth's global surface temperature anyway. After all the PDO is just one of the Ocean oscillations. If one overlays the AMO (Atlantic Meridonal Oscillation) with the PDO, for example, it's pretty much a mirror image with a cold phase in the early 20th century up to the 30's, a warm phase from then through the early 60's and then a cool phase to 2000. So overall, ocean currents might be essentially neutral on short timescales as well as longer (decadal) ones... Unfortunately I can't find a picture of the AMO, but this is described in a recent paper in Geophys. Res. Lett.: K. E. Trenberth and D. J. Shea (2006) Atlantic hurricanes and natural variability in 2005; Geophys. Res. Lett. 33, L12704, doi:10.1029/2006GL026894.
  39. Wondering Aloud at 08:20 AM on 16 May 2008
    Is Pacific Decadal Oscillation the Smoking Gun?
    Why do we think it is reverting to a cool phase and not just a dip like in 2000?
  40. Wondering Aloud at 08:13 AM on 16 May 2008
    La Nina watch: March update
    Yeah looks like it is ending but, we can still hope, April temp was down and I just love making everyone fuss. I did after all predict a double dip.
  41. Misinterpreting a retraction of rising sea level predictions
    Very funny how so many attribute Global Warming trends to human activity, yet when defending periods of no warming, or cooling, they claim natural causes.
    Response: The cooling period between 1940 to 1970 was due in some part to human activity as sulfate pollution increased atmospheric albedo, preventing as much sunlight from reaching the earth's surface.
  42. April update on global cooling 2008
    I guess we can start looking at the next El Nino that were signalled by the recent eruptions in Chile.
  43. Wondering Aloud at 04:03 AM on 16 May 2008
    Is Pacific Decadal Oscillation the Smoking Gun?
    John Cross and I made a predictions on global temp a few months ago based on La NIna, where are those now? I know so far I am right on (due to brilliant lack of specificity and a random wiggle in the GISS data)so I want to review my brilliant contribution and maybe enter it in the proposed contest.
  44. Will Nitschke (www.capitaloffice.com.au) at 19:23 PM on 15 May 2008
    Models are unreliable
    Here is a new study that evaluates the accuracy of climate models: D.Kutsoyiannis,N.Mamassis,A.Christofides,A.Efstratiadis,􀈱S.M.􀈱Papalexiou Department of Water Resources and Environmental Engineering National Technical University of Athens (www.itia.ntua.gr) http://www.itia.ntua.gr/getfile/850/3/documents/2008EGU_ClimatePredictionPrSm.pdf Or to sum up the study: "Climatic models generally fail to reproduce the long term changes on temperature and precipitation."
  45. Is Pacific Decadal Oscillation the Smoking Gun?
    pico, Yes i did interpret your Climate Olympics event as a "year ahead" prediction jamboree. Such a prediction was suggested further up the thread and i had that in mind when I read your post... So, actually I'm pretty much in agreement that such an event would be a good idea as a focus of research towards the short term predictions (a few-10 years) that would be very useful for all sorts of endeavours, but which are now (in my opinion) little better than "guesses". Some effort should be made to ensure that the public perception wasn't "hijacked" with the inference that unsuccessful predictions indicate fundamental misunderstanding of the climate system in its response to persistent greenhouse forcing. I think we all agree that very short term forecasting is bound to be complicated by all of the essentially unpredictable (for now anyway!) elements of ocean circulation, solar activity and potential volcanic eruptions... There is some precedent from other research fields for the sort of regular event that you propose. The protein folding modellers have a biannual event (CASP) in which a competition for the most succesful protein structure prediction is held (i.e. the modellers are given the amino acid sequence of a protein who's crystal structure has recently been determined but not yet released, and they have to model the structure from the sequence, based on the known forces governing the folded state structures of proteins). I guess the difference between CASP and your Climate Olympics is that the protein modellers find out immediately who has done the best job, whereas the climate modellers will have to wait a few years to see who's best nailed the prediction...
  46. Wondering Aloud at 22:55 PM on 14 May 2008
    Is Pacific Decadal Oscillation the Smoking Gun?
    The squeeky dog might win. I think you eliminated everyone else with the last lines of the paragraph.
  47. Is Pacific Decadal Oscillation the Smoking Gun?
    Chris, 1) You are assuming I'm suggesting that the Climate Olympics events would be all be about predicting next year's climate. Not at all. While the competition might be annual, the timeframes for some events might be for periods that are much longer. The time frames would need to be selected very carefully by scientists with a comprehensive understanding of this. In fact the process of choosing the suit of events and associated time-frames would itself be very informative to the wider public. The event suite might be summarized as a grid of phenomenon x timeframe with many cells blacked out because it is not possible to predict all phenomena over all time-frames. 2) Clearly you would not be able to let every second clown and his squeeky dog enter with predictions plucked out of his/her silly hat. There would need to be criteria, such as the requirement that the predictions be based on a sound conceptual models of atmospheric and ocean physics. 3) As the science and models advance, it would be necessary to re-examine the event suit annually. So extra events might be added over time, but only after careful consideration.
  48. Is Pacific Decadal Oscillation the Smoking Gun?
    pico, I don't see any positive value in an "annual climate forecasting competition". Apart from anything else it doesn't make sense. One can't "predict" "climate" on an annual basis bacause year to year variation isn't "climate"..it's more like "weather". The whole thing (Keenlyside et al included) is a delusion. We understand quite well the essential elements of the Earth's energy budget (e.g. an enhanced greenhouse gas concentration will result in a higher equilibrium temperature anomaly, all else being equal)...however we don't have a good handle on either the internal variations of the climate system (El Nino's, la Nino's and various other ocean circulation variabilities), nor the unpredictable elements (non-cyclic solar contributions; volcanic contributions...)... so whereas we can make reasonably good predictions of the Earth's temporal temperature evolution [e.g. Broeckers 1975 prediction...or Hansen et al's mid-1980's climate model extrapolated into the future (our now-present)] under various emission scenarios, no-one can truthfully predict whether the temperature anomaly for the year ahead will be the same as last years or plus 0.1 oC or - 0.1 oC. However we can rather more reliably assert that in 10 years time the Earth's temperature anomaly will be fluctuating around a level that is 0.15-0.25 higher than today's, and that in 20 years time the Earth's temperature anomaly will be fluctuating around a level that is 0.3 - 0.5 oC higher than the present one, given a continued greenhouse gas emission trajectory. By throwing the floor open to all-comers with all their "guesses" the whole thing is likely to become a circus with the correct "guess" likely to be be "correct" for the wrong reasons. Unless one can predict any solar fluctuation (it can't be done outside the certainty of the 11 year solar cycle)...El Nino's and La Nina's (can't be done except on a probabilistic basis), volcanic eruptions (can't be done), ocean current fluctuations (PDO, AMO, SOI et al) (no real basis for prediction there either), there is no basis for meaningful year on year prediction... However the evidence supports the conclusion that on a decadal timescale, most of these fluctuations roughly cancel with little net warming/cooling contribution (medium to long term variations in solar output being a potential exception), whereas a continually increased greenhouse forcing results in a postive trend which is apparent on a decadal basis rising above the "noise" that modulates the Earth's temperature anomaly on a year to year basis. If one examines the Earths temperature evolution (see Figure in post #25 just above) that's blazingly obvious. Notice that our uncertainty with respect to yearly forecasting doesn't indicate an incomprehensibility of the climate system. We can understand the temperature evolution rather well in hindsight. We can observe El Nino's, La Nina's, volcanic eruptions and so on, and understand how they influence the temperature evolution on a year-on-year basis rather well... ...we just can't predict all this "noise". It's foolish to pretend that we might be able to, and to pretend that we can is to put the charlatans and any climate scientist foolish enough to engage in this sort of prediction on an equal basis...because it's just guessing. Now of course someone might come up with a profound understanding of some of the presently apparently stochastic elements of the climate system (e.g. it might become apparent how one can make reliable predictions of El Nino's or the PDO)...in that case fine..predict away!
  49. Wondering Aloud at 04:33 AM on 14 May 2008
    CO2 lags temperature
    If you are refering to the saturation idea, credible yes, possible yes, right? I just don't know. It does look to me like most of the forcing predicted from a doubling of CO2 should have already occured unless there is a big time lag in the system that is un accounted for. this is why I asked on other threads if there was a lag of perhaps 30 years we didn't have identified. Without it we are down to only those large, but not now apparent, feedback numbers or a relatively small total signal on the order of 1 C.
  50. It's aerosols
    "...That's not just semantics - take aerosols out of the equation and in the absence of any other forcings, global temperatures would remain steady." This doesn't make any sense--when you "take aerosols out of the equation" doesn't that mean more EM radiation is reaching Earth, warming it?

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