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Comments 131851 to 131900:

131851. 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 ?
131852. Robert S at 14:03 PM on 19 May 2008
        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?
131853. hank at 05:49 AM on 19 May 2008
        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.
131854. Quietman at 04:35 AM on 19 May 2008
        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.
131855. NewYorkJ at 06:53 AM on 18 May 2008
        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.
131856. Quietman at 11:05 AM on 17 May 2008
        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.
131857. Quietman at 10:49 AM on 17 May 2008
        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).
131858. 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".
131859. 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."
131860. chris at 08:52 AM on 16 May 2008
        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.
131861. 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?
131862. 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.
131863. BTN at 05:55 AM on 16 May 2008
        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.
131864. Quietman at 05:52 AM on 16 May 2008
        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.
131865. 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.
131866. 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."
131867. chris at 00:33 AM on 15 May 2008
        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...
131868. 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.
131869. Craig Allen at 14:58 PM on 14 May 2008
        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.
131870. chris at 08:18 AM on 14 May 2008
        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!
131871. 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.
131872. Robert S at 14:35 PM on 13 May 2008
        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?
131873. DWP at 12:48 PM on 13 May 2008
        It's the sun
        Well it's a complicated topic, as usual in climate, and I was skipping over most of that complexity above (especially the important role of clouds!). It's fascinating though, espeically as it is a way of probing how the models are simulating climate versus reality. The canonical reference is Easterling et al., Science, 1997 (p. 364-367). However, anyone who looks into this should also look at the updated work. For example, I'd suggest Stone and Weaver, Geophys. Res. Lett. 2002, v. 29, p. 1356; Braganza et al., Geophys. Res. Lett. 2004, v. 31, L13217; and the summary in the 2007 IPCC report of Working Group 1, in particular, Figures 3.2 and 3.11 and the discussion of those.
131874. Craig Allen at 10:06 AM on 13 May 2008
        Is Pacific Decadal Oscillation the Smoking Gun?
        I posted the following at RealClimate, but folks may be interested here. The following article is about the ‘Weather Olympics’ that will be run alongside the Beijing Olympics, in which international teams will compete to predict Beijing’s weather with 36hr forecasts. >> Teams prepare for weather Olympics Perhaps we similarly need an annual climate forecasting competition. There could be multiple events: 1. Global average temperature. 2. Regional average temperatures. 3. Arctic and antarctic ice extent prediction. 4. Glacial extent. 5. El Nino/La Lina prediction, along with predictions for a bunch of other such phenomena. etc. And where appropriate there could sub-events for different time periods or for trends rather then absolute values. Then we’ll be able to see who’s models and theories stack up to the cold hard facts of reality the best. There seems to be resistance to ideas like this among the scientific community. Not sure why. Climatologists are having trouble getting the general non-scientific community to take the science seriously, rather than the guff from denialists. Something like this would distill the work in a way the public could understand and in a manner that the media would run with.
131875. Wondering Aloud at 01:14 AM on 13 May 2008
        CO2 lags temperature
        lest we forget. http://www.geocraft.com/WVFossils/Carboniferous_climate.html
131876. Wondering Aloud at 00:54 AM on 13 May 2008
        Has solar cycle 24 begun?
        Now you're scaring me.
131877. frankbi at 21:47 PM on 12 May 2008
        Models are unreliable
        "all the facts in Poptech's post are verifiable. I learned them in school." I don't think that's what "verifiable" means. As always, the "criticisms" of climate models are devoid of any concrete, testable facts. -- bi, International Journal of Inactivism, http://frankbi.wordpress.com/
131878. DWP at 14:35 PM on 12 May 2008
        It's the sun
        Good article, but I'd suggest augmenting it with two other points showing that the recent warming is not due to the sun: 1) If the surface warming was due to the sun, you'd expect the entire depth of the atmosphere to be warming. However if the surface warming is due to the release of anthropogenic greenhouse gases, you'd expect the stratosphere to cool, partly due to decreasing stratospheric ozone (which heats the stratosphere by absorbing incoming solar UV radiation) but more because increasing GHGs in the stratosphere more efficiently radiate that ozone-absorbed heat, leading to a net cooling above the tropopause. Observations from satellites show that the stratosphere is cooling, which directly contradicts the hypothesis that the warming is coming from the sun, but agrees with the hypothesis that the warming is coming from greenhouse gases. 2) If the warming were due to the sun, you'd expect the increased shortwave input to the Earth to result in more warming during the day than at night. If the warming were due to anthropogenic greenhouse gases, you'd expect nighttime temperatures to increase more than daytime, since nighttime temperatures are more directly influenced by downward longwave radiation emitted by the atmosphere (as greenhouse gas concentrations increase, they warm and emit more downward longwave radiation, warming the surface). Observations in fact show more nighttime warming than daytime warming. Keep up the good work.
        Response: DWP, find me some peer reviewed studies highlighting point 2 and I'll be more than happy to do a post on the topic. As for point 1 on the cooling stratosphere, that's another topic on the to-do list :-)
        
131879. cce at 05:06 AM on 12 May 2008
        Is Pacific Decadal Oscillation the Smoking Gun?
        GISS does not diverge noticeably from the other temperature series. If any series diverges from the others, it's UAH which shows the least amount of warming. http://cce.890m.com/temp-compare.jpg http://cce.890m.com/giss-vs-all.jpg
        Response: Thanks for the links - here's what the second graph looks like:
        
131880. Dodo at 20:17 PM on 11 May 2008
        Do 500 scientists refute anthropogenic global warming?
        Professor Sugden should be adviced to take note of Richard Feynman's attitude towards science: Any time we come up with something new, our responsibility as scientists is to try find out what is wrong with it. (Don't have the exact quote at hand, but i am sure it was better in the original wording). Now everybody is more concerned about who belongs to which tribe in the climate war than about trying to find out how they themselves might have erred. After every new paper one should ask: how could this be falsified? If that can be answered, we are talking science, if not, politics.
131881. Dodo at 19:23 PM on 11 May 2008
        Is Pacific Decadal Oscillation the Smoking Gun?
        You write: "The long term warming trend indicates the total energy in the Earth's climate system is increasing." Actually, the trend you are talking about is a snapshot of the lower troposphere at about 2 meters altitude (plus an estimate of average sea surface temp). It gives us very little information about the total energy content in the oceans, which are at least an order of magnitude greater as energy reservoirs as the atmosphere. Btw., why do you keep using the GISS temperature data which diverges notably from the other temp time series? Don't you trust HadCRUT or the satellite MSU series, because they show less warming? Or do you have strictly methodological arguments for your choice?
        Response: A good point - the ocean contains something like 84% of the heat absorbed by the earth and it's long term trend is a good measure of the climate's energy imbalance. Hansen 2005 uses the warming oceans to calculate the net forcing at 0.85Wm-2. As for why I use GISS over others, for the sake of this discussion, only GISS and HadCRUT go back to the start of the century. Both show an overall warming trend so the argument of a long term energy imbalance is the same regardless of which dataset you use.
        
        GISS covers the entire globe whereas HadCRUT omits polar regions so you could argue GISS Temp offers a more complete picture of 'global' warming. But in actuality, I just haven't got around to downloading and parsing all the different datasets. Lucia at rankexploits.com takes the average of the 4 major datasets (GISS, HadCRUT, RSS and UAH) which is an interesting approach.
131882. Geoff Larsen at 09:32 AM on 11 May 2008
        Is Pacific Decadal Oscillation the Smoking Gun?
        John, in relation to PDO/ENSO, you are aware, I guess, of Roy Spencer’s theory on internal radiative forcing. From the 2nd link below, “Internal radiative forcing refers to any change in the top-of-atmosphere radiative budget resulting from an internally generated fluctuation in the ocean-atmosphere system that is not the direct result of feedback on temperature“. He has an article in print in the Journal of Climate. From his homepage: - http://www.weatherquestions.com/Roy-Spencer-on-global-warming.htm “Our latest article, "Potential Biases in Feedback Diagnosis from Observational Data: A Simple Model Description", has been accepted for publication in Journal of Climate. It uses a simple climate model to show how daily noise in the Earth's cloud cover amount can cause feedback estimates from observational data to be biased in the positive direction, making the climate system look more sensitive to manmade greenhouse gas emissions than it really is”. Also: - “I have asked the editor of the Bulletin of the American Meteorological Society to consider publishing a paper I have written entitled, "Evidence for Internal Radiative Forcing of Climate Change". I believe that this paper addresses the single most important issue neglected by the U.N.'s Intergovernmental Panel on Climate Change (IPCC): Natural climate variability generated within the climate system in the form of INTERNAL radiative forcing. This paper is a generalization of our paper that has just been accepted for publication in Journal of Climate, and describes how mixing up of cause and effect when observing natural climate variability can lead to the mistaken conclusion that the climate system is more sensitive to greenhouse gas emissions than it really is. It also shows that a small change in cloud cover hypothesized to occur with the El Nino/La Nina and Pacific Decadal Oscillation modes of natural climate variability can explain most of the major features of global average temperature change in the last century, including 70% of the warming trend. While this does not prove that global warming is mostly natural, it provides a quantitative mechanism for the (minority) view that global warming is mostly a manifestation of natural internal climate variability. (This paper is sure to be controversial, and it will be interesting to see how difficult it will be to get published.)” In relation to this see also his post in Climate Science: - http://climatesci.org/2008/04/22/internal-radiative-forcing... If his theory is essentially correct then: - 1. Much of the Net forcing (w/m2) in your chart above, since the 1970’s, can be attributed to internal radiative forcing. 2. Feedback to GHG forcing is much less, or even –‘ve. The latter implies sensitivity to 2 X CO2 of less than 1C. 3. If the PDO has changed to a longer term , –ve phase, with a dominant presence of La-Ninas over El- Ninos, then we are in for a sustained period of less warming or even cooling. 4. Over the longer term the ocean cycles will probably cancel out but we are left with a much smaller increase in radiative forcing & feedback, due to GHG’s, then we have been led to believe. The mistake has been to “extrapolate” the recent warming as if it was almost all due to GHG’s. 5. The theory probably needs to be expanded to include all the major ocean fluctuations.
131883. Quietman at 13:42 PM on 10 May 2008
        Is Pacific Decadal Oscillation the Smoking Gun?
        John I do not believe that there is a single smoking gun anywhere, or conversely, there are many smoking guns. Re: "oscillations cause short term internal variability but don't explain the long term trend which is caused by the energy imbalance" in your response. The North Atlanyic long cycle is not a short term effect. See A Pervasive 1470-Year Climate Cycle in North Atlantic Glacials and Interglacials: A Product of Internal or External Forcing?. And as for the record El Nino year of 1998, see Predictable Winter Climate in the North Atlantic Sector During the 1997-1999 ENSO Cycle. It seems that these record years are a product of various cycles overlapping at just the right time.
131884. Robert S at 13:37 PM on 10 May 2008
        There is no consensus
        Paledriver (54), You misunderstood me: Frankbi said this "Remember the claim that there were 19,000 scientists disputing global warming? During the New York denialist conference ("2008 International Conference on Climate Change"), it turned out there were only _19_ scientists. Looks like the number 19,000 is off by a factor of 1,000." I responded to that point with this "Beyond that, the 19,000 scientists are not all in climate related field, but apparently the Scientific American did some "crude extrapolating" and found roughly 200 climate researchers in the bunch. Again, not 19,000, but still a respectable number." The 200 were supposedly from the OISM petition. And the link in your post at 56 is basically the same thing as frankbi's link at 53.
131885. Quietman at 13:14 PM on 10 May 2008
        Is Pacific Decadal Oscillation the Smoking Gun?
        Steve L I posted some links on El Nino / La Nina in the Volcano thread that you might find interesting. In summary, it says that a volcanic eruption in the Andes always precedes an El Nino. CO2 is released when a volcano erupts as well. But the real impact is the El Nino itself (record highs).
131886. paledriver at 06:10 AM on 10 May 2008
        There is no consensus
        since the topic in this forum is "the consensus" I thought I'd forward this http://www.desmogblog.com/500-scientists-with-documented-doubts...
131887. Steve L at 03:25 AM on 10 May 2008
        Is Pacific Decadal Oscillation the Smoking Gun?
        gx, thank you for disabusing me of the notion I was promoting. I don't remember where I was told that the CO2 in '98 came from the ocean (I think it was a commenter at CA). It shows how much more valuable comments are when they include links to relevant primary literature. However, I still wonder about the reduction in CO2 associated with Pinatubo, and given that different parts of the ocean can be sources while the rest is a sink, I wonder if there is a non-negligible effect on the noise in CO2 trend from oceans. Your links suggest another interesting thing. The stronger effect of forest burning says something about the scale of forest burning for agriculture, don't they? I would assume that there are trends in agricultural burning, but it's trends in precipitation that are observed in atmospheric CO2.
131888. Wondering Aloud at 00:32 AM on 10 May 2008
        There is no consensus
        Phillippe I don't see where you get the idea that the rate of increase of CO2 is unprecedented, or even relevent. It is supposed to be atmospheric content that makes the difference and by those standards we are not at or near anything extreme. So that argument doesn't work. But I guess that is another thread.
131889. Wondering Aloud at 00:22 AM on 10 May 2008
        It's the sun
        SA When you talk about "tipping points" you are taking yourself very far beyond the idea of science. Carbon Dioxide levels have been many times what they are today without ever finding this supposed point so I'm not too concerned with it. I think it is nearly certain that the overall feedback effect is not a positive number, that is kept very quiet because it blows an enormous hole in the panic. I have no trouble with "oil money" if you have no trouble with the IPCC. Which owes it's entire existence to the pre-formed conclusion that CO2 causes warming. Or to the more than 100 times greater money, usually tax money, spent on the other side of the issue. This is a log in your own eye issue if ever there was one. I also don't quite follow how evidence that CO2 does not cause the problem you fear is reason to control it even more tightly. Ignored in all of this of course are all the questions that should probably come first like is warming good or bad or would greater CO2 benefit the biosphere?
131890. AnthonySG1 at 20:34 PM on 9 May 2008
        Al Gore got it wrong
        Seems Gore was wrong afterall: http://scienceandpublicpolicy.org/images/stories/papers/monckton/monckton-gores_10_errors_old_and_new.pdf http://www.johnstonsarchive.net/environment/gore.html http://scienceandpublicpolicy.org/monckton/goreerrors.html http://article.nationalreview.com/?q=YmFiZDAyMWFhMGIxNTgwNGIyMjVkZjQ4OGFiZjFlNjc=
131891. AnthonySG1 at 20:25 PM on 9 May 2008
        Antarctica is gaining ice
        OK smarties. If Antarctica is overall losing ice, then how do you explain the data? http://arctic.atmos.uiuc.edu/cryosphere/IMAGES/current.area.south.jpg The Arctic doesn't seem to be doing so bad anymore, also: http://arctic.atmos.uiuc.edu/cryosphere/IMAGES/current.area.jpg
        Response: Note: the rebuttal above has been updated since this comment was posted, incorporating later references and clarifying that sea ice and land ice are two separate phenomena. Antarctica is losing land ice at an accelerating rate. Sea ice around Antarctica is increasing. The reasons for sea ice increasing in a warming Southern Ocean are complex and described in detail above.
131892. rcglinsk at 15:22 PM on 9 May 2008
        Models are unreliable
        Poptech, nice job of trying to help people understand what computer modeling is and what it can do. Folks, if a climate model doesn't predict past data 100% perfectly then it's useless. You can create an infinite number of different mathematical models that will predict any data series 100% perfectly. To deserve any respect these climate models must predict the previous data perfectly as a start, none should even be thought about unless it does that, and then it has to predict the future better than a simple polynomial fit that also perfectly predicts past data. Frankbi, all the facts in Poptech's post are verifiable. I learned them in school. His analysis is spot on.
131893. Quietman at 08:53 AM on 9 May 2008
        Can animals and plants adapt to global warming?
        chris I agree to some extent but feel that CO2 does not play as big a role as you indicate. Its primarily a feedback mechanism and needs something to feedback from, that is why there is a lag to temp increases. Asd you mentioned Milankovitch cycles, these appear to be a major climate driver but not the only one. Then there is the Fairbridge sea level cycles and his last hypothesis about solar (system) cycles, about which Mackey did a paper on after Dr. Fairbridge passed away. AGW is about an artificial CO2 feedback but there is also a very real natural CO2 feedback mechanism. PS - In my original comment "interesting" was in reference to the potential comments opened up by this particular subject which I am much more familiar with than climate science.
131894. gx at 18:19 PM on 8 May 2008
        Is Pacific Decadal Oscillation the Smoking Gun?
        About April anomaly,over land Asian exceptional anomaly has greatly reduced while antarctica interior has been warm this month,oceans are warming slowly despite la nina rapid decline(there is a 2-3 months lag beetwen ocean temps and ENSO) thus do not expect a very warm month as March(neither cold anyway). RSS satellite data are stable due to land cooling compensated by ocean warming but satellite data are more sensitive to tropical SST change and less to land surface anomaly... RSS land and ocean data: MSU Land Temp MSU Ocean Temp And some information about MSU vs tropical SST
131895. paledriver at 08:13 AM on 8 May 2008
        There is no consensus
        #52, Robert S., I don't know where you got 200 climate researchers were there, but there are over 20,000 climate scientists in the U.S. alone according to the AGU, so even there were 200 in attendance, and assuming they were all skeptics, that's still only about 1%. That would qualify as an overwhelming consensus in my book.
131896. gx at 22:50 PM on 7 May 2008
        Is Pacific Decadal Oscillation the Smoking Gun?
        co2 interannual varibility is mostly due to tropical land fluxes,droughts and fire in the Amazon basin and Indonesia during el nino are the main driver not ocean release/absorption: http://www.atmos-chem-phys.org/3/1919/2003/acp-3-1919-2003.html http://cat.inist.fr/?aModele=afficheN&cpsidt=16775977
        Response: Those are both interesting papers, thanks for the links.
131897. Steve L at 12:59 PM on 7 May 2008
        Is Pacific Decadal Oscillation the Smoking Gun?
        Responding to the possibility of atmospheric CO2 declining this year ... well, the 1998 El Nino was associated with higher CO2 concentrations (presumably due to the Pacific releasing it or failing to absorb much due to warm surface temperature). Also, after Pinatubo there wasn't much increase in CO2 (despite the volcanic release), I guess because it was colder and the ocean surface absorbed more CO2? I wonder if the size of the economy can be reconstructed from trends in CO2 concentrations? That's presumably another factor that COULD contribute to a lower-than-expected CO2 concentration in 2008, although I greatly doubt it.
131898. tbandrow at 02:13 AM on 7 May 2008
        Is Pacific Decadal Oscillation the Smoking Gun?
        I don't think anyone doubts that global temperatures will continue to rise. After all we're continually enhancing the levels of atmospheric greenhouse gas levels, and temperatures are already on their way up to a new equilibrium level "set" by the enhanced greenhouse gas levels already up there. Some people do have that doubt. So, what I'm trying to do is set up an actual conditions of a simple experiment. John's been super enough to basically describe his view of things and its certainly mainstream enough. La Nina ends, and global temperatures will rise for it through the year. If the temperatures rise, then, yeah for Hansen and friends. current models are more validated and the sunspot people made a prediction that failed. we have a weak solar cycle, low flux and sunspots, and the earth's temperature still goes up. That would pretty much do it. If the temperatures fall, though, then yeesh, there's work to do. If there is some sort of mechanism driving the climate than a lot more science needs to be done. But, at least there is a, double yeah for Hansen and friends because they at least have some software base that will need to be adjusted to reflect new things learned. I am skeptical of global warming per se, but that doesn't mean I oppose the use of computer models as a means of encoding scientific knowledge. Rather, I just think the current models suck. It's been my experience that most experts in some other field are horrible programmers, and I'm a computer programmer. I had a look at Hansen's GCM, and although my FORTRAN is very rusty, what they have in there just seems absurd. Some other climate models seem to use the same sort of analytical and modelling techniques used by the finance industry, and that's been a 200 billion dollar fiasco -so far-. I have a sort of a dream that I'm going to write a GCM that doesn't suck and so this immediate experiment interests me. So, I'm not coming from the perspective of denial because a lot of people of a left wing ilk are pushing it. Rather, I see an opportunity for my capitalist friends to really cash in on climate by offering someday a -better model-. So, to other skeptics, I would say, if you don't like the model that is out there kicking out global warming predictions, make one that is more accurate. If you can't, then get out of the climate business and let the pros do their jobs.
131899. chris at 22:42 PM on 6 May 2008
        Can animals and plants adapt to global warming?
        Quietman We know reasonably well well why ice ages occur. In the general case, major glacial epochs (we're in one now) are associated with low atmospheric CO2 levels. For example the present glacial epoch began during the Miocene. The early Miocene glacial period around 20 million years ago (mya) is associated with the late Oligocene-early Miocene decrease in atmospheric CO2....the middle Miocene climate optimum (so-called) with a rise of atmospheric CO2, and then the late-Miocene expansion of the East Antarctic ice sheet is associated with a drop in atmospheric CO2 around 14 mya [*****] Of course these glacial periods also require other factors...for example the Miocene glaciations that heralded the start of the cool period which we're still in, wouldn't have occurred (or at least not to the same extent) without a land mass in the Antarctic for ice to build up on.... Likewise the earliest glacial epoch on Earth more than 3 billion years ago was likely the result of the evolution of the first photosynthetic organisms that produced oxygen which eventually (after turning enormous amounts of oceanic iron salts into iron oxide) destroyed (oxidised) the high methane concentrations that was then "helping" to warm the early Earth. As for the ice age cycles within the current glacial periods, these are also quite well understood, as I'm sure you know. They result from the slow cyclic variations in the orbital properties of the Earth (google Milankovitch cycles) that result in slow and small variations in the pattern of solar irradiation on the Earth. These cycles have associated variations in greenhouse gas concentrations (especially CO2). I think it's quite clear that we are in an interglacial period which still has quite a few thousand years to "run". [*****]e.g. Kurschner WM et al. (2008) The impact of Miocene atmospheric carbon dioxide fluctuations on climate and the evolution of terrestrial ecosystems; Proc. natal. Acad. Sci. USA 105, 449-453. Abstract: "The Miocene is characterized by a series of key climatic events that led to the founding of the late Cenozoic icehouse mode and the dawn of modern biota. The processes that caused these developments, and particularly the role of atmospheric CO2 as a forcing factor, are poorly understood. Here we present a CO2 record based on stomatal frequency data from multiple tree species. Our data show striking CO2 fluctuations of approximate to 600-300 parts per million by volume (ppmv). Periods of low CO2 are contemporaneous with major glaciations, whereas elevated CO2 of 500 ppmv coincides with the climatic optimum in the Miocene. Our data point to a long-term coupling between atmospheric CO2 and climate. Major changes in Miocene terrestrial ecosystems, such as the expansion of grasslands and radiations among terrestrial herbivores such as horses, can be linked to these marked fluctuations in CO2."
131900. John Cross at 11:34 AM on 6 May 2008
        Is Pacific Decadal Oscillation the Smoking Gun?
        Chris: some comments about your point (i). The PDO came about from fishery research in Alaska so I suspect that the warm / cool is a local description (and not really a useful one either). My guess is that we will start to see the term positive and negative phase used more and more. Keep in mind the idea of the PDO is only about 10 years old. Regards, John

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