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All IPCC definitions taken from Climate Change 2007: The Physical Science Basis. Working Group I Contribution to the Fourth Assessment Report of the Intergovernmental Panel on Climate Change, Annex I, Glossary, pp. 941-954. Cambridge University Press.

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Comments 126451 to 126500:

  1. The physical realities of global warming
    John Appreciate this summary. Most folks would find the latest IPCC release a bit of a challenge. Great to have a link to help with that. All the best.
  2. What do the hacked CRU emails tell us?
    ENSO events.
    Models generate ENSO-like events.
  3. What do the hacked CRU emails tell us?
    They do not explicitly simulate convection, for example.
    Actually, Model E does include a cloud convection module that among other things generates anvil-heads that break the troposphere/stratosphere boundary, if I read the documentation correctly (I've not read the underlying paper, which is clearly referenced in the code, though). It's optional, not sure when they use it. Each grid halving requires at least 8x the computing power if nothing else changes, I believe. You get four "boxes" where before there was one, thus that's 4x the amount of computation. Plus the time step must be shrunk by half since propagation times are linear to the grid size. Therefore I get 8x more computation needed. Over time they've also increased the number of layers the atmosphere is sliced into, added more physics, etc so you can see why progress in model resolution etc improves incrementally, not by giant leaps.
  4. The physical realities of global warming
    Taking a page out of the recent political event, I have to note it's quite a devious "trick" those scientists pulled in adding satellite observations to the tide gauge data. Such blatant data manipulation! Ari, Skeptics tell us Arctic sea ice is growing (starting in 2007 of course). Models and alarmists are wrong again. That graph above, therefore, is propaganda.
  5. What do the hacked CRU emails tell us?
    Mizimi, he/she asked you to list the known factors that the models do not include. Your list is a mish-mash of what they are not particularly good at simulating, mostly b/c of grid spacing issues. The latest AOGCMs include atmospheric chemistry, and the grid spacings are closer to one degree lat/lon. They do include/reproduce clouds, aerosols, internal climate modes, WV, ET etc etc. Read Chapter 8 in AR4. They do not explicitly simulate convection, for example. Anyhow, what the heck has this to do with the CRU email hack?
  6. The physical realities of global warming
    Climate skeptics usually make a big deal about how bad IPCC-models are, but for some reason the situation with Arctic sea ice extent doesn't seem to be interesting to them, and yet there seems to be a real gap between the models and the observations. Strange.
  7. What do the hacked CRU emails tell us?
    # 76: dhogaza...model inadequacies: Cloud and subsequent albedo Aerosols ( not just ours but plant aerosols..terpenes) ENSO events. Alterations to WV distribution patterns caused by land use changes & deforestation. Rate of evaporation/precipitation in tropical zones. Relationship between wind & evaporation over oceans ( wind is affected by SST and SST is affected by wind speed) Current models work in pretty large cells where it is not possible to do anything more than generalise.. a good example of thjis is oceanic circulation; compare a satellite pic of circ patterns and then overlay a 200km cell and see what the models miss.
  8. What do the hacked CRU emails tell us?
    Re #97. Thanks dhogaza, I was worried I had not referenced the diagnosis correctly. "Truthseeker" re #92, read the Copenhagen Diagnosis, especially the grey box on page 15. That said, as SNRatio noted, the data and facts are there, but are your willing to be open minded and unbiased enough to embrace them? Liberally cut and pasting text from other sources without any associated discussion or context is not citing evidence "Truthseeker", nor is it constructive. That said, NeilP does seem to be now engaging people, so that is a start.
  9. What do the hacked CRU emails tell us?
    thats fine for you, but when I see someone talk out of both sides of their mouth, they have a credibility issues with me. I am sorry that you bias lets you forgive the discrepancy when it is convenient for you.
    He links to his relevant paper right in the e-mail you claim you understand better than he himself. Go read the paper, if you don't, you have no idea as to the context of the argument he's making in his e-mail.
  10. What do the hacked CRU emails tell us?
    On Tuesday the IPCC released an update to the AR4 for Copenhagen. You can view and/or download the file at: http://www.copenhagendiagnosis.com/
    Just for clarification, this isn't an IPCC update to AR4, but rather an effort by a couple of dozen researchers working on their own. As it happens, many are lead IPCC chapter authors, etc, but it's not IPCC-vetted. Which, if denialists are to be consistent, gives it *more* credibility than AR4, right, since IPCC is just an anti-science political body? :)
  11. Water vapor is the most powerful greenhouse gas
    John, the embedded video is just a blank box for me. But I'm using Firefox on a Mac; maybe it's platform-specific.
    Response: Hmm, I see a blank box in Firefox on the PC but it works fine in Internet Explorer. Any YouTube boffins have any solution to this conundrum?
  12. East Antarctica is now losing ice
    More about not acting when there is uncertainty. That's a completely flawed notion for risk management. To make rational choices for each alternative, you have to integrate the cost-benefit function over the stipulated pdf for the outcome, to get the expected cost of that alternative. Then, there may be enough with a relatively small probability of a very expensive outcome of an alternative to have reason to discard it as policy. So we may find some "alternatives" are not really options, after all. If you don't base decisions on such principles, you're not rational. Humanity has a long and sad record of acting non-rationally. Just to use the present situation as an example: If the present levels of radiative forcing are already enough to cause global deglaciation over time, we may already have blown it. The accelerating ice loss of Greenland and the Antarctica indicates that we now can't set the probability of that to zero. We don't know the costs, they're very much dependent on how fast it happens, but in any case, they will be huge over time. Could we have known this in advance? No. Does that lack of knowledge entitle us to set the probability of it happening at present forcing levels to zero? Absolutely no, as is evidenced by this post.
  13. Humans are too insignificant to affect global climate
    I’ve always been puzzled as to why people think humans are too puny to have any effect on the planet. Far smaller organisms than us have had a significant impact. Just look at the Great Barrier Reef, the White Cliffs of Dover or the Peak District. None of these would be present, or would be substantially different, if the results of the blind unthinking actions of primitive creatures had not accumulated over long periods of time. Neither would we be breathing an oxygen-rich atmosphere were it not for the photosynthetic activity of plants over millions of years. OK, none of this was deliberate or short-term, but it shows that really insignificant life forms can have an impact on the planet. As for humans, we can and have created deserts, made semi-desert more arid and the like by over-grazing of livestock, over-intensification of non-sustainable agricultural practices and deforestation. None of this is necessarily irrecoverable in the long term, given the will, the power and the knowledge of how to undo the damage, but our impact on so much of the biosphere is indisputable. Of itself this does not prove global warming, but it does invalidate any assertions that we are too unimportant to have any effect
  14. High CO2 in the past, Part 2
    @DrMike I really appreciate your questioning of all assumptions - that's important part of what good science is about. Somewhat on a tangent, I would like to comment on the principle of "early falsification", i.e. an apparent lack of fit between theory and data, in a situation where either theory or data, or both, is not very comprehensive. It may make good tactics, but bad strategy. Imagine a "data-driven" response to Copernicus: "You maintain those planets move in circles, but the data clearly shows they don't! That simplistic circular hypothesis could make a good heuristic, but to get at the real science, you have to resort on the computation machinery dating back to Apollonius, which describes this with as much precision as you like. If it doesn't fit, you must aquit!" Which is, factually, quite correct. But enter Kepler and Newton. For may of us, it's not about believing in it. We would rather be thrilled at getting better theories. To work with, that's what it's about. Working.
  15. What do the hacked CRU emails tell us?
    "billbrent Really apologize for mixing part of your post with another's. Scrolling up&down error. As for Trenberth, I think chris has explained things pretty well. I think you may think of this as "understanding the physics" of first and second order approximations: The first order terms, most relevant for the public warming debate, are in place reasonably well, but higher order needs more involved analysis of details. And phenomena like small systematic variations in the cloud albedo may have "huge" effects in this more detailed analysis. Lindzen&Choi's paper may turn out to have the opposite effect of what you think. You should check out Roy Spencer's comments on it on Watts Up With That, if you don't think that site is too biased towards warmism, then. You might also download and go through Lindzen's presentation "A deconstruction of global warming". That was really a deconstruction for me. But not of global warming. About "acceptable" temperature increases: I think the present rise is enough already to be of great concern, and a 1 degree rise could have huge negative impact. It very much depends on how variability develops.. With very small variability, 1 deg could be much more acceptable than with high variability.
  16. What do the hacked CRU emails tell us?
    TruthSeeker, "So why don't we exclude all the tree ring data, since its be proven to be faulty?" Never this proof appeared, not even in the "secret conspiracy emails"; on the contrary, they still prove usefull for temperature reconstructions. Instead, some trees in some sites are known (no breaking news here) to show a (relatively) recent divergence problem. And here comes the shouting on the hidden data ... "IF this is true, it would change my view from a skeptic to a believer." The data are there, the anticipated effects of warming too; you are free to distrust them if you're happy with this. I'm sure we'll not see you change your "view from a skeptic to a believer" any soon ;)
  17. East Antarctica is now losing ice
    HumanityRules, i think we all are happy to have more and more accurate data. In the meanwhile, though, we cannot say the data are plainly wrong every time. What is needed is continuosly adjust the estimates when new and more accurate measurements becomes available. The correction for the new results on PGR appears to be significant but do not change the main conclusions. Also, keep in mind that PGR is at work on the long run and the changes in the trends are almost unaffected. The only point i see with the paper is that the data cover a limited time range and we do not have a model that can reproduce this trend with any confidence. So, altough the trend appears to be significant with respect to the interannual variability, we cannot anticipate that it's the beginning of a new long term trend. And for sure i don't want to follow the alternate claims "it's growing" and "it's shrinking" every couple of years ... :)
  18. What do the hacked CRU emails tell us?
    dehogaza, I love it, when its posted in an email that he presumes is under the cover of the night, you disbelieve it, but when its clearly a public statement made with the impression he wants to give you claim. "Well, Trenberth is on record as saying that the kind of conclusions you draw do misrepresent his work. I'll take his word on it, sorry." thats fine for you, but when I see someone talk out of both sides of their mouth, they have a credibility issues with me. I am sorry that you bias lets you forgive the discrepancy when it is convenient for you.
  19. What do the hacked CRU emails tell us?
    "I don't see why people seem to have such a hard time understanding this issue. There is a variety of proxy data available as well as the instrumental record. There is no problem with omitting proxy data that deviates from observed results." So why don't we exclude all the tree ring data, since its be proven to be faulty?
  20. What do the hacked CRU emails tell us?
    Some one please show me this: it’s pretty obvious that the IPCC projections have been conservative. CO2 emissions have followed IPCC projections since 1990 quite closely. Temperatures have risen at a rate that is right at the top end of the IPCC projections" IF this is true, it would change my view from a skeptic to a believer.
  21. What do the hacked CRU emails tell us?
    NeilPerth, Thanks for your postings. I like how when you post like you have done, the others wine how you are "cutting and pasting," but when you don't they scream "site the evidence."
  22. East Antarctica is now losing ice
    "Thus we see the inherent flaw in the notion that we shouldn't act on climate change while there is still uncertainty." If the changes now being detected in Antartica are a function of the fallout from the entire planet's modern industrial history, it doesnt seem like we have a lot leverage short of some very drastic "action". In the meantime, people have eat. Likewise, penguins can fend for themselves.
  23. East Antarctica is now losing ice
    #3 response With respect to InSAR data (taken from Chen 2009 reference 4) "Ice thickness, H, is deduced from surface elevation above mean sea level with reference to the GGM02 geoid". GGM02 is derived from data generated from GRACE so is it legitimate to say the Chen GRACE data is "independently confirmed" by InSAR data? Tapley, B. et al. GGM02—An improved Earth gravity field model from GRACE. J. Geodesy (2005) (doi:10.1007/s00190-005-0480-z). And still the GPS data suggests the the GIA assumptions in Chen are wrong. Do you think there is any value in the GPS data?
  24. Water vapor is the most powerful greenhouse gas
    Greenman3610 just posted a Climate Denial Crock of the Week on water vapor.
    Response: Thanks for the heads up, I've embedded the video above.
  25. East Antarctica is now losing ice
    The measurement of ice loss is dependant on two halves of a sum. Firstly apparent mass loss is measured (e.g. by GRACE). This mumber is then adjusted to take into account movement (rise/fall) in the rock of the antarctic, my understanding is this is called Post Glacial Rebound or GIA. Two computer models have been popular for measuring this second part of the sum, they are called IJ05 or ICE-5G. In recent years GPS sites have been setup in the antarctic. Two studies have looked at the information coming from this GPS data Bevis, M., et al. (2009), Geodetic measurements of vertical crustal velocity in West Antarctica and the implications for ice mass balance, Geochem. Geophys. Geosyst and http://rses.anu.edu.au/geodynamics/tregoning/36.pdf Both these studies suggest that the measurements of GIA are wrong. In summary the assumption has always been that antarctic was rising due to loss of ice from the last ice age when in fact the actual GPS measurements suggest stasis. The first of the papers suggest the ice mass loss for part of West antarctic is over estimated by 33Gt/yr although states that really the sums have to be done again with this new information. There is no estimate of the error in the East Acrtic data. Would you be interested to see the GRACE data analysed with glacial rebound calculated on the basis of GPS data?
    Response: Chen 2009 takes GIA into account when calculating the mass loss from GRACE data. This is then independently confirmed by the InSAR satellite data which is not affected by GIA.
  26. What do the hacked CRU emails tell us?
    This is off topic, but may help address some of the questions that have been raised here. On Tuesday the IPCC released an update to the AR4 for Copenhagen. You can view and/or download the file at: http://www.copenhagendiagnosis.com/ Sorry for the intrusion.
    Response: I've posted a review of the Copenhagen Diagnosis in The Physical Realities of Global Warming.
  27. Record high temperatures versus record lows
    Steve L, I have made an exhaustive search though the literature and have found only one paper which explores relationship between lighting activity and soil moisture (my interest) in Mongolia. This is a very new field. I can track the paper down if you like. Regarding changes in the rainfall, the IPCC update which was released today includes a couple of references to large-scale trends in precip. in the 20th century (e.g.., Zhang et al., 2007, Nature). Check it out at: http://www.copenhagendiagnosis.com/ PS; Also try this one for lightning land use interactions. Kilinc and Beringer 2007, J. Climate (AMS) There are more on this topic (land use lightning).
    Moderator Response: [Daniel Bailey] An open-access copy of Zhang et al 2007 can be found here.
  28. What do the hacked CRU emails tell us?
    Thanks for the reference to Chris Colose's website. Much appreciated.
  29. East Antarctica is now losing ice
    Sorry if this is answered elsewhere, is there expected behavior for Antarctic ice? For example, are there estimates for ice loss as a function of time? Is the loss due to CO2 concentration increases expected to be greater than other causes of ice variation? The reason I ask is that I can just see a time in a couple of years when the ice is growing again and the whole controversy starts again. Head it off at the pass.
  30. What do the hacked CRU emails tell us?
    Thank you, Chris. I think I understand what you're saying about the broader certainty. Kind-of like the uncertainties over gradual evolution vs punctuated evolution against the broader background of the certainty of evolution itself. Right? I'll take a look at the links you provided for the radiative forcing explanation. Do you know if anyone has specifically address Lindzen's recent claim that satellite readings of LWIR data indicate a negative feedback rather than a positive one?
    Response:

    Lindzen's claims are addressed at Chris Colose's website (another topic for a future post).

  31. What do the hacked CRU emails tell us?
    Here's what the "decline" looks like: http://akwag.blogspot.com/2009/11/hiding-decline-what-that-really-looks.html
  32. What do the hacked CRU emails tell us?
    I meant to link to a pdf of the Trenberth/Fasullo?Kiehl article in Bull Am Met Soc 2009
  33. What do the hacked CRU emails tell us?
    re #70 billbrent, I think you're discussing a sort of sub-level of uncertainty that lies underlies a broader certainty of understanding. There are (at least) two examples of this in climate science: (i) sea levels. There's rather good evidence that sea levels are rising a bit over 3 mm per year at the moment (highish certainty [*]). This must be the result of some combination of heat accumulation (thermal expansion) and mass increase (polar ice sheet and mountain glacier melt), and the summation should match the observed sea level rise if the "energy budget" is properly "closed"). Each of the latter can be estimated independently; however each of the latter measurements has greater uncertainty than the more easily measured total sea level rise. So there is a sub-level of uncertainty in the precise partitioning of sea level rise within its (less easily measured) components. The greater uncertainty in the latter doesn't negate the lesser uncertainty in the former. (ii) Radiative forcing and it's precise partitioning. This is very similar to (i) but more complex. We have rather good evidence that the net forcing from raised CO2 is equivalent to a warming near 3 oC (plus/minus around 1 oC) per CO2 doubling. The forcing is the result of a radiative imbalance between incoming solar radiation and outgoing longwave IR emitted from the earth's surface. Partitioning this to the components (solar radiation reflected to space; solar radiation reflected by surface; solar radiation absorbed by clouds; surface emitted LWIR; surface LWIR reflected from the atmosphere...and so on)...is very complex (see Figure 1 here [**]). The nett top of the atmosphere radiative imbalance that we can estimate reasonably well from theoretical analysis combined with paleoproxy analysis (that allows us to estimate the expected equilibrium temperature response to doubling CO2), is a small number that results from the summation of many large numbers. So the uncertainty in this summation of many large numbers to give a net TOA forcing has a lot of uncertainty since tiny errors in the large numbers (solar radiation emitted from the earth surface; LWIR absorbed by the atmosphere etc; see Figure 1 [*]) result in large errors in the summed TOA radiative forcing (i.e. "closing the enrgy budget"). However that doesn't mean that we don't have quite a good handle on the estimate of the total radiative forcing from independent analysis. Trenberth's problem (if I am interpreting his email correctly), is that we need to understand the component forcings and their responses if we want to assess whether geoenginering approaches will have any chance of being successful. That makes sense since geoengineering approaches (blast sulphurous aerosols into the atmosphere) affect sub-components of the total radiative forcing (.e. they mostly reduce solar radiaiton reaching the surface, but we need to know by how much before we start pumping the stuff into the atmosphere). [*] http://www.skepticalscience.com/Are-sea-levels-rising.html and: http://www.skepticalscience.com/A-broader-view-of-sea-level-rise.html [**] Trenberth, K. E., J. Fasullo, and J.T. Kiehl, 2000: Earth's Global Energy Budget. Bull. Amer. Met. Soc.. 90, 3, 311-323.
  34. What do the hacked CRU emails tell us?
    I did not make a random selection.
    No, not you, the people who stole the e-mail have published a random selection, and we have no idea as to what's missing or not, or how cherry-picked the published e-mails are.
    I have not misrepresented Trenberth's work in any way.
    Well, Trenberth is on record as saying that the kind of conclusions you draw do misrepresent his work. I'll take his word on it, sorry.
  35. What do the hacked CRU emails tell us?
    Well, I just looked at the Briggs discussion of tree ring proxy reconstructions and, really, it's a cartoon description that really bears little resemblance to reality.
  36. What do the hacked CRU emails tell us?
    dhogaza #67 You wrote: "Can you explain why Trenberth disagrees with your assessment regarding policy to my (or anyone's) satisfaction if your reading of the tea leaves (sorry, "random selection" of purloined e-mail) reflects the level of uncertainty being discussed?" I did not make a random selection. I picked a discussion that reflects my deep concern about the policy implications stemming from climate science being passed off as "settled" when there are disagreements among leading AGW scientists about the physics. I have not misrepresented Trenberth's work in any way. And I don't like tea. As I said in my response to SNRatio (#78), Trenberth's question, "What are the physical processes?" doesn't seem to be "a relatively minor problem" easily explained by the "existing instrumentation isn't sufficient for researchers to close the earth's energy budget during La Niña." I'm not saying Trenberth's concerns mean that the underlying physics are "contradicted," I'm saying that he's indicating that the physics are not completely understood. And the exchange with the other scientists most definitely shows that the physics - the science - is certainly not "settled," which is my biggest concern. You will not find anywhere in what I've written that "maybe global warming doesn't exist."
  37. What do the hacked CRU emails tell us?
    Actually I was talking about the fact that his proxies don't work well for the last ~50 years.
    First of all the proxies aren't "his", he analyzes work by others. But what you're referring to is exactly the "diverenge problem", no secret, openly discussed in the literature, actively discussed in the literature. The problem is only with *some* tree ring proxies, not *all* tree ring proxies, much less non-tree ring proxies. John's going to do a post on it, I suggest postponing discussion until he does.
  38. What do the hacked CRU emails tell us?
    re #11 SNRatio, I agree with much of what you say. However, I’d like to comment on your post re: IPCC projections (you say they haven’t been conservative enough) and models (you suggest that they have been somewhat oversold). Since model output has been around for quite a while now we can compare model projections to real world outcomes. Likewise since the IPCC projections have been around since 1990 these can be compared with real world outcomes. (i) IPCC projections cf real world outcomes. A comparison of IPCC projections since 1990, with real world outcomes through 2006 allows us to assess their accuracy. If one looks at (i) CO2 levels [*] (ii) temperatures [*], (iii) sea level rise [*] (iv) arctic sea ice retreat [**], it’s pretty obvious that the IPCC projections have been conservative. CO2 emissions have followed IPCC projections since 1990 quite closely. Temperatures have risen at a rate that is right at the top end of the IPCC projections. Since this is a short comparison period this might just be the result of natural variation on top of a rising trend. Sea levels have risen much faster that the IPCC projections [*]. Arctic sea ice recession has occurred at a very much faster rate than the IPCC projection [**]. Obviously all of these metrics are for a rather short period (8-18 years). But if a comparison of the important metrics (atmospheric CO2, temperature, sea level, sea ice retreat) are occurring at the upper limits, or outside the upper limit of the IPCC projections, I don’t see how we can say that the IPCC projections aren’t conservative enough. Whether they’ll continue to be conservative into the future remains to be seen (very likely the IPCC sea level projections are conservative since they exclude any “non-linear” contributions from poorly predictable ice sheet dynamic responses). [*] S. Rahmstorf et al. (2007) Recent Climate Observations Compared to Projections Science 316, 709-710 [**] http://www.copenhagendiagnosis.org/download/Copenhagen_Diagnosis_LOW.pdf (ii) Comparison of models with real world outcomes This is more difficult to assess. There’s no question that models outputs have to be treated with caution. However we can compare model projections with real world outcomes. The earliest simulation (and one you comment on) is Hansens’s simulation set up around 1985 and projecting temperatures forward. This simulation has followed reality rather well (it is pretty much spot on through 2005; see Figure 2 here, a freely downloadable paper [***]). You comment that this particular model is parameterized according to a climate sensitivity of around 4 oC (4.2 oC). But this wasn’t so well-defined in the mid 1980’s nearly 25 years go. And the fact that the simulation parameterized according to a 4.2 oC climate sensitivity, matches the real world temperature progression, means that the real world temperature is rising at a rate that is consistent with a rather higher climate sensitivity than the mid range (3 oC). Of course it might not be (too soon to say); but I don’t see that we can say that model outputs are oversold when they match reality quite well… ..and that applies to the model predictions of polar temperature amplification…of water vapour feedback (before this was measured directly, Dr. Lindzen was asserting that tropospheric warming would result in a drying of the upper troposphere – he was shown to be wrong; the models were shown to be right)…of a temperature induced water vapour feedback yielding a close to constant relative humidity….the models predicted the magnitude and temporal response of temperature to the Pinatubo eruption…they predicted a fast Arctic and delayed Antarctic response to global warming…they predicted greater nighttime warming over daytime warming in a greenhouse-warmed world…they predicted a tropospheric warming that was, for about 15 years, asserted to be incompatible with the UAH satellite measure of tropospheric warming, until in 2005 it was shown that a series of systematic errors in the UAH analysis was responsible for the apparent incompatibility….the models were correct again… ..and so on.. ..it’s very easy to be sceptical of models (and we should be!), but they’ve been pretty successful so far. Whether they will continue to be successful into the future remains to be seen. [***] http://www.pnas.org/content/103/39/14288.abstract?sid=30711dcf-c67f-48ba-8983-f775d6a54d3f
  39. What do the hacked CRU emails tell us?
    re #55 sorry, mate...what people write or say in magazines, newsletters, newspapers, and so on is not necessarily scientifically sound nor even necessarily science. Ollier has published proper papers in the scientific literature. The stuff you refer to isn't. The whole point of publishing in the scientific literature is that it forces a degree of scientific rigour on the measurement, analysis and presentation of the data, and that it becomes part of the scientific record to be built upon, referred to, contradicted (or sink into oblivion). If Ollier discovers something worth publishing in the scientific literature, no doubt he'll do so. (Incidentally I made a small disservice to Ollier - his last paper wasn't 2007 - he published a paper in 2008 on Deccan duricrusts, which is nothing to do with sea levels of course. He hasn't published a scientific paper in 2009 so far.) Nope Morner's comments aren't relevant. They're from some interview on some web site. We know how sea level measures are made. There's dozens of papers on this. A recent update of the subject can be found on the links to pages on this site [*]. If Morner has some problem with this he should publish on it rather than sniping in interviews. It's not scientifically interesting since it seems not to accord with the science. [*] http://www.skepticalscience.com/Are-sea-levels-rising.html and: http://www.skepticalscience.com/A-broader-view-of-sea-level-rise.html Incidentally, I wonder if you would really be happy in the world that you seem to want to inhabit, neilperth? Where you decide what seems like an expedient course of action that suits a particular political point of view, and then propagandise for this for all your worth. You might be comfortable in a world where "science" was "decided" by propagandising bullies, but you might find that their agenda didn't always match yours! To my mind, we're extraordinarily fortunate that we live in a world where a degree of independent scientific rationality exists, so that we aren't at the whim of those that consider it expedient to pervert the science on the toxicity of tetraethyl lead (say), or the role of cigarette smoking in lung cancer, or the dangers of aspirin taking in children with respect to Reyes syndrome, or the effects of CFC's on stratospheric ozone...and so on (a long litany of anti-science propagandising on behalf of vested interests). The science has pretty much always been right on these things...not sure why you think the science of the greenhouse effect is any different. I expect we'll find that the scientific understanding that develops from careful and independent thinking, researching, measuring, interpreting, synthesizing and publishing in the scientific literature is still going to be a better route to understanding, than random assertions from website interviews or articles in newsletters.
  40. What do the hacked CRU emails tell us?
    SNRatio #57 You wrote, "Why don't you check the facts before jumping to conclusions? And with explanations easily available, your reference to and interpretation of the notorious "Mike's Nature trick" either shows an ignorance I would not expect from contributors to this site, or willfull misrepresentation." Why don't you read my post more carefully. I did not say one word about "Mike's Nature trick"! I don't have a problem with the term "trick" being used, especially without a better understanding of the context. I know mathematics and science are full of "tricks" to accomplish certain tasks. Plus, I'm not a "contributor" to the site - as in a professional scientist - I'm a commenter. I stated up front that I was a layman. When you finally did address my question, you take issue with my "sweeping statement" that there is a "very serious disagreement" about the physics. I'll grant your point that I don't know all the details and so perhaps shouldn't have used the modifiers "very serious." But there is an undeniable disagreement about the physics that doesn't seem to be easily explained with "it's more about the lack of data," or Trenberth's higher standards. Trenberth asks, "What are the physical processes? Where did the heat go?" These questions are not simply answered with more data, are they? Aren't they more about a fundamental physical understanding? I deeply appreciate that you are willing to state that "the models are not adequate, and they have to be improved." And that you are "concerned that the results may have been oversold." That is my concern as well. And I must say, this is not a small thing. In a world where the primary motivator in journalism is, "If it bleeds it leads," and the most sensational stories make the front pages, and those stories motivate policy makers to pass legislation that can constrict individual choices and freedom, I think honest scientists need to shout those concerns to the heavens. So, again, your honesty in this regard is deeply appreciated. You wrote, "The positive feedbacks, while still very significant, have been smaller than implied by the models, and now they are looking into why." Recently, Prof. Lindzen wrote that the satellite data is showing that the feedback is actually negative. Are you familiar with that argument? And can you argue for or against it? Also, there seems to be some thought that the large quantities of SO2 being pumped into the atmosphere in India and China is having a moderating effect on the greenhouse effect of CO2. Could that be the case? Thanks for addressing the issue of social engineering. You wrote, "even with zero positive feedback, "carbon liberalism" will get us into climate problems pretty soon." But with zero positive feedback, won't we get only 1 degree C rise in average global temperature with every doubling of CO2? And even with the accelerating CO2 emissions of India and China, won't that doubling take tens of years? And has there been adequate study of CO2 sequestration by additional plant growth to warrant the severe GHG restrictions currently being discussed?
  41. What do the hacked CRU emails tell us?
    dhogaza:The only proxy I imagine you might be talking about was the lake bed proxy from Finland which McIntyre et al trumpet "was used upside down!". Actually I was talking about the fact that his proxies don't work well for the last ~50 years. IAC, here is a pretty good overview of proxy reconstruction issues IMO: http://wmbriggs.com/blog/?p=1362#comments "Meanwhile - the CO2 science site is thoroughly unreliable as a source of objective information. My saying so probably won't convince you, but it needs saying." Well, perhaps, but it references dozens of peer-reviewed papers. Personally, my view is pretty much in line with Briggs above, so I don't put too much faith in any reconstruction. FYI, here is a reconstruction that differs from the mainstream ones. http://www.ncasi.org/publications/Detail.aspx?id=3025 My point here is that there is substantial difference in the reconstructions depending on how they are done(this makes confirmation bias a problem IMO no matter how you reconstruct temperatures). Cheers, :)
  42. The albedo effect
    So in what paper specifically will I get the answer to my question: If carbon dioxide traps infra red radiation from earth (keeping us warm) then it must follow that carbon dioxide also shields us from the sun (similar to ozone blocking UV and water vapor blocking IR). So what is the nett effect, especially at the relevant levels of carbon dioxide of 0.02% – 0.05%? If you think it is so easy to get an asnwer to my question, why not just give it to me? I have been searching for months, and I did not get it.
  43. The albedo effect
    Oh nice, "hidden in a published paper". It's called an oxymoron.
  44. What do the hacked CRU emails tell us?
    Models are still, for all their apparent sophistication, unable to include many known factors that influence climate..a fact that is acknowledged by the modellers...
    Please name the *known* factors which models are unable to include. I'd appreciate your using your own words. Thank you.
  45. What do the hacked CRU emails tell us?
    Yes, I've read a bit. It seems to me that people have logical seeming reasons for why they choose the proxies they do, whether they actually are good proxies is another question.
    Yes, of course, that's why a variety of proxies are compared and why paleoclimatologists don't hang their hat on a single one. Compare that with how, say, McIntyre works - "Yamal! Yamal! Yamal!" - as though chipping away (ignorantly, IMO) at one proxy will make them all disappear.
    Mann's proxies seemed logical to him until we found that they don't work under certain conditions.
    The only proxy I imagine you might be talking about was the lake bed proxy from Finland which McIntyre et al trumpet "was used upside down!". Here's an interesting fact: Mann's paper stated clearly and upfront that it was though there might be problems with that proxy. Therefore he checked for robustness of his multi-proxy reconstruction with and *without* the questionable proxy. And got virtually the same result. The denialist screams about "upside down proxies!" very cleverly for the most part fail to mention that Mann himself was the first to state potential problems with the proxy, and most especially tend to ignore the fact that he tested for robustness without the proxy in question. Yet this is the proxy that is claimed "breaks the hockey stick!" and "breaks Mannian science", etc.
    IAC, I admit to not being that up to date on the issue, perhaps you can help me resolve this question by pointing to some research where the proxies match reasonably well for both the long-term reconstruction and the current temps.
    About a month ago I found a really great overview paper (probably prepared as background material for a college course or seminar) by googling. Unfortunately, I've tried several times in the last couple of days to find it again, without success. I'll try to spend more time being clever in google to see if I can find it again, and if so, will post a reference. Meanwhile - the CO2 science site is thoroughly unreliable as a source of objective information. My saying so probably won't convince you, but it needs saying.
  46. What do the hacked CRU emails tell us?
    #73: No, we need to acertain what the risk is before embarking on 'corrective action' which could conceivably cause more harm than good. We do not know enough and do not yet have adequate models or computing power to do more than make rough assessments. Climate change will occur whether or not we modify our output of CO2, to what extent we still do not know with any exactitude that enables us to make 'proper' decisions. Models are still, for all their apparent sophistication, unable to include many known factors that influence climate..a fact that is acknowledged by the modellers...but unfortunately not by the politicos and eco-warriors. I readily accept much of the science underpinning AGW, but I do not accept the output of the models which include so many assumptions that IMO they are pretty worthless. ( I await the deluge ).
  47. The albedo effect
    Henry, those papers are not "hidden." They are published in journals. Publicly. That's the point of "publishing." That's what "published" means. That blurb about none of the articles being available on line is left over from when the list was first started. Now many of the articles are available on line, and some even for free. If you go to the trouble to actually click on the links that are the titles of the articles, you will be able to see for yourself whether the full articles are available on line. In fact, the very first one on the list (Toth et al. 2008) is in fact available on line for free--the full text, both in HTML and PDF. If the full article is not available for free on line, often you can still get it on line by spending just a little money. Or you can get any of those articles for free by getting out of your armchair and going to a library to look at the paper versions. If you don't have a university library nearby, your local public library can get copies of the articles for you.
  48. The albedo effect
    Tom, here is the quote from your "list" "This is a list of papers on laboratory measurements of the absorption properties of carbon dioxide. In the context of these paperlists this is a difficult subject because none of the papers seems to be freely available online, so we have to settle on abstracts only. However, I don’t think that matters that much because the main point of this list really is to show that the basic research on the subject exists. The list is not complete, and will most likely be updated in the future in order to make it more thorough and more representative." Now go back to see what I wrote in 74: As Weart told me some time ago: you cannot see the evidence because the wise men have decided to hide it in papers that cannot be accessed. If it is so difficult to explain as to how the tests were done that proves that those 70 ppm's of CO2 added since 1960 are significant, how can we expect non-scientists to make the right decisions in Copenhagen? I am not interested in abstracts. I want to see the results and how the tests were done... how much heat retention is caused by 100, 200, 300, 400 ppm etc. and you will find that such results do not exist because you cannot measure anything relevant at those concentrations of CO2. To extraolate results from high concentrations back to lower concentrations is the wrong type of science. Properties change at different conc. levels. You must always measure at the relevant concentrations. In addition, no one seemed to have realised that CO2 causes cooling (reflection of sunlight) as well as trapping of earth's radiation. So you have to take that into account in your testing method as well.
  49. East Antarctica is now losing ice
    Just to add a bit of context... Antarctica is estimated to contain some 30 x 10E6 km3 of ice; about 10,000 years worth at current rate of melt. Antartic climate is subject to high inter-annual variabilty as indicated in Ferron et al 2004 which shows steep temp rises over very short time scales in the past. As with the Greenland ice sheet, melt/calving is mostly at the edges since inland air temps are far too low to allow melt. Equally, inland precipitation is generally low for the same reason. It seems logical to me that the increase in ice loss is due to changes in sea temperatures and circulation, with possible correlation to PDO and similar southern ocean cycles. Also intersting to note that the GRACE pic shows noticeable anomalies around 0 degrees.....??
  50. What do the hacked CRU emails tell us?
    People, how much time do you think we have to quabble about some academic infighting at one research outfit? The longer we argue about minutia, the longer we wait to act based on the broad body of supporting evidence from around the world, the more difficult it will be to mitigate the risk that climate change presents. And why are skeptics so quick to criticize some climate scientists for unethical behavior, yet they readily accept a few ideas or findings, often involving similar unethical practices, from the few dissenting scientists that remain? They are probably heavily biased themselves, due to a rigid belief system, financial motivations, or otherwise. We need to move forward with the more relevant discussion asking "To what degree should we mitigate the risk, using what methods, and how will we pay for it?" Anything else is just a waste of precious TIME.

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