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Comments 126301 to 126350:

  1. The albedo effect
    Oh nice, "hidden in a published paper". It's called an oxymoron.
  2. 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.
  3. 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.
  4. 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 ).
  5. 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.
  6. 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.
  7. 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.....??
  8. 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.
  9. What do the hacked CRU emails tell us?
    dhogaza:"Have you read anything on how, for instance, tree ring chronologies are chosen for temperature proxy work? It's not based on "confirmation bias" based on recent warming, but rather on site characteristics and ring morphology that reflects known temperature signatures in tree ring tissue based on knowledge of tree physiology." 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. Mann's proxies seemed logical to him until we found that they don't work under certain conditions. CO2science.org lists quite a few different proxy studies(that I'm sure the authors believed were properly chosen). 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. Cheers, :)
  10. What do the hacked CRU emails tell us?
    5) CO2 in reality is coming from warming and de-pressurizing sea water, all year round, and from the deep sedimentary basins in the northern spring
    Hey, Peter, that's very interesting. But I'm wondering ... where is all the CO2 produced by our burning of fossil fuels going?
  11. What do the hacked CRU emails tell us?
    Just to make it clear: I do not defend their approach to the divergence problem in that case, in particular their presentation.
    Not "their", but one person, and in the case under discussion, one graph which appeared in one brochure put together by the WMO. In the published literature, the "divergence problem" is, of course, openly discussed (it is scientists in the field who coined the term in the first place), comparisons of reconstructions with and without the troublesome recent decades made, comparisons to the instrumental record made, etc etc. If the divergence problem were being "hidden", etc, denialists wouldn't know about it and wouldn't've been screaming about it for years. Denialists only know about it because it's a well-known issue in the field, not because they've recently read some stolen e-mail messages.
  12. What do the hacked CRU emails tell us?
    This isn't science, its arranging data to suit a pre- conceived agenda
    Yeah, the "preconceived agenda" which is ... hmmm ... let me think: The instrumental (thermometer) record is more reliable that tree ring proxies, and when they conflict, the direct measurement is preferable to the indirect proxy. Some agenda. Some conspiracy.
  13. What do the hacked CRU emails tell us?
    I'm sorry, but it is not true that the inaccuracy of the proxy data within about 0.5C of current temps has nothing to do with the MWP. Many points during the MWP had similar proxy values to the post 1961 values. (http://www.21st-century-citizen.com/Hockey_stick_chart_ipcc1.jpg) If the post 1961 proxy values can mean that temperatures are as high(or higher) than current ones, then obviously it is *possible* that MWP temps were also as high (or higher) than currently. Also, it bears mentioning that it does not follow necessarily that a warmer MWP means that feedback is higher, it is also possible that forcing was higher than our current estimates allow for. Cheers, :)
  14. What do the hacked CRU emails tell us?
    John, this is a very serious disagreement over the physics of planetary warming, or lack thereof over the last few years. It has the potential to profoundly impact policy-makers decisions. Can you explain the physics to Trenberth's satisfaction?
    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? As Ternberth himself complains, his scientific work is being misrepresented by the denialist camp. A relatively minor problem - existing instrumentation isn't sufficient for researchers to close the earth's energy budget during La Niña (the cooling he's talking about) - is being misrepresented as somehow contradicting the underlying physics or the basic fact that the earth is experiencing a long-term statistically significant warming trend. "We don't precisely understand the physics of how La Niña shuffles energy around" does not translate into "maybe global warming doesn't exist", etc.
  15. What do the hacked CRU emails tell us?
    "Objectively" chosen or not, temperature reconstructions being what they are, it is virtually unavoidable to separate measurements into the ones that reflect a real temperature signal and those that do not. You have to make some assumptions one way or the other. If you already know what the "correct" answer is, it is human nature(at least IMO) to be more likely to reproduce that answer again.
    Have you read anything on how, for instance, tree ring chronologies are chosen for temperature proxy work? It's not based on "confirmation bias" based on recent warming, but rather on site characteristics and ring morphology that reflects known temperature signatures in tree ring tissue based on knowledge of tree physiology. The confirmation bias, I guess, would be the assumption that trees today grow very much like trees did a thousand or two years ago. The weakest assumption - acknowledged in the literature - is that the single most significant limitation on growth is likely to remain the same for long periods of time at a single site. The basis for this assumption, I imagine, is that the "long" timescales they're looking - one or two thousand years, say - are just a blink of an eye geologically. But that's not "confirmation bias" as you're speaking of it. Really, go read, don't speculate. I spent a day reading up on the dendro/temperature proxy stuff - reading intelligently (i.e. ignoring McIntyre, jeff Id, and the like in favor of scientific sources of information) - and was able to learn quite a bit. Enough to know you're just speculating.
  16. Record high temperatures versus record lows
    Albatross, thanks for the info. Do you recommend anywhere to look regarding background on lightning and land-atmosphere feedbacks?
  17. What do the hacked CRU emails tell us?
    To date, there has not been a single credible journal article that shows a natural cause for the modern day warming while also showing how record high greenhouse gas concentrations are not significant. NOT ONE. Do people really believe that the scientists at CRU are able to squelch every scientist on the planet who tried to publish this landmark anti-AGW paper? Is there no sense of the low probability and the large scale of this conspiracy for this to be true? If one throws out the HadCRU data and all papers by these folks, there is still a mountain of evidence for AGW. Do the rapidly melting ice sheets and glaciers have access to these emails and joined in on the conspiracy? Do the various climate models that show GHGs as the dominant forcing mechanism have access to these emails and joined in on the conspiracy? Do the GISS, UAH, RSS data have access to these emails and joined in on the conspiracy? Certainly Spencer and Christy would not align themselves with AGW and yet their satellite-derived measurements track reasonably with GISS, RSS, and HadCRU. Does the ocean read these emails and magically increase its heat content? Does the cooling stratosphere (even accounting for ozone loss) read the emails and join in on the hoax? Do the plants and animals read these emails and decide to die off and/or change their migratory habits so that they can support the conspiracy? I could go on ad infinitum. For quite a long time, we have known that a doubling of CO2 will warm the climate at least 1C and there is fairly good certainty that the resulting feedbacks will produce at least 2C additional warming with 3C more likely. We are also measuring CO2 increases of 2 ppm and climbing (except last year where there was a slight decrease due to the global recession) and we have levels that have not been seen in the past 15 million years. Are we to conclude that these emails deny all of this evidence? It is obvious that pre-Copenhagen, the tried and true method of “if one does not like the message then attack the messenger or redirect the conversation” practiced by Big Tobacco and now Big Oil and their front groups (Heartland Institute, George C. Marshall Institute, Competitive Enterprise Institute, etc.) is alive and well. Scott A. Mandia – Professor, Meteorologist, Concerned Citizen http://www2.sunysuffolk.edu/mandias/global_warming/
  18. Water vapor is the most powerful greenhouse gas
    For one: The reason "I don't know enough to argue in any specialized field" is quite simple due to the fact that next to the majority of what is to be read is not worth it. A lot of it is in my view often stating trivialities cloaked on science language. On the other hand by far too often statements are made that can't stand any initial logical evaluation. Let's take as an example for the latter the wikipedia article on water vapor you referred to. Now let's just take a look at the paragraph on Condensation. I will include my comments in lines starting by the usual comment sign known from programming # continued citation will be marked with an >. It states: Water vapor will only condense onto another surface when that surface is cooler than the dew point temperature, or when the water vapor equilibrium in air has been exceeded. When water vapor condenses onto a surface, a net warming occurs on that surface. # not necessary because that would depend on the ability of that surface to hold additional heat (energy). > The water molecule brings a parcel of heat with it. # why referring here at molecules when this amount is given in the properties section as 2.27 MJ/kg. I'm too lazy to look up what that would make in watts but I'm pretty sure we are talking about real energy here and not some negligible portion as indicated by the term parcel. >In turn, the temperature of the atmosphere drops slightly. # That is absolute nonsense it implies that the surface it condenses to absorbs more energy (heat) than is set free in the process. > In the atmosphere, condensation produces clouds, fog and precipitation (usually only when facilitated by cloud condensation nuclei). # Does that mean when taking place in the atmosphere no energy (heat) is released at all or maybe absorbed by the condensation nuclei? That would be a rather absurd notion and to my knowledge contradict the first law of thermodynamics. ># I canceled the rest of the paragraph. So far so well (or not so well). I hope this made a bit more clear what I mean when speaking of "not knowing enough". Now, this is what happens in my view: Given the right conditions water evaporates mainly near the earth surface. Due to it's density it then starts a path to higher altitudes. If then again the conditions are right it condenses and continues it's route until at last it comes down again as rain, snow or hail. In the process of evaporating the amount of 2.27 MJ/kg of energy is used. Logic dictates that the same amount has to be released at condensation. I hardly dare saying that it should be obvious that at the point where condensation occurs it's getting warmer. Now given the fact that on average water stays only 10 days in the atmosphere this is a real fast process. Now I'd like to know if you can find something wrong in this statement. Anyway it would prove a better starting point for a real discussion because it is more suitable to uncover differences in the understanding of the basic principles.
  19. The albedo effect
    Henry, I already answered your #75 in my comment #69. Extra water vapor "added by humans" includes water evaporating from human-created pools.
  20. The albedo effect
    Henry (#74), I answered your #68 question already in my #55. But apparently you stopped reading before you got to my last paragraph, where I pointed you to a list of scientific papers reporting on experiments that systematically varied the concentration of CO2, and other parameters, and measured the effects. Those empirical results, and others, have been built into a graphical computer program by David and Jeremy Archer, that you can run to see the effects of varying concentrations of CO2, water vapor, and other factors, in the transmission of radiation through the Earth's atmosphere.
  21. The albedo effect
    @Tom at 72 There is an important point that you forgot. As we have discussed much earlier in this subject, one of the reasons that the earth's albedo increased, is (probably) because of increased human activities concerning the creation of shallow waters (dams). This is water for human consumption and irrigation. This water heats up (easily, because it is shallow)), and water vapor is created. This traps the heat coming from earth. This is what is definitely not counted in AHF?
  22. What do the hacked CRU emails tell us?
    What worries me most is the science discussions suddenly turn into politicized discussions where pro- and contra- arguments fly across the table. There is no need for a contra AGW discussion, the CRU data hack didn't change the discussion at all, because man made global warming is widely accepted despite the fact that real data are added back in.
  23. What do the hacked CRU emails tell us?
    To neilperth I seem to agree with every word you say. No changes.
  24. What do the hacked CRU emails tell us?
    John, It is clear that skeptics are the badguys. But when they ask, "OK, so if CO2 is the culprit, what alternative do you propose? And what are the risks of these solutions?", all that you find on this website is the same churning about CO2, CO2, CO2. Where is the science that points to solutions and alternatives??? Whether global warming is manmade or not should have no relevance if the alternatives are so attractive and have no "risks". Please explain.
  25. What do the hacked CRU emails tell us?
    Regarding your response above, my reply is as follows : It is clear from some of the hacked Hadcrut emails that the climate research scientists agree that they do not understand why there is a lack of warming at present and that their computer models do not predict this lack of warming. There are also emails which state that when climate changes, it is often difficult to apportion the cause ( man-made, natural or some combination of the two. ) Your statment above : "there is a greater than 90% chance that humans are causing global warming" is not correct is it ? It should read : "there is a greater than 90% chance that humans are having some effect on global warming - but natural forcings still play an important part" In any event, given the many factors that go into any estimate of probability in this case, I would not take the scientists 90% chance claim seriously in terms of a statistiacl probability. I believe that in the IPCC reports this probability is expressed as more of a "gut feel" rather than a statistically calculated probability. If all the uncertainties are taken into account, each with its associated confidence interval, I would be amazed if the result would be a 90% probability. If this 90% chance was based on a statistical calculation, do you have the complete data sets used as I would like to see them? Many (most ?) skeptics ( including myself ) are not anti AGW or anti environment. I would say that most (?) of us would agree that the temperature is rising in general and would agree that trying to curb toxic emmissions is good. What I cannot abide is the fact that the way of doing this ( carbon tax, possible " world government", passing billions of dollars over to third world countries etc ) is the wrong way. It is clear that this scenario would be based on very shaky science and one would have to be naive not to realise that such a decision would be motivated by wider political considerations.
    Response: You're putting the horse before the cart. Carbon taxes and one world governments have nothing to do with climate science. The confusion and muddled thinking that occurs when politics are inserted into climate debates are the reason why this website is concerned with a single question - are we causing global warming? The answer to that question lies purely in the realm of science and empirical measurements. I would encourage you to clear your head of one world governments for the moment and consider what observed empirical data has to say about man's influence on climate.
  26. CO2 effect is saturated
    i thought venus's atmospheric pressure has a lot to do with its temperature?
  27. It's cooling
    i'm new to this and i'm a skeptic. however, i'll admit that the planet is still warming. using satellite data from UAH and RSS, if you look at the past decade or so including 1998, it shows a cooling trend. however, if you remove the 1998 el nino freak year, the planet is still warming at a similar rate to pre-1998.
  28. CO2 is not the only driver of climate
    commenting on IPCC radiative forcing diagram: gee...so many anthropogenic causes and just one natural variable? does that seem a little biased? has the IPCC really investigated all the variables, or did they decide that humans were the cause before the investigation?
  29. What do the hacked CRU emails tell us?
    For me, what comes out of the hacked Hadcrut emails is that there is much disagreement between scientists about many aspects of climate research, particularly in the area of interpretation of proxy data. That is tree-rings, ice cores, lake sediments etc. One email states that it is generally considered by scientists that the effect of the solar cycle cannot be identified in the temperature record. The same scientist then does some research and comes to the conclusion himself that effect of the solar cycle can be identified in the temperature record. My point is that the emails show that there are large uncertainties in the field of climate research. But it seems we have not been told this. We are instead told that the science is settled. It is not ! And now world governments want to spend hundreds of billions of dollars fighting this global warming (or is it climate change ? ) based on such shaky science.
    Response: Certain key questions are settled. The warming effect from CO2 is known with high understanding and directly observed by satellites and surface measurements. The planet's energy imbalance is directly measured from ocean heat and satellites. There are other areas with higher uncertainty such as the radiative effects from aerosols or the behaviour of clouds as climate warms. When all the uncertainties are considered, climate scientists conclude that there is a greater than 90% chance that humans are causing global warming (I believe this actually understates the certainty).

    If you were told there was a greater than 90% chance that a plane was going to crash, would you get on board with your family? And yet this is the risk skeptics are happy to take with the planet we're handing over to our children and grandchildren.
  30. What do the hacked CRU emails tell us?
    re: divergence problem 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. If I have 10 clocks in my house and I notice that one of them starts working: 1) I know that it is more likely that one clock is giving the wrong reading than the other 9 showing the same wrong reading. 2) It would be silly to criticize me for not using the errant clock when its clearly wrong. It is neither devious nor underhanded to avoid the bad clock. I have to admit that I thought the CRU leak was going to be a big deal. After reading through it and reading the explanations given I am surprised that so little of substance can be used to criticize the team. I do think as a PR issue they should make a statement which will clear the air and also serve as a scary science lessen for those that think AGW is a hoax.
  31. The albedo effect
    I note that nobody answered me directly on 68! Steve, nobody has shown to me in an experiment what the influence is of 70 ppm's of CO2 that were added to the atmosphere since 1960. The formiula's and the values for the forcings for CO2 concentrations just fall out of the air somewhere (no pun intended). 1.7 has been mentioned. Tom talks about 2.6. Riccardo even has a formula. I just don't know where those vales come from. I want to see experiments and meaurements, not proportional blame that the IPCC has decided upon/ based on comparisons to concentrations back to as far the year 1750. If it is so easy for you, why not just explain to me how the experiments were done? I asked you to comment on 68 and you did not. I am saying: whatever is causing global warming (if it still happens) my conclusion from whatever "evidence" I have seen so far is that it is not caused by CO2. 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 are significant, how can we expect non-scientists to make the right decisions in Copenhagen?
  32. What do the hacked CRU emails tell us?
    @billbrent, 54 "John, this is a very serious disagreement over the physics of planetary warming, or lack thereof over the last few years. It has the potential to profoundly impact policy-makers decisions. Can you explain the physics to Trenberth's satisfaction? Or to the satisfaction of the average layman - like myself - who is concerned about the social engineering being proposed based on this very physics? " 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. Just to make it clear: I do not defend their approach to the divergence problem in that case, in particular their presentation. But it's not fraud to proceed as they do. And it's not about the benefit of doubt here, the wording uses "trick" as in my favorite definition of "method": "A method is a trick that you use twice." Any attempt at a fair interpretation would show up this. And no, it is NOT a fair interpretation to pick one that implies malpractice without checking alternatives first, even if that one comes easily to mind. Then, to "very serious disagreement over the physics of planetary warming". You did check all the details before you make such a sweeping statement, didn't you? Oh no, then you wouldn't used that wording. First, the "balancing of the energy budget" is according to Trenberth's standards, and they are higher than average, to say the least. Second, this is mostly not about lack of physical understanding, but lack of data. The observations show that the models are not adequate, and they have to be improved. Which is not shocking unless you have had very much faith in the present incarnations of the models - and that may be the case with some in the general public. I'm concerned that the results may have been oversold. But the focus on this blog is on the science, and there is really nothing new or very problematic in what Trenberth is talking about. To get us where he wants may very well imply some methodological revolutions, but almost surely none of physics. To put it simple: The positive feedbacks, while still very significant, have been smaller than implied by the models, and now they are looking into why. Your concern about "social engineering" is valid. But to me, it's a bit the other way around: Increasing the GHG emissions as we do is a gigantic, for a large part non-reversible, experiment, and THAT should not be allowed unless we know the consequences fairly exactly, and there is global agreement that they are acceptable. We know, both from theory and observations, that anthropogenic global warming occurs, the question is about the extent. And, contrary to what many "skeptics" maintain, that question is not that relevant to decide about regulations of GHG emissions. Why? First, even with zero positive feedback, "carbon liberalism" will get us into climate problems pretty soon. Second, even with small temperature changes, CO2 emissions will, sooner or later, lead to catstrophic acidification of the oceans. I might add a third: Sooner or later, we have to get off the fossile fuel hook anyway. And why not sooner, when we, basically, already have the technology? But that's not something we should focus on here, I think.
  33. What do the hacked CRU emails tell us?
    "I've just completed Mike's Nature trick of adding in the real temps to each series for the last 20 years (ie from 1981 onwards) and from 1961 for Keith's to hide the decline." This isn't science, its arranging data to suit a pre- conceived agenda. And your stubborn refusal to acknowledge this, and the way you skip over this basic fact shows you are simply protecting the interests of your class-ie mainstream academia. This is a very common human trait, but it is not a scientific one. And its the very reason skeptics are so skeptical-its not about some 'nefarious conspiracy', its simply about human bias and the very common, but unscientific trait, of protecting ones social group/class interests. This is enough to distort data, and to allow it to go uncorrected/unregulated. Take a long hard look at what is being done in the above quote to the actual data, and just as importantly, to its presentation. A basic tenet of science is that the present is the key to the past. This is violated in the above 'trick', 'hiding', 'data handling techniques available in the peer reviewed literature' or whatever you want to call it. Fudging is fudging. The researchers choose to ignore the current, verifiable, tree ring data which shows the technique has major problems with the present, and yet use this same flawed technique to reconstruct the variable and dynamic climatic past, without due reference. They recognise, selectively, that the 'present' has a problem, and so they, conveniently, replace it with something else, but if they are to be consistent they shouldn't then be using the same, verifiably flawed technique, to reconstruct (ie 'arrange') the past. (He who controls history controls the future). This is a selective arrangement to suit ones pre-conceived agenda. They then further violate basic statistical presentation by splicing different datasets, and different methodologies, together, without proper referencing. Every one of these steps violates standard scientific principles. 'Data handling techniques available in the peer reviewed literature' my arse. It is misleading, at best, and wrong at worst, to present spliced data as a single dataset, especially if there are known and obvious flaws in any of the techniques used to obtain parts of the dataset, which are not then applied to the rest of the dataset, and not being properly referenced. Do you really think, that the Busang-like graph of Mann et al 1998 presented to the uniformed public (who are not aware of the splicing etc) does service to science? I don't. The point with the Busang fraud, was that they used spliced datasets which contained flawed collecting (salting) and analysing (eg non-duplicated) techniques within parts of the datasets, and then presented this as a single, coherant (pre-arranged outcome) dataset. This sort of 'hiding' and 'trick' and 'data handling technique available in the peer reviewed literature' cost billions of dollars. Sound familiar to Mann et al 1998? PS. Applying the 'present as the key to the past' to the "suggestion of a change in the sensitivity of tree growth to temperature in recent decades" implies that tree ring growth during abnormally warmer periods is inhibited, therefore further implying a strong MWP which is not being picked up the tree ring proxies-which is the exact opposite to the conclusions of Mann et al 1998, (because he doesn't use this basic scientific tenet, he simply replaces it with a pre-conceived agenda). Moreover both the Wilmking and Briffa papers refer to the 'divergence problem' as real, not as a statistical methodological problem; they don't attempt to 'trick' 'hide' or substitute it with 'data handling techniques available in the peer reviewed literature' to get a pre-arranged outcome, but rather they seek to highlight the connotations of such a divergence (which as I said above, includes a stronger MWP). Your references to the 'physical realities currently being observed' doesn't change the central issue, whether or not these 'physical realities' are being caused by humans (AGW). Th reason the skeptics focus on eg reconstructions, is that this is one particularly sensitive piece of the puzzle which has a large say in whether humans are causing the current warming. I for one, can agree, with a shove and a push, that all your 'physical realities' may well be true, yet the issue of whether humans are causing them remains, and so we go back to eg Mann et al 1998 and his 'tricks' 'hiding' etc. I disagree therefore that such things are only a small piece of the puzzle.
    Response: The divergence problem is not about obtaining a pre-conceived result - it's about compiling all the different pieces of the puzzle into a single, coherent picture.

    The divergence problem has no connection to the Medieval Warming Period - it is concerned with the last few decades of proxy records. But even if the MWP was much greater than currently thought, that would mean climate is more sensitive than currently thought - which means climate is more sensitive to the radiative forcing from CO2. This is the great irony in the skeptic obsession with the hockey stick. If climate scientists have been underestimating past climate change as skeptics claim, then the danger of CO2 warming is that much worse now.

    The "hockey stick" is not a particularly significant part of the evidence that humans are causing warming. It's suggestive, sure, that CO2 and temperature both show hockey stick like shapes. But correlation does not necessarily prove causation. The evidence that humans are causing global warming is found in observations of an enhanced greenhouse effect at CO2 wavelengths.

    If you can be pushed and shoved to agree that the physical realities (of accelerating ice loss in Antarctica, Greenland, glaciers, Arctic, etc) are actually happening, well, each journey begins with a single step. :-)
  34. High CO2 in the past, Part 2
    Fair enough. One last question on this topic. Royer's forcing calculations assume the solar constant to be 5.5% lower than today at the beginning of the Phanerozoic, and that it increased linearly until now. I was not able to find a citation for this assumption. Is this number just so broadly accepted that no citation is necessary? Where did the number come from. The site mentions 4%. Is the 5.5% assumed by Royer, and the 4% mentioned by the site author relevant?
    Response: A good question. I actually wondered this myself back when I first wrote this post and emailed Dr Royer asking the same question. He clarified that the solar levels were calculated in Crowley, T.J., 2000a. Carbon dioxide and Phanerozoic climate. In: Huber, B.T., MacLeod, K.G., Wing, S.L. (Eds.), Warm Climates in Earth History. Cambridge University Press, Cambridge, pp. 425–444.

    The ~4% value applies to the late Ordovician, the 5.5% to the beginning of the Phanerozoic. The article above gives an overview of geological time scales.
  35. High CO2 in the past, Part 2
    Thanks guys. I've read the paper carefully 2 times. I still have reservations regarding the conclusions when I look at the data at face value. I appreciate the efforts and tone on this site. I'll maintain an objective view, and as I learn more, maybe it will all become as obvious to me as it is to you guys. I'll read the paper again, maybe I missed something.
    Response: Your approach is much appreciated. Your question "Will higher anthropogenic CO2 substantially contribute to warming, or are we all just spectators to forces bigger than us?" is answered at CO2 is not the only driver of climate. It explains that there are many drivers of climate - basically anything that causes an energy imbalance. This can be the sun getting hotter, volcanic eruptions increasing the planet's albedo or more greenhouse gases trapping outgoing infrared radiation. Climate scientists have calculated the energy imbalance (otherwise known as radiative forcing) from many different causes and found that the effect from increasing CO2 is not only the most dominant forcing, it also is increasing faster than any other forcing.

    We are not just spectators - we are having an impact that is greater than the natural drivers of climate. This is why climate scientists talk about CO2 so much. It's not because CO2 is the only driver of climate. It's because CO2 is increasing so quickly, it's having a greater impact than other effects.

    That CO2 is not the only driver of climate is important to keep in mind when considering past climate change when CO2 was much greater than current levels. You need to take into account other factors like changing solar levels. When you add up the various factors to calculate the net energy imbalance, what we observe in the past is consistent with our understanding of the CO2 greenhouse effect.
  36. What do the hacked CRU emails tell us?
    Chris .... "New concepts in global tectonics" thought Ollier's paper worthy of publication and as you are no doubt aware, if you want to criticise it, you should address the science he puts forward . On the question of sea level rise, surely you would be concerned about Morner’s comments ( see my previous post ) that the IPCC adjusted sea level data “otherwise we would not have gotten any trend”. Or is that not relevant ?
  37. What do the hacked CRU emails tell us?
    John, You start the comments by saying, "...let me know when they find the e-mails that show our understanding of the physics is wrong." I cannot point to an email that shows that your understanding of the physics is wrong, but it has long been claimed by AGW scientists that "...the science is settled." This claim is used by policy-makers of many countries to promote drastic cap-&-trade-type measures that many see as draconian (if not outright totalitarian). Therefore, while I can't point to an email that shows that the physics is definitely wrong, I can certainly point out an email string that shows the physics is not settled, and indicates that it might be wrong. This exchange - http://tinyurl.com/yl5wz78 - between Kevin Trenberth, Michael Mann, Tom Wigley, Stephen Schneider, and one of Schneider's PhD candidates (read from the bottom, up) certainly indicates that the physics of where the heat went in that past decade is not well understood. Trenberth writes, "...we can't account for the lack of warming at the moment and it is a travesty that we can't." Wigley responds, "I do not agree with this." Trenberth writes back, "How come you do not agree with a statement that says we are no where close to knowing where energy is going or whether clouds are changing to make the planet brighter. We are not close to balancing the energy budget. The fact that we can not account for what is happening in the climate system makes any consideration of geoengineering quite hopeless as we will never be able to tell if it is successful or not! It is a travesty!" Mann then tries to explain it in terms of natural variability: "...we can easily account for the observed surface cooling in terms of the natural variability seen in the CMIP3 ensemble (i.e. the observed cold dip falls well within it). So in that sense, we can "explain" it." But Mann is not that certain this is a full explanation, so he continues: "But this raises the interesting question, is there something going on here w/ the energy & radiation budget which is inconsistent with the modes of internal variability that leads to similar temporary cooling periods within the models. I'm not sure that this has been addressed--has it?" Trenberth responds with his concerns again: "Saying it is natural variability is not an explanation. What are the physical processes? Where did the heat go? We know there is a build up of ocean heat prior to El Nino, and a discharge (and sfc T warming) during late stages of El Nino, but is the observing system sufficient to track it? Quite aside from the changes in the ocean, we know there are major changes in the storm tracks and teleconnections with ENSO, and there is a LOT more rain on land during La Nina (more drought in El Nino), so how does the albedo change overall (changes in cloud)? At the very least the extra rain on land means a lot more heat goes into evaporation rather than raising temperatures, and so that keeps land temps down: and should generate cloud. But the resulting evaporative cooling means the heat goes into atmosphere and should be radiated to space: so we should be able to track it with CERES data. The CERES data are unfortunately wonting and so too are the cloud data. The ocean data are also lacking although some of that may be related to the ocean current changes and burying heat at depth where it is not picked up. If it is sequestered at depth then it comes back to haunt us later and so we should know about it." John, this is a very serious disagreement over the physics of planetary warming, or lack thereof over the last few years. It has the potential to profoundly impact policy-makers decisions. Can you explain the physics to Trenberth's satisfaction? Or to the satisfaction of the average layman - like myself - who is concerned about the social engineering being proposed based on this very physics?
  38. What do the hacked CRU emails tell us?
    Neil Perth, "As Corcoran points out, "the IPCC has depended on 1) computer models, 2) data collection, 3) long-range temperature forecasting and 4) communication. None of these efforts are sitting on firm ground."" This is off topic, as have several of your posts. Are you a Canuck? I am, that is why I know exactly who Terrence (Terry) Corcoran is. He is a neocon editor at the infamous "and almost bankrupt" Financial Post (Canadian paper, I use the term "paper" loosely). Rumour has it is that he is on the take from big oil.... Anyhow, he alleged pillars of AGW are nonsense. That said, yes, scientists need to do a better job of clearly communicating their findings. I would strongly advise you not to solicit your 'scientific' knowledge from the likes of Terrence, but it seems that you think quite highly of him and his and others' pseudo science. PS: You do know the editors at the National Post (a sister paper of Financial Post) have even acknowledged recently that AGW is real (an editorial on 7 November 2009). PPS: THe NP and FP have NO ethical guidelines and are not a member of any group or organization in Canada which can hold them accountable for misconduct.
  39. What do the hacked CRU emails tell us?
    "New Concepts in Global Tectonics" isn't a scientific journal neilperth. It's a newsletter, and it certainly contains some weird stuff. As I pointed out above, Ollier hasn't published anything in the scientific literature since 2007. It's pretty straightforward to establish that. What people say in newsletters isn't always very interesting or enlightening for dispassionate understanding.
  40. What do the hacked CRU emails tell us?
    Chris ........re your post stating that " Cliff Ollier hasn't published anything in the scientific literature since 2007," please find below the reference to the Cliff Ollier paper. Ollier C (2009 ), Sea level in the Southwest pacific is stable. New concepts in global tectonics. No 51, June 2009. I thought you were keeping up with such important research.
  41. What do the hacked CRU emails tell us?
    dhogaza, "Objectively" chosen or not, temperature reconstructions being what they are, it is virtually unavoidable to separate measurements into the ones that reflect a real temperature signal and those that do not. You have to make some assumptions one way or the other. If you already know what the "correct" answer is, it is human nature(at least IMO) to be more likely to reproduce that answer again. If you didn't have to choose which records reflected the true signal and which didn't, confirmation bias wouldn't matter. Cheers, :)
  42. What do the hacked CRU emails tell us?
    I see that some posters on this thread are calling for it to be closed. The point is that the hacked Hadrut emails give an insight into what is going on at Hadcrut, This is where much of the scientific data comes form on which you people base your scientific analyses of the climate. The excerpts I have posted raise legitimate questions about the lack of impartiality shown by some climate research scientists. They also show that interpretation of the climate data often produces ambiguous results and that the science is far from settled. There is also correspondence between some climate research scientists and organisations such as WWF and Greenpeace with regard to when certain announcements on the findings of the scientists should be made to the press in order to have maximum effect on upcoming intergovernmental meetings and onferences. You are free to read the full email transcripts on the Net. Closing this thread will not look good and will be interpreted as a denial that the legitimate questions I have raised above exist.
  43. What do the hacked CRU emails tell us?
    re #43/44 neilperth you're just cutting and pasting stuff..it's very boring and tedious. Cliff Ollier hasn't published anything in the scientific literature since 2007, unless he's decided to publish under a different name. Please cite or link to the "June 2009" paper that you are referring to. No one is going to be taken in by the Morner nonsense here. Surely you can find a more appropriate site to peddle this dreary stuff designed for the gullible. Dr. Morner is not the most reliable of sources [*] and hearsay and unverified allegations are boring. If you can't find any science that pertains to a subject, why bother posting. If you want to learn about contemporary sea level measurements, you can look at the science here: http://www.skepticalscience.com/Are-sea-levels-rising.html and: http://www.skepticalscience.com/A-broader-view-of-sea-level-rise.html The long cut 'n paste nonsense from your post #44 is from an email sent by someone to a climate scientist. It contains a typical trail of previous emails, one of which contains the trash that you've cut 'n pasted for our edification. It would help if you were to think about what you post, before dumping junk. [*] www.edf.org/documents/3868_morner_exposed.pdf
  44. What do the hacked CRU emails tell us?
    Do we *really* have to put up with the cut-and-paste flooding?
  45. What do the hacked CRU emails tell us?
    You mention above that “ seas level rise is accelerating”. But a recent ( June 2009 ) scientific paper by Cliff Ollier of the School of Earth and Environment, The University of Western Australia, states as follows : Abstract: Graphs of sea level for twelve locations in the southwest Pacific show stable sea level for about ten years over the region. The data are compared with results from elsewhere, all of which suggest that any rise of global sea level is negligible. The Darwin theory of coral formation, and subsidence ideas for guyots would suggest that we should see more land subsidence, and apparent sea level rise, than is actually occurring. Sea level studies have not been carried out for very long, but they can indicate major tectonic components such as isostatic rebound in Scandinavia. Attempts to manipulate the data by modelling to show alarming rates of sea level rise (associated with alleged global warming) are not supported by primary regional or global data. Even those places frequently said to be in grave danger of drowning, such as the Maldives. Also, in an interview with Dr. Nils-Axel Mörner (head of the Paleogeophysics and Geodynamics department at Stockholm University in Sweden, past president (1999-2003) of the INQUA Commission on Sea Level Changes and Coastal Evolution, and leader of the Maldives Sea Level Project – he has been studying the sea level and its effects on coastal areas for some 35 years) by EIR (Argentine Foundation for a Scientific Ecology) [http://www.mitosyfraudes.org/Calen7/MornerEng.html] he talked about the IPCC misrepresentation of sea level data: “Then, in 2003, the same data set, which in their [IPCC's] publications,... was a straight line—suddenly it changed, and showed a very strong line of uplift, 2.3 mm per year, the same as from the tide gauge... It was the original one which they had suddenly twisted up, because they entered a “correction factor,” ... I accused them of this at the Academy of Sciences in Moscow —I said you have introduced factors from outside; it's not a measurement. It looks like it is measured from the satellite, but you don't say what really happened. And they answered, that we had to do it, because otherwise we would not have gotten any trend! That is terrible! As a matter of fact, it is a falsification of the data set. ... So all this talk that sea level is rising, this stems from the computer modeling, not from observations. The observations don't find it! I have been the expert reviewer for the IPCC, both in 2000 and last year. The first time I read it, I was exceptionally surprised.
  46. What do the hacked CRU emails tell us?
    As to the fact that other paleoclimate reconstructions agree, IMO this depends on which ones you use, of course(which is where confirmation bias comes in).
    They're selected objectively, but of course you'll never be convinced of this. But I love the way confirmation bias is *assumed*.
  47. What do the hacked CRU emails tell us?
    I second with chris here. I thought maybe the political/public impacts of this might be somewhat interesting, but I realize that is not an area of focus for this site, and I'm _very_ happy with that. Keep up the good work, John! For the subject matter of the leak, I think RC is the best place right now. That said, I think there may be quite a few points raised by the material that we might, perhaps even should, discuss here, if we want to be really skeptical. It's just quite pointless to go into it in a more general discussion like this one. Rather, it may be brought up where it properly belongs, like in treatments of proxies, different temperature reconstructions, energy budget balancing, forcing/feedback estimations etc. "Light" vs "heat". Yes, exactly.
  48. High CO2 in the past, Part 2
    DrMike, a lot of the uncertainty you've expressed about the relationships between paleoCO2 levels and paleotemperature/paleo evidence for glaciations, would be resolved if you were to read the paper from which Figure 2 above was taken (click on the link "Royer 2005" in the legend to Figure 2 above). I think you'll find that Figure 2 in the top article of this thread was prepared to illustrate the broad effect of the slow relentless increase in the solar comstant over geological time, and that the temporal detail you need to answer the questions you raise are described in detail throughout the rest of the article.
  49. High CO2 in the past, Part 2
    Sure I'm willing to adjust everything in the estimations - provided we get good reasons for it. That was, for example, why I asked about Roy Spencer's basic CO2 forcing figure here. But as it is not documented, and there are theoretical as well as empirical reasons to use the ordinary figure, I use that one for now. You should also note that if Roy Spencer (qualifies as a skeptic, dosn't he?) is right, the problem of explanation of the distant past is quite small - then we are down to a temperature rise of about 2.7 oC at 5600 ppm CO2. I have not looked into the details, but I _suspect_ this may be an indication that his multiplier is too small. OR that climate sensitivity is/was very high - something I think is a very strong assumption. I think we should be careful to talk about splainin' as long as we would need 450000 qualified estimates for solar activity and CO2 just to get a time series with 1000 years resolution. The error margins (temporally) for the present estimates are huge, and typically they found the ordovician CO2 depression to account for glaciation when they had a zero hypothesis to test: That of high CO2 in spite of glaciation. There may also be huge variations in the past that we will never be able to find in any records. I see problems, both pricipally and practically, with assuming that the temperatures reflect the forcing conditions, but using it as a first, crude approximation is probably the best we have got. And it has been very useful so far, I think. By this principle, we should have had a significant cooling during the last 10 years if the CO2/GHG effects are so small as, e.g Lord Monckton asserts. For the solar activity is at a minimum, ocean circulations have been negative for temperature, and new economic activity has led to a lot of aerosols. Methane increase has halted, too. You may assume that the earth automagically adapts its albedo to such changes.. something like Lindzen's iris hypothesis - but please check the theoretical and empirical support for it before you use it for anything. You may explain what has happened in many ways, all of which may be compatible with physics and the observations, but you can't disregard that the increase in CO2 is a very plausible explanation for the lack of cooling. The feedbacks just seem to be a bit smaller than the global models would like to have it. Which could, for example, be because feedbacks decrease a bit with increasing CO2 forcing, but we don't really know. With the combination of high CH4, very high CO2 and relatively strong sun, we have entered what seems to be new territory for the planet. But still, we are talking about forcings just around 1% of incoming solar radiation, so you may safely say that effects of changes in CO2 are small in the big picture. It's just that when everything else is held constant, these changes may play out. And when everything else is not held constant, you may not be quite sure what is playing out. That's the problem with refutations based on the paleoclimatic record.
  50. Record high temperatures versus record lows
    SteveL, thanks for the Hegerl paper. Yes, point values are not really/easily comparable grid tile data from models, especially AOGCMs b/c they have pretty large grid spacing (although the grid spacing is being reduced as computing power increases). This will translate into higher resolution, which will allow for better representation of ocean currents and moist convection etc.. What you say about precip may be true-- precip. is the integrator and net result of many physical processes. Unfortunately, measuring precip. accurately over long time periods even using an official gauge network is problematic. Fortunately, many national now have radar networks, and satellite microwave technology is improving, then there is TRMM of course (only to mid latitudes though). Anyhow, I am not aware of any papers out there which investigate **large-scale** trends in precip. (using the same data platform) the last 30 years. There are, of course, papers which discuss site-specific changes. There are also lightning detection networks (proxy for convective precip.), but reliable data for N. America only goes back to 1999. I'm presently using those lightning data to explore land-atmosphere feedbacks. Very interesting.

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