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Comments 126351 to 126400:

  1. 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.
  2. The albedo effect
    You have another problem, Henry: you think about calculations without ever performing any. Now that you've moved the goalposts, show why you think AHF is wrongly calculated for Holland. Next calculation problem: you've already been shown that AHF is insignificant relative to changes in radiative forcing; do your own calculations and see how reduced transpiration owing to deforestation and desertification (not to mention changes in albedo) dwarf direct anthropogenic increases in water vapour. Or instead, actually read the stuff you've been pointed to. At http://www.realclimate.org/index.php/archives/2009/10/an-open-letter-to-steve-levitt/#more-1488 you should have read this: "For example, that 6 trillion Watts of waste heat from coal burning would amount to only 0.012 Watts per square meter of the Earth’s surface. Without even thinking very hard, you can realize that this is a tiny number compared to the heat-trapping effect of CO2. As a general point of reference, the extra heat trapped by CO2 at the point where you’ve burned enough coal to double the atmospheric CO2 concentration is about 4 Watts per square meter of the Earth’s surface — over 300 times the effect of the waste heat." Note: you shouldn't count the waste heat twice (once when it generates steam to turn the turbines and then again when the steam condenses, there IS a reason they're called "cooling towers" after all), but it doesn't make much of a difference if you do. Of course, by changing your argument to this, you should acknowledge the wrongness of your argument that AHF is mostly pumped into the oceans (which was a ridiculous claim given the small role of nuclear in power production and given the great distances between that power production and the Arctic). My last reply to you got scrubbed from the record. Let me just say (1) you don't have a coherent explanation for, well, anything and (2) you haven't demonstrated a grasp of the strongly substantiated explanation of AGW that you are trying to criticize. Do try and learn something, please, so that (in a couple of years when I've forgotten that I shouldn't reply to you) we won't cover the same ground.
  3. The albedo effect
    Henry #72: When the vapor condenses it releases the same energy that it absorbed in the process of becoming vapor in the first place. That energy that turned it into vapor in the first place is indeed counted in the anthropogenic heat flux (AHF) calculations I pointed you to. If you don't believe me you can simply look at the papers and even raw data that I pointed you to in #70.
  4. The albedo effect
    @ Steve 71, I think AHF might be wrongly calculated, even in Hld. But can you answer me on 68? See also below. @ Tom on 70: yes I would assume that the water soon condenses back to water - but do you know what happens when water condenses? well the converse of that process - namely water turning into vapor is being used by everyone in industry who has a process or a place that needs to be cooled. You can see these cooling towers in almost every factory. I know a lot about that. It is exactly that heat when the water vapor from human activities condenses that nobody seems to be counting.
  5. The albedo effect
    Henry Pool @63: Are you saying you think the Anthropogenic heat flux is improperly estimated, and therefore calculations of its negligible impact give the wrong conclusion? As Ricardo points out, it would serve you well to do some calculations. Holland AHF = 4.2 W/sq m, Holland population = 6.1 million, Holland area = 5,500 sq km ... turn that into AHF per capita = 3,800 W. Now assume 7 billion people on Earth all have the same AHF and then divide by the surface area of the planet (510 million sq km) = 0.05 W/sq m. I imagine that Hollanders have AHF about twice the average human on Earth. As pointed out elsewhere, this is a very small amount relative to changes in radiative forcing owing to CO2. If you want to blame water vapour instead of CO2 you're wrong**, but you're less wrong because you're now saying that greenhouse gases are more important than AHF in contributing warming. And, just so you know, this contradicts your position that increasing greenhouse gases such as water vapour should cool the Earth. (**Read the stuff Tom links for you in 70 and elsewhere.)
  6. What do the hacked CRU emails tell us?
    I wasn't going to bother addressing this thread at all, then felt compelled to respond to some obvious howlers. There's an interesting bit of sociopolitics involved, with some nasty precedents. In fact I think climate scientists are maybe allowing themselves to become rather over-involved with the rubbish from the pseudoskeptics. Why not just ignore all this crap, don't have anything to do with it, and just get on with doing and publishing the science? Unfortunately, it just isn't that simple. There's a similarity with the McCarthyist calamity of an earlier age (apols for a slight descent towards breaking Godwin's Law, but some specific similarities are quite strong) where the very act of accusation to contrive a psychology of distrust, forces a response in the accused which may well come across as sounding a little defensive (although in fact the responses have been admirably robust!). Inevitably, by responding to contrived accusation, a "controversy" is constructed where the focus is shifted away from the science into a sort of miasma of real and imagined deceit in which the pseudoskeptic "accusers" are comfortable. And those that may not care to engage with the science but surely know how to enjoy a witch-hunt, are all too happy to chip in with their own "interpretations"... So yes, this site should be encouraged to continue to focus on the "light" and leave the "heat" elsewhere, 'specially since John Cook does such a fantastic job of fairly dispassionate description and documentation of the science.
  7. What do the hacked CRU emails tell us?
    John, I must say that I was disappointed to see you weigh in on this CRU fiasco. The first 24 comments here were pretty constructive, but now it seems that some people feel it is OK to adopt a 'carpet bombing' approach to posting. Isn't that trolling? Others, RC et cetera are doing a good job of stemming the tide of nonsense that can be expected to arise out of this fiasco. Not that those in denial will pay any attention to context or reason, they made up their minds years ago and now this fiasco is just feeding their bias and preconceived ideas. They will read and see what they want to, regardless of the truth. This CRU hack story is about egos and politics and money for those in denial. It is best left up to the police, lawyers and judges to sort it out now. I sure do hope ClimateAudit and AirVent and WUWT have good lawyers..... Anyhow, the planet continues to warm, and there is still much science to discuss and advance; and you do an excellent job of that. Can we please stick to that much more interesting and important task? Thanks.
    Response: My initial reaction when the news first broke was to ignore it. But as it unfolded, I realised it would be a mistake to let skeptic blogs write the narrative on this issue. The whole approach of Skeptical Science is to point out that global warming skepticism misleads by focusing on narrow pieces of the puzzle while neglecting the broader picture - the job of Skeptical Science is to communicate the broader picture. The case of the CRU hack is a textbook example of this tactic - focusing on a few suggestive emails to discredit the entire field of climate science while neglecting the wealth of empirical evidence for man-made global warming. This point needed to be made but I'll be happy to move on to worthier topics as soon as I can (believe me, I'm working on it).
  8. What do the hacked CRU emails tell us?
    dhogaza, I personally don't find tree ring reconstructions all that interesting so I won't debate them at length. I think it is pretty clear though that we don't know why tree rings stopped being good temperature proxies(Briffa 1998 says this). If the tree ring proxies currently suggest that the temperature should be 0.5C cooler than they actually are, how do we know that the last time they read as 0.5C cooler than now, they aren't equally warm as today(or warmer)? 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). CO2 science has at least a couple of dozen papers that would argue that the MWP was warmer than currently. Personally, I don't have an opinion one way or another, but temperature reconstruction is very tricky IMO. Cheers, :)
  9. High CO2 in the past, Part 2
    Thanks for the discussion. Sorry for the term climate change advocates. I'm just trying to make sense of the issues at hand. I really only have one question. Will higher anthropogenic CO2 substantially contribute to warming, or are we all just spectators to forces bigger than us? I think we have a disconnect in our discussion because I think you have already made that determination. Or maybe I'm confused about the nature and details of the skeptic's argument here. How exactly do you interpret the argument of the skeptics as it pertains to higher CO2 in the past? I thought they were arguing that the data is the data. We had lots of CO2 in the atmosphere in the past, and no runaway greenhouse effect. In fact, we even had glaciations. The counter argument (which is explaining away the high CO2 levels) is that we can't compare the past to the present because the solar conditions were different. The idea of forcing is applied and forcing approximations are calculated to support the counter argument. Furthermore, glaciations as very rough proxies for global temperature extremes are superimposed over the calculated forcing to give these approximations some empirical support. Presumably, if the forcing approximations are accurate (even to a first order), the global temperature conditions will reflect the "state of forcing" at any given time. What I am saying is that I don't think the glaciations provide empirical support to the forcing calculations. The time periods in which the glaciations take place don't correlate well enough to draw any reliable conclusions. Now, if you and everone else have already decided that we don't even need to look at empirical support for the forcing numbers, then this discussion is pointless. I have not misinterpreted the physics of forcing, I'm just questioning the application of those physics since there seems to be an absence of convincing empirical support for the calculated approximations. The application of the calculated forcing factors as the primary driver of global temperatures would be much more convincing if we had a permafrost through the minimum calculated forcing periods, and no glaciations before or after. It didn't work out that way, so there seems to be a lot of splainin' to do. That's all. Thanks again, I'm not trying to be disrespectful. Just skeptical (which I think just makes me "uninformed" on this website.")
  10. The albedo effect
    Henry, water vapor added by humans merely falls out of the atmosphere within an average of 10 days. See my explanations on the water vapor thread both here and here.
  11. Water vapor is the most powerful greenhouse gas
    h-j-m wrote "for quite a long time now it is known that nature no way can be understood in a linear fashion as your argumentation suggests." The role of water vapor in global warming is not at all "linear." It is rather complicated, and so is scientific knowledge of it. Introductory explanations of it are less complicated to suit readers who "did not want to delve into the complexities we are dealing with here if only for the reason I don't know enough to argue in any specialized field," as you wrote. If you suspect an explanation is unrealistically simple, you should pursue a more complete explanation. That is easy by clicking on the links to scientific papers provided in John Cook's original post, and indeed by clicking on the link I provided in my earlier response to you. One particularly relevant and short article is by Dessler and Sherwood (2009, Science, available for free), which specifically mentions local versus global effects, and which I think you in particular would find very informative and comprehensible.
  12. What do the hacked CRU emails tell us?
    Eh. This is being discussed at great length everywhere else. Why bother to jump in? As far as I can tell, it's all about personalities, not so much about science. Your site's niche market is presenting well-written, clear, informative, and interesting explanations of science topics, often with mentions of papers that don't receive a lot of publicity elsewhere. My opinion doesn't really matter, but I'd encourage you to generally ignore whatever the manufactured controversy of the week may be, and just keep writing about the science. Cheers, Ned
  13. Water vapor is the most powerful greenhouse gas
    Dear Tom Dayton, deliberately I war referring to applied logic in my argument because I did not want to delve into the complexities we are dealing with here if only for the reason I don't know enough to argue in any specialized field. But I fear your reply forces me to elaborate on my point. As to my knowledge anything happening in the atmosphere is occurring locally depending on a lot of causes that are satisfied just at the spot. Any method of generalizing and narrowing down to only a few or even one cause (atmosphere temperature in this case) is not appropriate in my view due to the fact that we are dealing with nature here and for quite a long time now it is known that nature no way can be understood in a linear fashion as your argumentation suggests. I might mention that only a few decades ago it was the complexity of the earth's atmospheric system that triggered a whole new branch in mathematical science known as chaos theory. The atmosphere being a chaotic system clearly rules out any notion of insignificance due to amount unless any significance is disproved. Anyway to state my point in a somewhat broader consent: The matter of water and how we handle that should be given a much higher priority not only but also with respect to global warming. The reason should be obvious: The fact that it got harder in the last decades to get access to fresh water due to dwindling surface reservoirs and by now we already started using fossil reservoirs of it poses an immediate threat to mankind's existence as devastating as global warming if not even worse.
  14. The albedo effect
    I will look at your interpretations of the definitions later, but I think we are straying now from the the two experiments that I have suggested. 1) Are we agreed that in experiment 1 there will definitely be a measuruable difference between the surface areas of A and B, meaning that AHF must/may have some significant bearing on global warming. 2) Are we agreed that in experiment 2, if we do not use air but add 350 ppm CO2 to the 80/20 mixture, there will be no measureable heat retention, i.e. no difference in the surface areas between A and C and between B and D. My conclusion would be that the concentration of CO2 is too small to make any difference. In this experiment, it will not be possible to prove that the increase by 25% of CO2 since 1960 has any significant bearing on global warming. As it is in this experiment so it is probably also in practice. And that, in my opinion, means that the influence of CO2 on global warming is probably grossly overstated. Now if instead of CO2 we were to add 1 or 2 % water vapor in experiment 2, I am sure that there may well be some measurable influence on heat retention. And that brings me to some human activities that were probably never included in any measurements of AHF: namely those activities that produce water vapor a) nuclear plants b) burning of fossil fuels c) building of shallow water reservoirs and dams for consumption and irrigation - also swimming pools; the sun heats the water up and subsequently causes more water vapor. I am sure I have not covered all human activities causing more water vapor, for example, when we cook, or have a bath or shower. Washing dishes. The list is endless. We boil. We make water vapor. All the time. MY point is that the increase in water vapor caused by human activities is probably much larger than the increase in CO2 and the effect on heat retention much more pronounced. I think even Tyndal would have agreed with me on that?
  15. What do the hacked CRU emails tell us?
    I just want to give an example of how this is playing out around the world. Aftenposten, the most influential Norwegian newspaper, has been running a lot of good articles on climate change. But when this turns up, it is handled as classical conflict stuff, and the basic journalistic principle is to give both sides equal opportunities and weight. In today's article, the "skeptic" side is represented by a well-known "skeptic", professor Olav Martin Kvalheim, University of Bergen. http://www.aftenposten.no/nyheter/uriks/article3385865.ece Kvalheim refers to "Mike's Nature trick", and I have no doubt he is able to understand this, but he still presents this as proof of data manipulation: "This, in Kvalheim's opinion, shows how temperature measurements are manipulted to fit with the model of temperature rise in cliate crisis". He then continues to talk about big research money, to end up with: " - Aren't there even stronger economical interests on the skeptics' side? - You mean that the oil and car industry support the skeptics? No. From the skeptics' side this is pure idealism - many view the climate panel as a propaganda machine, and want to defend scientific principles. " I really hadn't believed he would spin it in such a cheap and dirty way. But the impact is much more short-lived this way, and he surely isn't increasing his credibility in the informed public debate in Norway.
  16. An overview of Antarctic ice trends
    Why delete the discussion on GPS data?
    Response: I haven't deleted the GPS discussion, it can be found at the "official" Antarctic ice page as opposed to this page which is just a blog post. I know it can be a bit confusing, especially when content is duplicated (the website was originally never intended to have a blog - I caved to peer pressure on that point). For the record, the exchange between SNRatio and Chris about Bevis 2009 is the kind of discussion I like to see on this website - poring over the peer reviewed research to gain a clearer picture on what's happening with Antarctic ice.
  17. Water vapor is the most powerful greenhouse gas
    h-j-m, I'm sorry, my previous reply regarding extra water falling out of the atmosphere did not answer your question. Please let me try again: There are vast pools of liquid water available to go into the atmosphere, and vast seeds for condensation to help water vapor drop out of the atmosphere. Indeed, both those activities happen constantly. So neither of those is a limitation on the amount of water vapor in the atmosphere at any one time. Humans' provision of more water is only a drop in the bucket. What does primarily limit the amount of water vapor in the (Earth's) atmosphere is the atmosphere's temperature. At a given temperature, adding more water vapor "nearly instantly" forces water vapor to drop out of the atmosphere. "Nearly instantly" in this context means "so fast that there is no time for significant atmospheric heating from the extra water vapor." The opposite happens as well: Water vapor removed from the atmosphere merely leaves room for the other water vapor that is constantly being added. The net effect all those processes is no change in temperature nor in the amount of water vapor. Water vapor is not a "forcing" of temperature. All the above is not just theory; it is observed fact. It was true before humans had even evolved. If it were not true--if water vapor was not limited by temperature--then there would no longer be liquid water on the Earth's surface. It would all have evaporated and none would have condensed. Water vapor could be a forcing if there weren't any liquid water lying around. On some other planet that doesn't have enough water to fill its atmosphere's capacity for water vapor, adding water vapor to the atmosphere certainly would cause that vapor to stay in the atmosphere. But here on Earth, we've got an abundance of water. What's needed to increase water vapor for more than 10 days is an increase in atmospheric temperature. That initial increase can't come from added water vapor (as I just explained), but it can come from anything else--anything that is a temperature forcing. For example, it can come from an increase in the Sun's output, or an increase in greenhouse gases. Once the temperature has increased, less water vapor drops out of the atmosphere. That does indeed then increase the temperature, which is why water vapor is a "feedback" from other causes of temperature increase. But the amount of temperature increase is strictly limited by the converging series I described in my previous comment.
  18. Water vapor is the most powerful greenhouse gas
    h-j-m, evidence supporting my contention of the triviality of energy humans add directly to the atmosphere is in my two comments on another thread here and here.
  19. Water vapor is the most powerful greenhouse gas
    h-j-m, the amount of energy added directly to the atmosphere by humans is a forcing of less than 1% of the forcing from greenhouse gases added by humans.
  20. Antarctica is gaining ice
    I think the point in #11 is that most attempts to estimate ice mass balance in the antarctic reply on IJ05 or ICE-5G to estimate PGR/GIA. Just to point out that similar work has been done for Eastern anarctic, here, with similar conclusions. Suggesting further error in the previous ice mass estimates including Velicogna 2009. This publication suggests the green line in Fig1 should maybe showing a gain over time. I'd highlight the second half of the Bevis quote in #12 which states that the 33Gt yr-1 is only a provisional figure (and covers only part of Western Antarctic) I'd be keen to see some full estimated that take into account the GPS data.
  21. Water vapor is the most powerful greenhouse gas
    h-j-m, there is no actual contradiction between "extra" water falling out of the atmosphere, and the increased temperature due to the presence of extra water vapor allowing more water vapor to stay in the atmosphere. Additional water vapor increases the atmosphere's temperature by enough to allow an increase of the atmosphere's water-vapor-holding-capacity by only a fraction--a proportion less than 1. That resulting increase in water vapor then repeats the cycle, but now only that same fraction of the previous fraction. It is a converging series. The increases are the same percentage each round, but since the percentage of increase is less than 100%, the increase gets progressively smaller until it reaches zero.
  22. Why is Greenland's ice loss accelerating?
    Your figure 2 seems to indicate that ice-mass loss in Greenland seemed to accelerate around 2000. This is also around the time global atmospheric temperatures seemed to flat-line. Isn't it classic thermodynamics, that the temperature of a system won't increase while a material is changing phase? Is it possible that the 'acceleration' of ice-mass loss from Greenland, and perhaps other ice-areas of earth as well, is responsible for the perceived deceleration in global temperature increase seen in the last 10 years?
    Response:

    The amount of energy that goes into ice melt is fairly small compared to the amount of energy being absorbed by the oceans. In the figure below, all the energy gone into ice melt is included in the red "Land + Atmosphere" segment:



    Note that the oceans are still absorbing massive amounts of energy even during recent years when surface temperatures have either flattened or shown short term cooling.

  23. What do the hacked CRU emails tell us?
    Readers of this blog may be interested in a very recent paper which seems to be able to solve the tree ring mystery: "Recent unprecedented tree-ring growth in bristlecone pine at the highest elevations and possible causes". Matthew W. Salzer, Malcolm K. Hughes, Andrew G. Bunn, and Kurt F. Kipfmueller http://www.pnas.org/content/early/2009/11/13/0903029106.full.pdf+html
  24. What do the hacked CRU emails tell us?
    "places recent global warming trends in the context of temperature changes over longer time scales" John, excellent explanation - after following all the RC thread I still hadn't understood what was being said until I read your few lines. And dhogaza - "The decline isn't real. The instrumental temperature record shows that it isn't real. Global temps over the last fifty years have not declined, they've increased, despite the tree-ring data" - full marks too for a clear explanation. Astonishing to think that this nonsense is the thing that is getting Deniaworld excited. I have a discussion here http://www.blognow.com.au/mrpickwick/182891/Dream_of_money-bags_tonight.html about the context what is going on.
    Response: Normally, WWII analogies in climate discussions are a bad idea. But the dropping of foil plates to mask the Allied invasion is an apt metaphor.
  25. Record high temperatures versus record lows
    I'm talking to myself on this thread a lot; here I'm responding to my own question regarding a potential disconnect between model expectations of more extreme weather and the surface station record described above that shows, overall, less extreme temperatures. I've skimmed the draft Hergerl et al paper because it was a draft and because it is not new: http://www.env.duke.edu/people/faculty/hegerl/hegerlextremesresub.pdf There is probably better info out there now. I found the following enlightening, though: "daily station data are not readily comparable with daily model output." The model works on larger spatial scales and, despite what this sentence implies, longer temporal scales are also better for comparison (according to text shortly following the quotation). How poorly comparisons work will depend on how the shape of the distribution changes (can be read as how the extremes relate to the mean as the climate changes). The abstract summarizes how the mean and extremes are expected to change: "The estimated signal-to-noise ratio for changes in extreme temperature is nearly as large as for changes in mean temperature. Both models simulate extreme precipitation changes that are stronger than the corresponding changes in mean precipitation." I've glossed over a lot of detail here, and probably the issue deserves better investigation than I've given it. But I think a safe summary is that (1) station data don't make great comparisons to model outputs and (2) increases in extreme weather may be manifest more strongly in precipitation than in temperatures.
  26. How do we know CO2 is causing warming?
    Good that it has not been deleted. The endless repeating of the same faulty arguments is enlightening of the deep will to not to look at the science. "coincidence is claimed to be proof of causation" true that coincidence (correlation?) is not a proof, but it's not used for sure on the AGW part. I've seen many more correlations used against AGW, even that the sun (or GRC, or clouds, or magnetic field or even length of the day!) correlates better than CO2 with the temperature record. "admission that AGW is a matter of consensus (political, not science)" Yes? I've heard this somewhere ... on skeptic blogs ... they admit that someone else admit that ... oh Lord ... "we should eliminate any speech of those who don't automatically agree with everything we say" well, and how comes that there is so much discussion around? How comes that scientific papers against AGW continue to appear (though from the same few guys)? Because of their super power that can not be defeated? "the primary "proof" of AGW theories is still based on computer programs" I bet this is just lack of knowledge of the discovery of global warming. No need for computers, simple calculations can be done by hand. On the contrary, including in the picture as many details as possible and having future projections as accurate as possible require intensive calculations.
  27. What do the hacked CRU emails tell us?
    re #13 HumanityRules, I'm not going to link to the email you're referring to, since it's a personal email that refers to the inability of a distinguished scientist to sttend a meeting due to illness. It's pretty obvious that the phrase is part of a general personal reminiscence between scientists. The CRU is a leading institution in climate research. It's one of the three centres that compile surface temperature data for constructing past and contemporary temperature anomalies from direct surface temperature measurements. You can learn about it here: http://www.cru.uea.ac.uk/
  28. What do the hacked CRU emails tell us?
    re #24: Your points don't make a lot of sense TruthSeeker. 1)-3) a). There isn't really anything hidden. Briffa et al. themselves highlighted the divergence issue already in 1998 in Nature, and pointed out the late 20th century lack of response of high latitude trees to rapid warming meant that this part of a reconstruction was demonstrably incorrect [*]. However the tree response to temperature was reliable over the previous decades of the 20th century and back to the 1880’s. So that defines a range of temperature responses (range/rates) in which the proxy is expected to provide reliable temperature reconstructions in the past. b) Since we now have paleotemperature reconstructions from a large range of proxies and that don’t involve tree rings (e.g. [**]), and cover the same period as the ones under discussion in these very old emails, we can see that the analyses of 1998 have pretty much held up to the test of time. 5) Not sure what you mean there. Please clarify. 6) This is about one paper out of 1000’s of papers published in the climate-relate field. It was so obviously dodgy that the failure of the review process caused the editorial board of Climate Research to resign, and the publisher himself stated that the paper shouldn’t have been published as it was. If we have to pretend that we can’t recognise rubbish when we see it, then we’re in trouble (and easy prey for propagandists and other charlatans). 7) Not sure what you’re referring to there. No-one decides what is or isn’t peer-reviewed other than an editor, and it’s very unlikely that an editor wouldn’t send a paper for peer-review, unless possibly if it didn’t conform to the requirements of the journal (character length, number of figure in a communication, etc), or if it's a paper sent to Nature or Science, in which case an editorial decision is made about whether a paper makes it past a preliminary hurdle based on “general interest”, “sexiness”, or “newsworthiness”. [*] K. R. Briffa et al. (1998) Reduced sensitivity of recent tree-growth to temperature at high northern latitudes Nature 391, 678-682 [**] M. E. Mann (2008) Proxy-based reconstructions of hemispheric and global surface temperature variations over the past two millennia. Proc. Natl. Acad. Sci. USA 105:13252-13257
  29. Water vapor is the most powerful greenhouse gas
    The article states: If extra water is added to the atmosphere, it condenses and falls as rain or snow within a week or two. Similarly, if somehow moisture was sucked out of the atmosphere, evaporation would restore water vapor levels to 'normal levels' in short time. Implicitly that says that humans can not add water vapor to the atmosphere. But from the pure logical point of view this contradicts the very first statement (from the green box): Water vapor is the most dominant greenhouse gas. If it is a greenhouse gas then it will act as such i. e. warm the atmosphere in effect. As a result the atmosphere will hold more water vapor including a fraction of what was added by men. If it's not, then all the talk about feedback is just gibberish and all conclusions from it, including (I assume) all the models, can surely be entrusted to the trash can. Please don't even consider the argument about the tiny amount by comparison. That has clearly been ruled out in the global warming debate. What I'd like to see are some serious estimations about the anthropogenic part when it comes to water vapor. Including besides the obvious ones e. g. the amount of water contained in a swamp vs. a palm oil farm per square kilometer or tropical rain forest vs. Cattle pasture or corn field. So if you start thinking about it there is hardly an end to find even restricted to the respect of land use that might result in releasing water to the atmosphere. Which then leads me to my last point. That is about direct heating the atmosphere by our energy production (of cause from burning fossil fuels and using nuclear - because all other sources are more or less conversions from sunlight). I think this belongs here because in most cases water vapor acts as a transport medium in the process. It gets vaporized by the produced energy and releases it due to condensation in the atmosphere. Due to the overall efficiency of our industry we speak about 50+ % of all energy generated. So far I have been unfortunate in finding anything about that matter so I thought it might be a good idea posting this question here.
  30. What do the hacked CRU emails tell us?
    The decline is the divergence problem, you can't say one is real and not the other. IAC, the point is, if we know that recent tree ring data for which we have independent temperature data shows that tree rings are not (currently) a good temperature proxy, why should we assume they were a good proxy for times when we do not have much independent temperature data? Confirmation bias, anyone?
    No. 1. Not all tree ring data sets show the divergence problem, yet they show the same general pattern of climate in the past than those that do. 2. There are a dozen or so paleo reconstructions that DON'T USE TREE RING DATA AT ALL that show a similar pattern in past climatic conditions. 3. We know from tree physiology unrelated to paleoreconstructions that trees near their altitudinal and latitudinal range limits are frequently growth-limited by temperature. 4. They don't just count tree rings, but rather for variation in tissue that is known from studies into tree physiology to be due to temperature being a limiting factor in growth. etc etc etc. The problem with simplistic rejection of science you don't understand is that unlike you, specialists *do* understand their subject very well. Which leads to statements like:
    4)Libel?? see tree rings, they use it when it supports their claims and through it out when it contridicts. That isn't libel that is true and has as you say "something that's been widely discussed in the open professional literature for a decade."
  31. How do we know CO2 is causing warming?
    I find it sad that those who point to the attached papers as further or any "proof" of anthropogenic warming apparently failed to critically read the papers. In the various pro-AGW arguments presented I see the idea that coincidence is claimed to be proof of causation, admission that AGW is a matter of consensus (political, not science), and the usual "we should eliminate any speech of those who don't automatically agree with everything we say". It's sad, really. The simple fact is that the primary "proof" of AGW theories is still based on computer programs which were designed to prove just that and which, if you've been paying attention for the past ten years, deliberaetly flawed presentations of temperature data aside, have been proven wrong once again. Over the past decade human production of CO2 went up and temperatures did not. You can deny it all you want, you can delete this post all you want, it's still true.
    Response: I must confess, my finger was hovering over the delete button when I first read this comment. But instead, I will follow Riccardo's example in the following comment and use this as a teachable moment:
    • Firstly, you describe several claims of pro-AGW arguments. Eg - "coincidence proves causation", "it's based on computer programs", "AGW is a matter of consensus". They are not the claims made by climate scientists. These are characterisations of pro-AGW arguments made by skeptics. The evidence for man-made global warming is based on direct observations and direct causation.
    • In fact, that is the main point of this post - empirical measurements prove that more CO2 leads to an enhanced greenhouse effect. This means CO2 is "trapping" more heat. Therefore the planet is accumulating heat. And more heat means higher temperatures. That's not coincidence but direct causation.
    • Over the past decade, the enhanced greenhouse effect continues to trap heat. Observations show that the Earth's total heat content continued to rise past 1998, the year when skeptics claim global warming stopped. More than 90% of global warming goes into the oceans. Direct measurements of ocean heat content find that the ocean is still accumulating heat. The empirical data is clear. Global warming is still happening.
    It's quite easy to set up straw arguments like "coincidence is not causation" or "AGW theories are based on computer programs". But the evidence for man-made global warming is empirical, based on direct measurements of an enhanced greenhouse effect. I'm not sure if you read the article above but I would strongly recommend rereading it then reading a broader overview of the empirical evidence for man-made global warming.
  32. What do the hacked CRU emails tell us?
    dhogaza, The decline is the divergence problem, you can't say one is real and not the other. IAC, the point is, if we know that recent tree ring data for which we have independent temperature data shows that tree rings are not (currently) a good temperature proxy, why should we assume they were a good proxy for times when we do not have much independent temperature data? Confirmation bias, anyone? Cheers, :)
  33. The albedo effect
    Henry Pool, apart from the erroneous interpretation of the Wikipedia article (by the way, better study these topics from a textbook or a specialized site like Tom Dayton suggested), your idea point to a constant albedo of 0.5 for any plane with an atmosphere, which is definetely wrong. You should always contrast your undesrtandings with numbers and with other situations. The formula of the inrreased forcing is one of the many that can be used; it's of the most used and is found many aproximate calculations and in the IPCC reports. Sometimes the coefficient is slightly different from the one i gave you.
  34. The albedo effect
    Henry, the Wikipedia entry you quoted says "...re-emit much of the energy." Your interpretation of "re-emit" meaning "the molecule becomes sort of like a little mirror...and the molecules start reflecting" is completely wrong. RKM.com.au provides an excellent animation (at the top right of the page), an accompanying static diagram (at the lower left of the page) and a step-by-step textual explanation of it all (at the right side of the page). Please don't merely skim all those as you seem to usually do. Study carefully. Notice that there is no second infrared photon hitting the molecule and being reflected. Instead, the molecule "re-emits" the same energy it just absorbed. "Re-emit" means "emit the same energy it just got." The molecule stores the energy it absorbed by putting it into vibration of the bonds among the atoms in the molecule, as is explained in the text accompanying that picture. The energy in those vibrations then is emitted as infrared radiation, with the result that those vibrations cease. The energy is neither destroyed nor created. It merely changes location and form from photon to bond vibration and back to photon. Molecules have several modes of vibration; animations of those are provided by the Journal of Chemical Education site (see Figure 2 there). Each of those modes can contain energy independently of the other modes, and several amounts of energy can be contained by each of the modes. So even if a molecule has absorbed one photon's energy, it has enough storage capacity to absorb more. The re-emission happens almost instantaneously after the absorption that triggered it, which means the molecule's storage is freed up almost instantly after it is filled. But if occasionally a photon does hit the molecule while the molecule cannot absorb any more, the photon does not get reflected because of that; it does indeed just pass through/around. (Remember, a photon is actually/also a wave packet.) Reflection is a completely different phenomenon that is governed by oompletely different laws, as we have explained to you before. An excellent explanation of greenhouse gas bonds, vibrations, energy storage, and energy re-emission is in David Archer's free "Lecture 6: What Makes a Greenhouse Gas". (It's in Chapter 4--the sixth lecture in the overall list of lectures.)
  35. What do the hacked CRU emails tell us?
    A general point There are lots of vague references to what are presumably rather specific emails. If anyone makes a comment about a particular point, why not specify exactly what email(s) the point refers to. Then we can assess the context etc. This relates to post #13 (HumanityRules extraced single sentence), post #15 (Truthseekers list), post #19 (Nickle's PhD comment) etc. HumanityRules (post #13) has linked to the hacked archive. So simply put the date of the email(s) that you are referring to, rather than posting single extracted sentences or making unspecified assertions.
  36. The albedo effect
    Hi Riccardo: where did you get this formula? The concentrations measured in what units? Quote from Wikipedia (on the interpretation of the greenhouse effect); "The Earth's surface and the clouds absorb visible and invisible radiation from the sun and re-emit much of the energy as infrared back to the atmosphere. Certain substances in the atmosphere, chiefly cloud droplets and water vapor, but also carbon dioxide, methane, nitrous oxide, sulfur hexafluoride, and chlorofluorocarbons, absorb this infrared, and re-radiate it in all directions including back to Earth." The way I understand this process is as follows: Water and carbon dioxide behave similarly when exposed to infra red radiation. Each molecule accepts one or more photons. Once this transaction is completed the molecule becomes sort of like a little mirror to infra red radiation (at those wavelenth bands where absorption takes place) and the molecules start reflecting the infra red. Because of the random position of the molecules we may assume that at least 50% of that radition from earth is radiated back to earth. The process repeats itself. Obviously when the sun's radiation hits the water vapor and the carbon dioxide the same thing occurs, but now 50% is reflected out to space. I assume/ would think that if the radiation stops, the photons in the molecule are converted to kinetic energy to any of the molecules in the immediate vicinity How do you understand the definition? Consequently I also disagree with you on your last point. The ozone is very little. How much UV do you think can be absorbed? Once the molecules are saturated the UV is blocked - like a mirror - and light being what is does best, it has to move, so it moves.....out!! The thicker the layer of ozone, the more UV light is reflected, hence the increase in earth's albedo.
  37. What do the hacked CRU emails tell us?
    The "trick" to "hide the decline" dates from 1999. As 1998 was a record hot year, it is hard to imagine what real decline in temperatures the sceptics/deniers think was occurring that needed to be hidden. You're thinking the wrong way round. It's not that they were using a 'trick' to hide a divergence. They were using a trick to hide a 'decline' That was the language used. I've no reason to believe that they didn't mean what they said. ie. It's a case of manipulating things to fit the hypothesis, not trying to explain what doesn't fit the hypothesis. Combine that with all the other details in the emails and it shows a particular unpleasant group of people. Imagine plotting to get a PhD removed from a student because their results were awkward? In reality, its a disaster for climate change advocates. They have been hiding data, and its clear they have done this now. They have also talked about destroying data that is subject to a FOI request. That is a criminal offence in the UK
  38. What do the hacked CRU emails tell us?
    The "trick" to "hide the decline" dates from 1999. As 1998 was a record hot year, it is hard to imagine what real decline in temperatures the sceptics/deniers think was occurring that needed to be hidden.
  39. The albedo effect
    Henry Pool, still off topic here, but for you knowledge a reasonable aproximation for the differenze in forcing of CO2 alone in the atmosphere is deltaF=5.35*ln(C2/C1) in W/m2 with C1 and C2 two CO2 concentrations. You can play around with those numers if you like. You idea of limited absorption is absurd and this is once more missing basic physics. It would require each molecule to stay in an exited state forwever which is simply impossible in any real world. Saturation experiments has indeed been done, but they require ultrafast high power lasers As for the future closure of the ozone hole, yes, it will be a negative forcing localised in the stratosphere which is expected to cool somewhat less; not due to reflection, though, but absorption of some UV.
  40. The albedo effect
    @ Steve and Tom on 56 I note that there are some unbelievably big variations in the AHF measured. Like in my country of birth (Holland) they measured 4.2 W/m2. However, globally, it is reportedly only 0.03 W/m2. How can that be? I think there are some missing data, mostly from the underdeveloped countries?> On the subject of where to easily note global warming: Note that nuclear facilities are all placed near oceans or seas because they need tons and tons of water to cool. The AHF warming goes mostly into the oceans.... In many places, AHF takes place mostly near mountains or mountain ranges. (constant water supply for human activities)
  41. The albedo effect
    @Tom on 55 The tests you refer to all compare air with 100% CO2. That was exactly not the idea of my experiment. I am a chemist. I know that if you change concentrations (in a solution) you might get different properties (as a whole). In my experiment, I wanted to know what difference 350 ppm's CO2 makes on heat retention. Just admit it: at that concentration it is probably not even measureable in my experiment.... However, a doubling of a release of energy (to simulate the doubling of the earth's population) in our (earth)vessel was easily measurable. Or do you also doubt the outcome of my experiment 1?
  42. What do the hacked CRU emails tell us?
    Interesting. You provide anictdotal evidencen to suggest that Tree rings are no longer any good while I suggest that if they arn't currently any good who has evidece that they were ever any good.
    Response: The evidence that tree-rings are a reliable proxy can be found in Briffa 1998 that show tree-ring width and density show close agreement with temperature back to 1880. To examine earlier periods, one study split a network of tree sites into northern and southern groups (Cook 2004). While the northern group showed significant divergence after the 1960s, the southern group was consistent with recent warming trends. This has been a general trend with the divergence problem - trees from high northern latitudes show divergence while low latitude trees show little to no divergence. The important result from Cook 2004 was that before the 1960s, the groups tracked each other reasonably well back to the Medieval Warm Period. Thus, the study concluded that the current divergence problem is unique over the past thousand years and is restricted to recent decades. More on the divergence problem...
  43. The albedo effect
    on 52&54 yes we have strayed from the subject (although I still have good hopes that mostly the noted increase in ozone will bring us global cooling due to an increase in earth's albedo and a closing of the ozone hole) but I think this straying is and was necessary. We have touched on a new subject now: AHF. Maybe another post? Anyway, Tyndal proved that it was mostly water keeping our planet warm, and he was right about that. Don't forget that at about 70% RH you have about 1-1.5% water vapor in the air, compared to CO2 of 0.038% (which really is next to nothing compared to the H2O) the point that you, Riccardo, seem to forget is that you think that the "absorption" process is limitless. It is not.Every molecule can only absorb that much photons. After that the light must keep on moving, so where it it wanted to move (because the molecule is now full) it cannot. It cannot move through either (like it does through N2). so it has to scatter. At least 50% is scattered to out of space. I( did not provide prove for my experiment, because I donot have the equipment. But I can easily guess the outcome!
  44. Darren Lewin-Hill at 20:34 PM on 22 November 2009
    What do the hacked CRU emails tell us?
    TruthSeeker, refer to @dhogaza at the end of comment 10 re the evidence of the instrumental record. I guess you don't say the instruments have stopped working because the tree-rings don't agree. Comment 14 goes on to suggest that other factors may well be in play re the tree-rings. For example, I might grumpily say it's hot and that has been a good proxy for the outside temperature in the past (e.g. I tend to say it when it reaches about 25C inside), but while I'm away on a work trip my wife installs an air-conditioner and sets the thermostat at 22C - pleasant but not necessarily obvious. Having lazed away the weekend inside on returning from my trip, would I sit there looking in disbelief at a TV weather report of 37C, or go looking for another explanation (i.e. the new air-conditioner)? I don't think I'd be suggesting there was something wrong with the instruments of the meteorologists, do you? I'd also imagine that the tree-rings would have continued to be a good proxy had the conditions in which they formed remained continuous in the divergence period with the time when they more closely reflected temperature.
  45. The albedo effect
    Ok, I will go through all of your comments in more detail later. Are you people saying that in my experiment 2, there will actually be something of an increase in heat retention to obeserve? if yes, how much in the concentration range of 0.01 to 0.05 % CO2. I don't think a child can do this. I think I made a mistake by putting in air (Experiment 2), I think we must leave the water vapor out of it, just stick with the 80/20 N2/O2 and then add the 270, 350 and 500 ppm CO2 (we need to know exactly where we are going) These are the results I was hoping to find somehwere and never got it. even so, I think there will never be as much heat retention by CO2 as in experiment 1, between A and B.
  46. What do the hacked CRU emails tell us?
    I am somewhat surprised by these responses. I find significant problems with the following discoveries in the emails: 1) Tree ring data is good when it supports the hypothesis, but must be hidden when it conflicts? None of you take issue with that? 2) Through the email text it is pretty clear that their approach is to validate data based on how well it fits to the hypothesis, not how well the hypothesis fits to the data 3) Why is it ok to obstruct the freedom of information act? What do they have to hide? 4) Why do they collude to exclude peer review of articles that question their hypothesis, I find it most disturbing since they use the lack of peer review to discredit the skeptics. This truly brings into question both their ethics and scientific agenda. The models have been notoriously inaccurate in making future projections, and now we find that even the week claims of model accuracy are nothing more than the result of massaged data. There is an old saying, that if you torture the data enough, it will confess.
  47. What do the hacked CRU emails tell us?
    I'm not sure I understand why a change would occur in sensitivity, but I'm not a scientist.
    It doesn't matter that you're not a scientist, because they don't understand either. That's why the divergence problem is ... a problem! :) Seriously ... But they're working on it. You might google "Liebig's Law of the Minimum". In plain language, this essentially says that growth is typically limited by the most scarce resource/factor. For a tree up high near the specie's tree line, this is often temperature, often the number of warm days over a short period of summer. Lower down, you may find many more warmer days, the same precip, the same nutrients more or less, and growth patterns will be different because the scarcest resource might be (say) soil nitrogen. It's warm enough so the tree will grow rapidly enough to be limited by that rather than temps. Does this make sense to you? So the confounding factor as temps have warmed for some of the series might simply be that temperature is no longer the most limiting factor. Maybe precip has dropped. Maybe something else is going on. This is the kind of stuff they're working on - trying to understand what factors have changed to cause growth patterns to change. I think they'll work it out. Science typically does ...
  48. The albedo effect
    Henry, there is even a video of an actual child explaining his actual experiment of the sort I previously pointed you to.
  49. What do the hacked CRU emails tell us?
    The emails have been archived in a searchable form here. http://www.anelegantchaos.org/cru I was wondering what peoples thoughts are on this comment from one "Despite its relatively small size, CRU has had (and continues to have!) a rather remarkable "fingerprint" in the world of climate science." I had wondered about the influence of this organisation.
  50. Darren Lewin-Hill at 14:12 PM on 22 November 2009
    What do the hacked CRU emails tell us?
    @dhogaza Thanks for further explaining that. I'm not sure I understand why a change would occur in sensitivity, but I'm not a scientist. That what was claimed to be hidden was in fact explicit in the literature is, I think, sufficiently reassuring. As for the denialists, I'm sure they'll continue to make capital of this stuff, but the point about the broader, and quite obvious, climate picture should serve as a powerful contradiction to their nonsense.

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