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Comments 126551 to 126600:

  1. 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.
  2. 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.
  3. 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
  4. 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.
  5. 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?
  6. 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.
  7. 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.
  8. 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.
  9. 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.
  10. 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.
  11. 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.
  12. 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.
  13. 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.

  14. 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
  15. 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.
  16. 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.
  17. 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.
  18. 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/
  19. 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
  20. 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.
  21. 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."
  22. 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.
  23. 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, :)
  24. 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.
  25. 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.)
  26. 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.
  27. 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.
  28. 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
  29. 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.
  30. 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.
  31. 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)
  32. 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?
  33. 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...
  34. 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!
  35. 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.
  36. 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.
  37. 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.
  38. 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 ...
  39. 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.
  40. 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.
  41. 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.
  42. The albedo effect
    Henry, if you want to see the raw data used by Flanner so you can do the calculations yourself (see my previous comment on 22 November), you can get them from this web site he put up. He wrote there, "Globally, in 2005, this anthropogenic heat flux (AHF) was +0.028 W/m2, or only about 1% of the energy flux being added to Earth because of anthropogenic greenhouse gases." That page also has some other references, if you don't want to pay to see his journal article.
  43. What do the hacked CRU emails tell us?
    For the science, this has minimal impact. I have seen a couple of comments from more skeptical scientists who in fact have gotten more confidence by seeing that these guys are almost obsessed with science. It will lead to even more focus on openness, quality and the peer review process. Very good. It wouldn't harm with a bit more focus on ethics, either. In the RC posting about this they pointed to Newton, who was no angel. OK, then I would say that Newtonian ethics is much more outdated than Newtonian mechanics :-) The political impact will be much bigger, but mostly short term. The IPCC will be more dependent on the science and the reasoning, and less on the authority of leading scientists. It may be a setback for international negotiations, but not for very long. And I think we may even get better and more robust policy measures this way. The most important thing in the current situation, is that the models have been somewhat oversold, and the IPCC estimates have not been as conservative as they should be. In addition lots of time and energy has been used unproductively on tree-rings, hockey-sticks and "unprecedented warming". Look at this discussion, too: The divergence problem is real, and interesting, but how much of current climate science depends on it, really? To me, it seems mostly to fuel denialists' attacks. The present situation, where feedback estimates tend to be reduced over time, is most unfortunate. James Hansen's old curves, using 4 deg/doubling, may increasingly be used as examples of "alarmism" by "skeptics" and among the leaked emails can be found what Kevin Trenberth wrote to Tom Wigley 20091014: "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." This is of course relative to Trenberths very high standards, but still quite different from the impression of rather small uncertainties. Which is also borne out by the models not performing very well for the last decade. In fact, a few more years with little or no warming would show them to be in error - something that would not have happened with more conservative estimates. According to the models, the development of the last decade is a bit anomalous - I'm not sure it is, and something like what has happened, should have been announced in advance.
  44. The albedo effect
    Henry Pool wrote "I have clearly proven to you with my experiment no.1 that global warming is most probably caused by the increase in energy released in the atmosphere due to human activties." Henry, if you demand more detailed evidence than the quick quantification that Steve L quickly provided you, you can look for free at the presentation by Flanner, et al. (2009), "Integrating Anthropogenic Heat Flux With Global Climate Models." Even more detail is in the companion journal article: Flanner, M. G. (2009), Integrating anthropogenic heat flux with global climate models, Geophys. Res. Lett., 36, L02801, doi:10.1029/2008GL036465. Averaged over the entire globe's surface, anthropogenic heat flux contributed only 0.028 watts/meter^2 in 2005. That's a tiny fraction of the forcing from CO2, which is 2.66 watts/meter^2.
  45. What do the hacked CRU emails tell us?
    Um, the most important word in the email is "hide". If the decline were actually not real(say if it were a statistical artifact), it would not need to be hidden.
    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. So in essence what's happening here is an attempt to graph out what scientists believe to be the best reconstruction of past to present temps they can. Gavin Schmidt agrees that the graph created for the WMO brochure should've been more comprehensively labelled, but this has nothing to do with the science. Mann explained exactly what he did and why he did it in his Nature article. All out in the open, nothing "hidden". The divergence problem is real. As John mentions in his top post, it's been discussed a lot in the literature, and is an area of active research. Denialists - Jeff Id currently is perhaps the most vehement in this view - claim that tree ring proxies can't accurately reflect temperature at all. This is bull. We know that properly situated trees are sensitive to temperature changes due to extensive work into plant (including tree) physiology (and, remember, trees are a valuable agricultural crop so most of this research has had nothing to do with the climate change debate). We also know it is bull because such reconstructions closely match other proxy reconstructions. Also, not all dendro datasets show the divergence problem.
    Is it right to say, then, that the decline needed to be 'hidden' because it was in the case referred to shown by the tree-ring proxy data, which, given your comments about sensitivity, would have been a distortion to include in that case?
    I'd say it's simpler - the decline shown by the tree-ring proxy data over recent decades can't be real because the instrumental record shows it's not real.
  46. High CO2 in the past, Part 2
    #25 DrMike I think you may have misinterpreted the physics a little here: Forcing doesn't "explain away", anything - the basic forcing is relatively well established, and the sum of solar + C02 forcing is comparable to what we are entering into now. Not very much more, not very much less. The feedbacks are not entirely independent of the forcings, but as a first approximation we can assume they are. Therefore, very much higher CO2 in the past is, roughly, balanced by a somewhat weaker sun. The general picture strongly supports the mainstream theory here. Because we lack the necessary data, we can't, now, in any conclusive way use perceived anomalies in the distant past, like the glaciation/lack thereof at a given level of forcing, to refute current theories. And as long as those theories involve feedbacks as the dominating mechanism, we may face principal limitations in what we may prove with some rigor, because of the complexities. On the other hand, we can obtain crude estimates of long-term averages, and, if I am not quite mistaken, these estimates indicate, in general, significant positive feedback. I think this is a reason why the paleoclimatic record is little brought up by people denying AGW: Their claims are not well supported by the available data, and this tends to get worse over time.. I can well understand that you are not convinced, but you have to make a detailed argument building on best available estimates to get much further. As for the main AGW issues, they will be settled, conclusively, over a few decades from now by the large-scale experiment mankind performs on earth, regardless of any unexplained anomalies of the past. I also find your categorization "climate change advocates" a little funny, as long as climate, as defined by long-time trends, (periods longer than combined sun and ocean cycle lengths) is clearly changing. It will, in fact, take quite a lot of cooling to even out the long-time trends so much as to be able to speak of "no change". Because short-time fluctuations of most parameters are, mostly, several times larger than changes by trend, statistics calculated from observations over shorter periods are, generally, unstable and therefore of little value. There is, at present, no question about climate change. The main questions are, how fast, and is it transient or more stable? What are the reasons? How big is the anthropogenic component, and what constitutes it?
  47. An overview of glacier trends
    Thanks Chris. You're right, my question might have been better here.
  48. The albedo effect
    Henry, here is a quick quantification of direct anthropogenic heat production: http://www.realclimate.org/index.php/archives/2009/10/an-open-letter-to-steve-levitt/ Direct anthropogenic heating, even under assumptions favorable to it as an hypothesis, explains very little of the observed energy content increase of the Earth. The Arctic (and other low human density and activity places like mountain tops) is warming much faster than other places, nighttime is warming faster than daytime despite less energy burning at night.... What does this tell you?
  49. High CO2 in the past, Part 2
    #23 drmike I'm no expert in this, but as far as I can see, the low temporal resolution in the CO2 record may hide "shorter time" changes, like the ordovician episode mentioned in the posting. Such changes may also account for de-glaciations. There are a number of references cited in the above comments, I guess they may be a good place to look for (partial) explanations. I also wonder if the feedbacks have been constant over time. Changing feedbacks may explain a lot - remember that the actual warming effect is forcing + feedback, with feedbacks seemingly much larger than forcings, but variable. There's where the correlation you mentioned kicks in, the relationship between CO2 and temperature is "non-deterministic". And while we may estimate the forcings with some certainty, actual feedbacks depend on a lot of factors that we may never know for the distant past. Without knowing more about details, I think it may be difficult to use the known record for refutations of the type: "X amount of forcing did not result in Y amount of glaciation, therefore the theory is disproved". We may have rather delicate balances here, think of a dynamic system with more than one attractor. Just my speculation :-)
  50. Darren Lewin-Hill at 08:29 AM on 22 November 2009
    What do the hacked CRU emails tell us?
    Thanks for this post, John. Is it right to say, then, that the decline needed to be 'hidden' because it was in the case referred to shown by the tree-ring proxy data, which, given your comments about sensitivity, would have been a distortion to include in that case? If so, bad choice of word (though it wasn't being chosen for publication), but no problem for climate science. I, and not doubt other lay readers, really appreciate the clarity of your writing here - Thanks.

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