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Comments 123751 to 123800:

123751. KR at 05:22 AM on 23 February 2010
        Is CO2 a pollutant?
        I've had interesting discussions with friends regarding entropy and the Earth. The energy flow from the Sun at 342 w/m2 enters and leaves - the Earth acts like a pass-through at that macro level. Due to the insulating properties of the atmosphere, local entropic reversal through plant growth, and other effects, the energy level at the surface _appears_ anomalously high. But if you think of the Earth as an energy "bucket", it becomes clear. Incoming energy falls in, an equivalent amount pours out, while the Earth holds a continuously overturning level of energy. What we're looking at with global warming is that the edges of the bucket are getting higher (more insulation), and the level of energy at the surface of the Earth increases. That doesn't change the steady state input/output rates.
123752. carrot eater at 05:20 AM on 23 February 2010
        Is CO2 a pollutant?
        suibhne: The net exchange between surface and atmosphere is in the direction from surface to atmosphere. There is no problem here. Remember my example of the wall at 25 C and the wall at 50 C? Based on your current reasoning, it would be impossible for the 25 C wall to emit any radiation that is then absorbed by the 50 C wall. You've already admitted that such radiation does take place, so now you are arguing against yourself. As your statements are now inconsistent with each other, please clarify an argument. In so doing, show exactly which flow in the Trenberth diagram is objectionable, for which thermodynamic reason.
123753. RSVP at 05:04 AM on 23 February 2010
        Have American Thinker disproven global warming?
        The article states... "Thompson looks at several peer-reviewed analyses examining satellite measurements of outgoing longwave radiation" If "outgoing" simply reflects the raw data of temperature as measured by pointing the detector towards the Earth, it would seem that these curves represent a superposition of both Earth surface and atmospheric radiative emissions. It would seem like what matters is where the extra temperature is coming from. If it is coming from the surface of the Earth, that would support evidence for AGW. But if it is coming from the atmosphere, it would actually imply something a little different, more like a GHG heat conduit effect.
123754. Riccardo at 05:04 AM on 23 February 2010
        Have American Thinker disproven global warming?
        Ubique, a little below the fourth graph: "So the results of three different peer-reviewed papers show that over a period of 36 years, there is no reduction of OLR emissions in wavelengths that CO2 absorb. Therefore, the AGW hypothesis is disproven."
123755. Riccardo at 05:01 AM on 23 February 2010
        Have American Thinker disproven global warming?
        Leo G, that's a good one, really a lot of massaging in the MP3 compression algorithm.
123756. Tom Dayton at 04:57 AM on 23 February 2010
        Did Phil Jones really say global warming ended in 1995?
        TruthSeeker, statistics does not equal science. Statistics is one tool in the scientific toolkit. For example, there are many more aspects of decision theory that are used, than statistics per se. Furthermore, even statistics is not monolithic. You've got your descriptive statistics and your inferential statistics, Bayesian and non-Bayesian,.... Even within inferential statistical tests such as the one Jones was asked about, there are multiple possible tests addressing the same phenomenon. For such a test to bear on a decision about the existence of a trend, that test must be sufficiently powerful to detect a trend of that size against the background of the particular level of noise in that sample of that particular size. The trend in global temperature long has been known to be so small compared to the noise, that a sample of 15 years is unlikely to reach statistical significance at 95% confidence level. That's why climatologists don't often bother looking at samples of just 5 years or 10 years, and only sometimes at samples of 15 years.
123757. Philippe Chantreau at 04:40 AM on 23 February 2010
        Is CO2 a pollutant?
        Suibhne "I understand that you would like me to say that IR radiation is exactly the same as heat but I am afraid that it is not." But that's exactly what you're saying, in fact. You're saying that, because the heat transfer must be from hot to cold (surface to atmosphere), IR radiation from atmosphere to surface can not exist. At all. So, whether you realize it or not, you are indeed saying that IR is heat. Or, at least that's what G&T are saying, and you seem to agree with that. I don't know how to say it so that you understand: the heat transfer happens from the surface to the atmosphere. Do you dispute that? Can you look at Trenberth diagram and see that it is actually what is represented there? If not you are experiencing a fulminant case of Dunning-Kruger syndrome. Nothing anyone can do. As for the entire system, at TOA, there is 342 in and 342 out. KR explains the rest fine.
123758. Leo G at 04:35 AM on 23 February 2010
        Have American Thinker disproven global warming?
        Riccardo @ 17 - {to easy to call data massaging whatever analysis is made on the raw data} TO make comments like this easier for my brain to "get", I try to find an anology in my world. The one that jumped out at me this time was MP3 players. They are able to squeeze so much information onto their drives, by "massaging" the data with an algorithym. Only keeping so much of the "raw" data, then when needed, "putting" it back in place. Anyway this works for me. Keep up the good work, enjoy your posts.
123759. Chris G at 04:09 AM on 23 February 2010
        Visual depictions of CO2 levels and CO2 emissions
        For what it is worth, my understanding is that some of the very early climate models failed to include convection, with the result that arbitrarily high temperatures could come out of them. Indeed, some were even on the wrong side of the triple point of water; it was self-evident that something significant was lacking.
123760. KR at 04:06 AM on 23 February 2010
        Is CO2 a pollutant?
        From the wiki: "In thermodynamics, work performed by a system is the quantity of energy transferred by the system to another due to changes in the external parameters of the system. If these changes happen in a reversible way, then the performed work does not lead to a change of the entropy." "Work can be zero even when there is a force. The centripetal force in a uniform circular motion, for example, does zero work since the kinetic energy of the moving object doesn't change. This is because the force is always perpendicular to the motion of the object; only the component of a force parallel to the velocity vector of an object can do work on that object. Likewise when a book sits on a table, the table does no work on the book despite exerting a force equivalent to mg upwards, because no energy is transferred into or out of the book." Work requires a NET TRANSFER of energy. A balanced thermodynamic system does no work, even if energy (carried by IR, convection, conduction in the current discussion) flows both directions between those systems. In this regard the atmosphere is our table, the earth is our book - force is applied, no work is done, but the steady state condition is that the book is off the floor. Heat flow/entropy delta (net change) is zero for a steady state thermodynamic condition, energy flow isn't. Stop willfully confusing net entropy changes (heat) with balanced energy flows. Now if the steady state condition is disturbed (more CO2 blocks more long wavelength IR, more insulation) steady state temps on the surface will change to a point where the net energy flow is again zero (a hotter surface that radiates enough to compensate for the insulating properties of the atmosphere). Heating and cooling are directly reversible, and hence no change in entropy occurs (see first quote). suibhne, you've repeated yourself multiple times with that error about heat flows. It's not heating in a steady state system, regardless of non-zero bidirectional energy flows; no work is done.
123761. Ubique at 04:05 AM on 23 February 2010
        Have American Thinker disproven global warming?
        John: "The American Thinker article does not disprove the greenhouse effect." Agreed - but as I read it, it does not set out to try and do so. What it does is seriously challenge the hypothesis that "... Increased emission of CO2 into the atmosphere (by humans) is causing the Earth to warm at such a rate that it threatens our survival." The issue it addresses is one of magnitude is it not?
123762. Chris G at 03:57 AM on 23 February 2010
        Visual depictions of CO2 levels and CO2 emissions
        theendisfar, I'm familiar with the concepts of evaporative cooling, latent heat, PV=nRT, and all that good stuff. However, for instance, evaporative cooling, is a transfer of energy, it does not cause the energy to cease to exist; since the air and water are still both within the earth system, evaporation does not, by itself, remove energy from the earth. And, entropy does not say that energy will take the least resistant path to the exclusion of all others.
123763. Riccardo at 03:38 AM on 23 February 2010
        Did Phil Jones really say global warming ended in 1995?
        TrueSeeker "First, the significance of Jones statement is that you cannot, scientificly, make the conclusion that there has been heating from 95-2009." This claim is utterly wrong. You cannot determine a stistical significant trend if you limit the period to 1995-2009. But still, you can scientifically make conclusions on this period if you expand the time range. You could also use the period before that, extrapolate the trend and the confidence interval and see if the data from the following period are still inside the limits. We can draw the scientifically sound conclusion that from the '70s up to now there has been a statistically significant trend and also that it is reasonably well aproximated by a straight line.
123764. suibhne at 03:16 AM on 23 February 2010
        Is CO2 a pollutant?
        carrot eater KR CBDunkerson Philippe Chantreau It is impossible for HEAT to flow from a lower temperature atmosphere to a higher temperature planet unless work is done on the system to make it possible. This is not a wild throw away remark but is the settled view of the Physics community. It would make more sense if you would say explicitly that CO2 and water vapour are a machine that works on the atmosphere to pump heat to the surface from the atmosphere. This would then take the discussion back to other familiar situations and conclusions could be drawn. I understand that you would like me to say that IR radiation is exactly the same as heat but I am afraid that it is not. More interesting is the news that there is perhaps a peer reviewed article addressing the same area as the G&T paper. Perhaps the publication of this paper will move the discussion on.
123765. Dikran Marsupial at 03:14 AM on 23 February 2010
        Did Phil Jones really say global warming ended in 1995?
        TruthSeeker @ 100 Nobody is using the trend from 95-2009 as evidence for global warming, laregly because the timescale involved is too small to average out the effects of internal climate variability due to things like ENSO. See the paper by Easterling and Wehner mention in posts 24,37 and 38. It is seen in model output as well. ISTR tamino had a good example on his blog where he made a time series composed of noise plust a linear trend. It was possible there to find periods of cooling, even though the signal *by construction* had a constant rising linear trend. Also the enhanced greenhouse effect *does* suggest that Earth's total heat content will rise, as it puts the planet out of radiative equilibrium, which won't stop until the radiating layer warms up to the point that a new balance is reached. That does not mean though that in the short term exchanges of heat between oceans and the atmosphere can't result in warming oceans and cooling atmosphere; there is still an increase in heat overall content.
123766. Philippe Chantreau at 03:13 AM on 23 February 2010
        Is CO2 a pollutant?
        G&T are the ones trying to obfuscate things by equating IR radiation and neat heat, and you swallowed it hook, line and sinker. I'll quote myself: "heat flows from the surface to the atmosphere." That's a short, albeit accurate summary of the Trenberth diagram and I'm very confident that thermodynamics are on my side with this statement, you disagree? It does not prevent some IR radiation from flowing between atmosphere and surface. You can disagree with that if you want but I'll still trust the instruments measuring it and calculations showing it. You've been asked repeatedly to show where the Trenberth diagram violates any TD law. You keep on saying it does without having provided an answer. You have nothing of interest to say.
123767. Riccardo at 02:44 AM on 23 February 2010
        On the reliability of the U.S. Surface Temperature Record
        TruthSeeker, much easier indeed. Stations at high latitude have shown on average a lareger increase in temperature. The effect of removing those stations would be a reduced anomaly. Remember, anomaly is not absolute temperature. Also read my comment just before your if you prefer the opinion and the "massaging" of the data of an old time skeptic.
123768. Riccardo at 02:33 AM on 23 February 2010
        Have American Thinker disproven global warming?
        TruthSeeker, to easy to call data massaging whatever analysis is made on the raw data. Do you really think that cutting edge science is made with just a thermometer, a tape meter and a screwdriver? Do you think that you can just fly a satellite and it will say "hey, this is the number you were looking for"? It's silly. Look around other scientific fields or even what is behind many technological applications and you'll find even more data "massaging" than in Harries paper.
123769. theendisfar at 02:30 AM on 23 February 2010
        Visual depictions of CO2 levels and CO2 emissions
        Chris G, http://en.wikipedia.org/wiki/Evaporative_cooler http://en.wikipedia.org/wiki/Latent_heat While it takes 99 joules to raise 1 gram of water 99 C, it takes an additional 2260 joules to get it to change from a liquid to a gas. This seems odd given that our oceans are not boiling yet we have a great deal of water vapor in the atmosphere. so let's put it another way. It doesn't not take 2260 joules to vaporize a gram of water. The second link provided gives a satisfactory explanation as to why.
123770. TruthSeeker at 02:22 AM on 23 February 2010
        On the reliability of the U.S. Surface Temperature Record
        Excellent write up. I accept the argument as presented and it has changed my opinion on the subject. I now agree with the premis that Heat Islands are not responsable for recording increased temperatures. What about the criticizim that their has been a reduction in temperature stations over time, and that the ones being excluded are sites that have been historically recording "cooler" temperatures than the average. It seams it would be easy to prove or disprove that one.
123771. Riccardo at 02:19 AM on 23 February 2010
        Climategate CRU emails suggest conspiracy
        Argus, did it never happen to you to say in a private conversation "if he does this i'm going to kill him" or "i love this thing, i'm going to steal it" or something like this? Wow, that's incredible.
123772. TruthSeeker at 02:17 AM on 23 February 2010
        Did Phil Jones really say global warming ended in 1995?
        Dude, This is the worst argument that you have ever made. First, the significance of Jones statement is that you cannot, scientificly, make the conclusion that there has been heating from 95-2009. That is scientific fact. This is in direct conflict with the fact that CO2 rates have continued to rise in that same time frame. Second, what is with this Heat Content argument? It is nothing more than a distraction. The orginal premis of the whole global warming "problem" is based on temperatures that will continue to rise, and this is not the same as heat content rising. If I have a pot of cold water, and supply it with a temperature of 101 C. the pots heat content will continue to rise, but the applied temperature stays the same.
        Response: I have to disagree with you there - I've made worse arguments on several occasions (finding those instances I leave as an exercise to the reader).
        
        I go into more detail about why heat content is a more appropriate metric for measuring global warming than surface temperature on the global cooling page. The land and atmosphere are only one small fraction of the Earth's climate (albeit the part we inhabit). Global warming is by definition global. The entire planet is accumulating heat due to an energy imbalance. The atmosphere is warming. Oceans are accumulating energy. Land absorbs energy and ice absorbs heat to melt. To get the full picture on global warming, you need to view the Earth's entire heat content.
        
        That's not to say surface temperature is unimportant. But by looking at surface temperature in proper context, you can see why it shows so much variability - it is a small part of a climate which exchanges heat between its various components such as the ocean exchanging heat with the atmosphere. We mustn't forget that global warming isn't just about graphs and statistics - it's the physical reality of the planet steadily accumulating heat due to an energy imbalance.
123773. theendisfar at 02:09 AM on 23 February 2010
        Visual depictions of CO2 levels and CO2 emissions
        Let's suppose (in the worst case) every ounce of IR energy were absorbed within a few meters. This would simply raise the radiative heat source a few meters off the ground... or is the energy just going to stay there forever hovering over the ground? That would be on average 240 W/m^2. For dry air, it takes ~1,300 joules to raise a cubic meter of air (1.3kg) 1 degree C. So it will take approximately 5 seconds to raise the temp 1 C. As the temperature of that cubic meter of air increases, its density decreases and moves the heated volume skyward to be replaced by a lower temp volume of gas (nature abhors a vacuum) and the process repeats. As the volume rises, pressure decreases and so does the temp from PV=nRT. It takes energy to move that volume of gas, in fact it takes ~88,000 Watts to move a 1 m^2 column of dry air 1 meter/sec skyward. The Earth only radiates at 240 Watts, which makes sense given that Radiation is the least efficient means to transfer energy while convection is very efficient. Entropy states that energy will take the path of least resistance or the most efficient path. Once Convection is no longer available as a means to transfer energy (i.e. Tropopause), then Radiation becomes the only means of cooling. Note that the Earth's convection zone, the troposphere, would only be 8 mm high if the planet was 100 meters in diameter. While that is a very short distance, convection moves massive amounts of energy within that zone. The wind that drives sailing vessels has huge amounts of force behind it. That energy comes from convection, which comes from the surface heating the air just above it.
123774. KR at 01:53 AM on 23 February 2010
        Is CO2 a pollutant?
        suibhne: Once again you mistake the tree for the forest. Simple black body radiation (yes, simplifying for this discussion) emits from any object at levels corresponding to temperature. The Earth radiates the ~390 w/m2, plus another 100+ or so in conduction/evaporation. [Note that the measured bidirectional energy flow is 4x higher in radiation than conduction/convection.] The atmosphere radiates 342 (note, less!) towards the Earth. That and the 168 solar irradiance sum to (wait for it) 0. That's important, suibhne, _zero_. This is a steady state thermodynamic balance, and WORK is not being done. The atmosphere bounces a great deal of the energy emitted by the earth right back to it (like a silvered thermal blanket) - no work is done, just a different steady state condition than with no atmosphere. You have again argued from a portion of the equation, not the sum; looking at a part of the energy flows rather than the summation. As for the Earths surface being warmer than space, the solar irradiance impinges on the earth, lower wavelength/lower energy (IR) is emitted (simple entropy there, the earth isn't a perfect mirror), and CO2 with an IR absorbance peak retains it. Enough said. You first need to look at the summations in the steady-state thermal diagram, and realize that if work is being done it wouldn't be steady-state. Second, "It is impossible for HEAT to flow from a lower temperature atmosphere to a higher temperature planet unless work is done on the system to make it possible" realize that the presence of something warm (the atmosphere) keeps neighboring things warm (the Earth) by slowing/balancing energy emission rates. Again, this is a summation of all energy flows. And third, the energy flows of IR, conduction, and evaporation are easily measured and known - the GT assertions apparently denying IR energy exchange to the contrary are simply and provably wrong. I realize this isn't the last word on the topic; I assume that you will have some response. However, this is the last that I will post unless you have an actual and substantive point.
123775. theendisfar at 01:42 AM on 23 February 2010
        Visual depictions of CO2 levels and CO2 emissions
        Alexandre, Why thank you! I welcome your assistance, for starters though, let's just begin with ONE formula and as many coefficients as required. Your language suggests you have a superior understanding or was it condescending in nature. I would like to find out.
123776. carrot eater at 01:29 AM on 23 February 2010
        Is CO2 a pollutant?
        suibhne Finally, you've decided to explicitly accept the G&T position. OK. Now, where in the Trenberth diagram is heat flowing the wrong way, suibhne? Please point out exactly where the wrong way transfer is.
123777. CBDunkerson at 01:26 AM on 23 February 2010
        Is CO2 a pollutant?
        Actually, both the discovery of the greenhouse effect and thermodynamic laws were first announced in 1824. However, the problem here isn't that the greenhouse effect violates the laws of thermodynamics... it is that you don't understand those laws. As you are attempting to apply them the Earth could be no warmer than the temperature generated by incoming solar radiation... yet it is ~32 C warmer. The planet is NOT a solid ball of ice. Ergo, your understanding MUST be incorrect. How is that possible? Well, for starters you are trying to determine entropy while leaving the energy SOURCE (i.e. the Sun) out of your system of observation (atmosphere and planet only).
123778. danielbacon at 00:53 AM on 23 February 2010
        Have American Thinker disproven global warming?
        http://www.eumetsat.int/.../pdf_conf_p50_s9_01_harries_v.pdf I think this is the newer study to the (Harries 2001). If it is the place it above and delete my post thanks.
123779. Dennis at 00:45 AM on 23 February 2010
        Have American Thinker disproven global warming?
        Remember last weeks postings on the Dunning-Kruger effect? Well, Gary Thompson's writing is a perfect example of it.
123780. Arkadiusz Semczyszak at 00:01 AM on 23 February 2010
        Have American Thinker disproven global warming?
        It seems to me, that the main theme here is "skepticism" about the American Thinker, not only "Longwave radiation" ... Is so surely my earlier (deleted) comment was not about what You write?
        Response: That comment was deleted because it was off-topic - it seemed to come out of left field and I struggled to see what it had to do with the discussion at hand. I'd say it was more appropriate in a discussion of what's causing the rise in atmospheric CO2.
123781. suibhne at 23:50 PM on 22 February 2010
        Is CO2 a pollutant?
        CBDunkerson It is impossible for HEAT to flow from a lower temperature atmosphere to a higher temperature planet unless work is done on the system to make it possible. Why do you think that every Physics or Thermodynamics textbook would back me up on this? The laws of thermodynamics were there before and after any supposed new theory such as Greenhouse theory. They can not be set aside.
123782. Arkadiusz Semczyszak at 23:38 PM on 22 February 2010
        What would happen if the sun fell to Maunder Minimum levels?
        HumanityRules My comment is a little late, but ... - Warming, e.g. in the Older Peron - was global, but higher in NH. The current warming is also greater for NH. Responsible for changes in the THC - North Atlantic deep - below the shelf - narrows the "bottleneck" ... The spectacular example - most of Antarctica, over the past 35 years, is cooled (http://www.sciencedaily.com/images/2008/05/080507132855-large.jpg), which is typical for the Millennium cycles, although the reasons may be Miscellaneous (e.g.: "A doubling in snow accumulation in the western Antarctic Peninsula since 1850." E.R. Thomas et. al., Geophysical Research Letters, VOL. 35, L01706, doi: 10.1029/2007GL032529, 2008).
123783. CBDunkerson at 23:27 PM on 22 February 2010
        What would happen if the sun fell to Maunder Minimum levels?
        AndrewY, assuming that you are referring to Figure 2... it should be understood that the sharp dip shown 'coming up' is the result of a randomly placed major volcanic eruption (as can be seen by the corresponding downward spike in the black line at the top of Figure 3). Thus, while a volcanic eruption could happen in that time frame and have that sort of short term cooling impact, there is no scientific data suggesting that this WILL happen... our ability to predict volcanoes is extremely limited. The random eruptions were included only to show that they have little impact on the long term trends. That said, your observation about short term fluctuations testing "faith in science and reason" is very much what we've been living through this past decade of only mild warming. If it, and the accompanying denial, continued we could very well miss our chance to stop GHG emissions from reaching dangerous levels. However, that seems unlikely to be the case... predictions for the current year suggest that it is going to have a high temperature anomaly. Indeed, last month was the hottest January ever recorded and the third highest anomaly month (after two in 1998) in the UAH records. February looks on track to be similarly high. If predictions for 2010 hold out then it is likely that carefully constrained 'no statistically significant warming since 1995' bit will go poof.
123784. Ned at 23:09 PM on 22 February 2010
        Have American Thinker disproven global warming?
        HumanityRules, I think it's great that you're asking so many questions. My question to you might require a little introspection. I don't know whether you had seen the original post about this graph at "American Thinker," but if you had, would you have put in a comparably aggressive effort to question Gary Thompson's representation and conclusions? In other words, are you this skeptical towards claims on both sides of the issue, or only in one direction? Perhaps you would have ... but if so, you would have been pretty much alone among Mr Thompson's audience. I didn't read through all the comments over there, but I did examine the first 20 posts. Not a single one raised any questions about Gary Thompson's mis-representation of the paper. Instead, here is a summary of those 20 comments:
        • Expressing congratulations: comments 1, 2, 12, 15, 18, 20
        • Promoting conservative political agenda: comments 2, 4, 7, 8, 10, 11, 12, 14, 17
        • Attack on scientists: comments 3, 5, 7, 9, 10, 13
        • Statement that AGW is a hoax/fraud/scam: comments 10, 11, 13, 14, 17
        • References to Al Gore: comments 7, 11
        • Praise for Lindzen or other prominent "skeptics": comments 9, 10, 15
        • Linkage to other climate-"skeptic" issues: 13 (snow this winter), 18 (claims of ice age in 1970s), 19 (Medieval Warm Period, hockey stick, etc.)
        • Linkage to other issues: comments 10, 17 (both advocating use of DDT as a pesticide)
        In other words, there's a complete absence of skepticism over there. Indeed, there's little more than self-congratulatory backslapping, repetition of widely available "talking points," and a tendency to see everything in the light of a particular current US conservative political agenda. Whatever your position on AGW is, one should at least acknowledge that John Cook has done an admirable job of creating a site here where science is discussed openly and critically, and where politics and personal attacks are mostly left outside.
        Response: After posting this article, I was a bit annoyed with myself that I forgot to read the comments on the American Thinker article - there may have been someone who raised similar objections and hence the author's response would've been interesting. If all comments were similar to the first 20, I'm glad I didn't waste my time.
123785. HumanityRules at 21:50 PM on 22 February 2010
        Have American Thinker disproven global warming?
        Whoops my bad. They do mention the 1997 El Nino but not the 1970 La Nina. Still not so happy with the one liner suggesting it may just shift the base line. The reversal of the trade winds during these two periods is surely going to have a major impact on the atmosperic components over the Central Pacific and elsewhere.
123786. Argus at 21:33 PM on 22 February 2010
        Climategate CRU emails suggest conspiracy
        Riccardo : '' None of them ever said they were going to delete the email.'' Maybe not, but this quote is rather close (from Phil Jones). Close enough for me!: ''If they ever hear there is a Freedom of Information Act now in the UK, I think I'll delete the file rather than send to anyone...''
123787. AndrewY at 21:30 PM on 22 February 2010
        What would happen if the sun fell to Maunder Minimum levels?
        First, thanks a lot, John, for your work on this site, it is a great resource and your writing is clear, accessible and objective. I have to say that I see a very worrying feature in this prediction of the global temperature anomaly. In all cases there is a brief rise and then a considerable decline in the global temperature over the next decade. After that (from around 2020) the global temperature climbs very rapidly. This is presumably because natural climate variation/cycles first hold back the global warming trend, then after 2020, combine to reinforce it. I realise that climate models don't predict these relatively short term trends very well, but if this temporary reversal of the warming trend actually happens in this decade, it will make it a lot more difficult to convince politicians and the public that global warming is a serious problem that requires radical changes to the way we generate and use energy (and resources). How terribly ironic if such a temperature decline actually happens just at the time when a concerted effort to reduce GHG emissions is most vital! It will truly test humanities faith in science and reason.
123788. Riccardo at 21:22 PM on 22 February 2010
        Have American Thinker disproven global warming?
        HumanityRules, 1) no, different absorption bands have different strength. As you can easily see in panel a, the band at 970 cm-1 is minuscule. The difference is scaled proportionally so is minuscule as well. 2) From the paper: "All the principal features due to changes in CO2, CH4, O3, temperature and humidity are well modelled, as are the small changes due to the chlorofluorocarbons (for example, at 850 and 920 cm-1) and weak CO2 bands (for example, at 795 cm-1)." It appers that John actually read the paper. 3) didn't understand what the point is. 3) this paper shows the increasing absorption of CO2 and other GHG. This is unambiguous whatever H2O might have done. The conclusion that it "[...] is consistent with concerns over radiative forcing of climate" is appropiate.
123789. 70rn at 21:15 PM on 22 February 2010
        Have American Thinker disproven global warming?
        @7 The absorption regions used these graphs - specifically the ones between 700 - 800 cm^-1, are not attenuated by h2o and as such change at that range in the spectrum cannot be attributed to it. Below 700 cm^-1 the absorption regions of co2 and h20 begin to overlap, so change in that region can be correlated to co2 alone. Point 2. There is no co2 absorption range at 970 cm^-1 that i am aware of, though i believe there to be a 03 region somewhere there about.
123790. Pierre-Normand at 21:15 PM on 22 February 2010
        Have American Thinker disproven global warming?
        I had posted a comment on JREF regarding this Smoking Gun. It's not so very often that I can be ahead of SkepticalScience!
        Response: It's not that hard to get the scoop on me - I'm hardly known for my promptness or punctuality :-)
123791. HumanityRules at 21:07 PM on 22 February 2010
        Have American Thinker disproven global warming?
        Another question. Is the Central Pacific data comprimised by the fact that Apr-Jun 1970 was the start of one of the strongest La Nina this century while Apr-Jun 1997 was the start of one of the strongest El Nino. There is no mention of this fact in the Nature paper.
123792. 70rn at 20:50 PM on 22 February 2010
        Have American Thinker disproven global warming?
        I may be foolish to ask such a question, but what does brightness temperature actually mean. Is n brightness temperature (K) equivalent to the amount of energy necessary to create a change of n °s K, per wave-number cm ^-1? And if so can you relate such changes (obviously not directly to surface temperature over the same period? The lack of data below 700 cm ^-1 is not so surprising as there is overlap with water vapour beyond this point and as such it may be more difficult to detect changes. A thought, atmospheric circulation is more complex further away from the thermal equator, and energy/temperature cycling is more dependent upon atmospheric movement than at lower latitudes. Is it possible co2 has a greater effect in part because of this?
123793. CBDunkerson at 20:45 PM on 22 February 2010
        Is CO2 a pollutant?
        Suibhne wrote: "You seem to insist that HEAT flows from a lower temperature atmosphere to a higher temperature planet. No Physics or Thermodynamics textbook will support you in this." This central argument in the G&T paper is, evidently, an article of faith on which you will not be swayed. It is however clearly false. As has been shown in countless examples to the contrary. Were it true the 'effective temperature' and 'actual temperature' of all planets would be the same (and Earth a large ball of ice), two heat lamps in close proximity would result only in the cooler one warming while the warmer one is magically unaffected by the other heat source, those reflective space blankets wouldn't work because they are colder than the human body they are applying heat to, and so on through the various thought experiments you have been unable or unwilling to follow.
123794. HumanityRules at 20:38 PM on 22 February 2010
        Have American Thinker disproven global warming?
        I'd be interested in your questions to the author and his replies mainly because if there is a small critisism I have of your presentation of publications that support AGW it's that you under-represent the limitations of the work. For my part there would be a couple of questions. 1) Figure 2 also has a third graph (c) which shows CO2 absorption around 970cm-1 but there appears no difference in the 1970 and 1996 data. Is this an issue? 2) I'd just query whether you too are seeing what you wish to see in the same way that the American Think guy is. On the 2b graph you state that the top and middle graphs show strong agreement. Are you making this statement based on eyeballing the graphs? Because in the 700cm-1 region the observed difference seems smaller than the modelled difference for the central pacific. 'Observed - model' would be useful here because deviation from the model actually looks significant at the important 700cm-1 wavelength compared which much of the rest of the graph. 3) Is there any problem associated with a ten-fold difference in the data points from 1970 and 1996? While they describe the process for discarding unreliable data and state the absolute numbers of data points used for each time point they don't state what % of data is thrown away for each time point. Is the tenfold difference due to data collection or data rejection? If you are rejecting 50% of the 1996 data but 95% of the 1970 data you'd have to worry what effect this is having on results. 3) Given that the author makes the following statement "But this relationship is complicated by several feedback processes - most importantly the hydrological cycle - that are not well understood" And the author also aknowledges that changes in atmosperic ice would give a result indistinguishable from the observed results shouldn't there be a huge rider on the interreptation of the results. Since H2O has to be ignored in this and it is the most potent greenhouse molecule shouldn't the conclusion just be that we are unable to rule out CO2 having a greenhouse effect and save final judgement for when we do better understand the role of water in all of this?
        Response: Here are the questions I sent (italic) and John Harries' responses (JH). Very prompt and very detailed, he's a class act:
        
        JC: I was curious as to why the comparisons of spectra only went down to 700cm-1 when the IMG data went down to 600cm-1. It seems there would be more CO2 absorption at lower wavelengths.
        
        JH: The signal to noise ratio below 700 cm-1 decreased rapidly, so the quality of the spectra below this point was not good. The error bars became larger than the expected differences, so this region was not used.
        
        JC: How did you work out the difference between the IMG to IRIS data?
        
        JH: For the observations, measurements from both the IRIS and IMG instruments are available. These were calibrated radiometrically by the scientific teams that carried out each project. We had to process the data so that the spectral resolution was the same (choosing the resolution of the lower resolving instrument - IRIS), and we tested that the data processing in each case had not introduced artificial differences (apodisation function, field of view), and that the spectral scales were equalised (comparison of spectral wavenumber of individual features). Once all these effects had been taken into account, so that the two spectra were directly comparable, we took the difference to produce Figs 1a and 1c. For the theoretical curve (Fig 1b), we have programs that can simulate the upwelling spectrum at the top of the atmospehre, if the state of the atmosphere below is defined. We have data for the atmosphere for both periods, for the location chosen, and so these data were input into the program, and two spectra generated. The difference between these two spectra produces the difference spectrum betwen 1970 and 1997. Note that the theory curve confirms that the shape of the two observed difference spectra in the CO2 band is correct.
        
        JC: I was wondering if your analysis determined whether the total amount of outgoing longwave radiation had decreased from IRS to IMG? If so, is it mentioned in any of your papers (I couldn’t find anything but I may have missed something)?
        
        JH: It's a good question. The problem is that the observations do not cover the whole of the outgoing spectrum, and so it is impossible to obtain a total integral across all wavelengths. The 'missing' part of the spectrum is mainly at lower wavenumbers than about 500 cm-1, where there are effects due to the water vapour feedback.
        
        Even if we could integrate the whole of the outgoing IR, there is still the shortwave (SW) side of the net radiation balance, which we would need to consider to look at the total energy change, in and out.
        
        One other point: to sum up all the energy you would have to use the radiance spectrum, not the brightness temperature spectrum. Though they are equivalent, the transform from one to the other is not linear. So, integrating brightness temperature would not be easy to interpret.
        
        At present, therefore, the spectral measurements are not available to do the integration you suggest, which is why you found no mention in my papers. If you are interested in understanding any changes in the measured incoming and outgoing radiation, the best approach is to use the broad-band (non-spectral) Radiation Budget measurements from instruments such as NASA's CERES.
123795. Steven Sullivan at 20:26 PM on 22 February 2010
        Did Phil Jones really say global warming ended in 1995?
        George Will is at it again. Ugh. "Global warming skeptics, too, have erred. They have said there has been no statistically significant warming for 10 years. Phil Jones, former director of Britain's Climatic Research Unit, source of the leaked documents, admits it has been 15 years. " http://www.washingtonpost.com/wp-dyn/content/article/2010/02/19/AR2010021903046.html
123796. stevecarsonr at 20:22 PM on 22 February 2010
        Have American Thinker disproven global warming?
        Nice article. Most people have only the haziest notion of what radiative effects take place in the atmosphere. So any story sounds plausible. In fact, lay out the actual basic facts of longwave upwards and downwards flux at the surface and at top of atmosphere and there will be a lot of people telling you that you are wrong, the numbers are wrong, it breaks the laws of physics, you are mixing up shortwave radiation, and so on.
123797. Riccardo at 20:11 PM on 22 February 2010
        Have American Thinker disproven global warming?
        eyeballing + accurately choosen graph = demonstrate almost anything Try yourself, is a funny game to play with friends.
123798. suibhne at 19:24 PM on 22 February 2010
        Is CO2 a pollutant?
        Ned carrot eater Philippe Chantreau KR You seem to totally ignore the atmospheric insulation provided by conduction and convection effects. The wind and tides redistributing thermal energy around the planet. Geothermal effects, resistive effects, wave thermal effects, in keeping the planet warm. Overemphasis on radiation, will distort the reality of the situation.
123799. suibhne at 19:14 PM on 22 February 2010
        Is CO2 a pollutant?
        Ned carrot eater Philippe Chantreau KR You seem to insist that HEAT flows from a lower temperature atmosphere to a higher temperature planet. No Physics or Thermodynamics textbook will support you in this. However if you say that co2 and water vapour form a machine to do work on the atmosphere then at least we could look into that. As far as I know no body is prepared to be as explicit as this.
123800. Stuart at 19:13 PM on 22 February 2010
        Have American Thinker disproven global warming?
        Now this is just embarrassing. The "skeptics" continue to let the blind lead the blind.

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