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Comments 123551 to 123600:

123551. Riccardo at 03:35 AM on 24 February 2010
        Have American Thinker disproven global warming?
        guinganbresil, you have to think in terms of a time dependent process. Separate, at first, the two contribution, energy absorbed by increasing CO2 and energy emitted by the warming surface. Both increase monotonically. When you start adding CO2 the first term must prevail pushing the system out of equilibrium. Then the system responds increasing its temperature. Two cases need to be considered: 1) if the increase in temperature is not strong and/or fast enough, absorption keeps prevailing pushing the system further and further out of equilibrium. This is the "pathological" case of the runaway warming. 2) if the increase in temperature is able to keep up with the forcing, the trend in total OLR reverses and the planet will exponentially reach a steady state. The take away message is that in any reasonably real situation on planet earth, if you measure a decreasing OLR the planet might be going toward a runaway warming or at least it's too early to tell (remember, it's a time dependent process); if you measure increasing OLR the planet is going to reach a steady state. Luckly the latter applies to the current situation and at least for now we can rule out runaway warming.
123552. Rob Honeycutt at 03:25 AM on 24 February 2010
        A brief history of our iPhone app
        Just downloaded the iPhone app yesterday. It's fantastic. I find myself just sitting and reading through the segments. I have a few climate change denier friends. This should make for great fun at our next party.
123553. Tom Dayton at 03:23 AM on 24 February 2010
        What would happen if the sun fell to Maunder Minimum levels?
        Cowboy, your quote of NOAA is specifically about stratospheric temperatures, not the rest of the atmosphere nor the average of the atmosphere. Volcanoes emit both CO2 and aerosols (some reflective and some not). The precise effects on temperature vary over time for a given volcano, and vary across volcanoes, because of variation in the amounts and rates of those emitted substances, and how high in the atmosphere they go (and even the height changes over time). For more, see the Scientific American note How Do Volcanoes Affect World Climate? If you have more comments about volcanoes, you should post them on a thread about volcanoes, such as Volcanoes emit more CO2 than humans. Our host, John Cook, is trying to keep each thread on topic, so often he deletes off-topic comments.
123554. Tom Dayton at 03:04 AM on 24 February 2010
        What would happen if the sun fell to Maunder Minimum levels?
        Cowboy, many questions are addressed in the list of "Arguments" you see at the top left of this page (the ones next to the thermometer). See, for example, CO2 lags temperature. Also handy for finding the relevant arguments and posts is the Search field at the very top left.
123555. stbloomfield at 02:21 AM on 24 February 2010
        A brief history of our iPhone app
        Android please! My Motorola Cliq has had iPhone envy since you released your app!
123556. Dennis at 02:21 AM on 24 February 2010
        A brief history of our iPhone app
        Alas, I do not have an iPhone. (With a dirt cheap pay-as-you-go plan, I barely qualify as a cell phone user.) but if I did I would add this app. Let's see if the followers of Climate Realists come out with their own app. What will be interesting will be to document their "evidence" and break it down between actual science and politics/conspiracy drivel.
123557. RSVP at 02:04 AM on 24 February 2010
        Have American Thinker disproven global warming?
        "Riccardo at 06:00 AM on 23 February, 2010 RSVP, the continuos part of the spectrum comes directly from the surface and reflects surface temperature. The atmosphere is overall much colder, i.e. much lower emission intensity and a peak shifted to lower wavenumbers, and being almost transparent has a lower emissivity. On the contrary, the level at which the strong absorption bands saturates reflects the tropospheric temperature or, to be more precise, the air temperature at the height from which IR escape directly to outer space. " I am sorry, but I do not follow. I thought CO2 is making the atmosphere that much warmer? Here you are saying it is colder, and that the extra IR is coming from the Earth's surface. If this energy is escaping because the atmosphere is transparent at these wavenumbers, how exactly is the surface getting warmer? If I am skeptic about anything, it has to do with my faith in "believers of AGW" to make a convincing argument about AGW. I think it would be more productive if we all just concentrated on lower CO2 for other reasons.
123558. guinganbresil at 00:27 AM on 24 February 2010
        Have American Thinker disproven global warming?
        Tom Dayton (40), may assertion is based on conservation of energy. If you SUDDENLY add insulation to an object that is in thermal equilibrium, the heat loss from the object SUDDENLY goes down. The object's temperature then increases (and its heat loss through the new insulation) to restore the equibrium to the original heat loss. Conservation of energy would prohibit both the heat loss AND temperature to increase at the moment you add the new insulation unless the insulation were creating (or adding) energy to the system. The heat loss has to DROP before the temperature can increase. The more realistic case is a continual adding of insulation (increasing CO2) rather than a step increase. In this case the same applies, the increase in heat loss would only occur after the addition of insulation has been reduced (or stopped as shown in Murphy 2009.) At best, you could achieve a state of quasi-equilibrium where the increase in temperature (and thus its contribution to heat loss) matches the decrease in heat loss from the increasing insulation. I agree with you that IN REALITY the OLR could be going up due to some cause OTHER THAN CURRENT CO2 INCREASES - changes in albedo, insolation, or recovery from a PAST high CO2 transient that has been reduced. I have not seen a good explanation of the disparity. The increasing CO2 cannot warm the Earth (with downward long wave) if it is causing more heat loss to space (upward long wave) unless it is GENERATING ENERGY. I understamd the wavelength bands of the specific upward and downward fluxes are different, but overall energy must be conserved.
123559. RSVP at 21:18 PM on 23 February 2010
        Have American Thinker disproven global warming?
        garythompson "We have increased the CO2 in the atmosphere about 17% from 1970 to 2006 (328ppm vs. 383ppm) and the OLR appears to have remained constant" John Cook "Anyway, I appreciate your comments and expect (nay demand) that commenters here will abide by our commenting policy and treat you with respect." As long as the debate is focused on whether CO2 is causing global warming or not, oil interests are off the hook. Ironically, those who are crusading for the planet's health (in terms of correlating warming to GHG emissions) are in some sense impeding that attention be focussed on what is directly measurable... that being anthropogenic CO2. Of concern specifically is the planet's capacity to absorb CO2, and where all this could be taking us. This may be more of a problem than any warming. I dont really know this, but somehow if anything has me genuinely concerned, it is not runaway global warming, but runaway global CO2 concentration. I have placed these two excerpts side by side to contrast what appear to be two realities. One reflecting a known. The fact about CO2 global levels (even though I arrived at 14% using these values). The other, John's need to mediate the hubris of those "in the know". I would go further still and ask what guarantees does proving AGW have on taking action against curbing CO2 emissions? Maybe the warming will be seen as necessary as temperatures actually start dropping for other "radiative forcings". On the other hand, focussing directly on the ills of CO2 and our ability to control its output seems like enough work in its own right. ETC.
123560. Dikran Marsupial at 19:48 PM on 23 February 2010
        What would happen if the sun fell to Maunder Minimum levels?
        Cowboy asks: "But isn't the theory of "greenhouse gases" that solar energy is absorbed by gases in the atmosphere? " I think it would be more correct to say that greenhouse gasses absorb the long wave radiation (i.e. heat) leaving the Earths surface, rather than the incoming short-wave solar radiation (light). w.r.t. CO2 lagging temperatures, a change of concentrations of about 100ppm (as we have seen over the last 200 years) happens at the start start of an interglacial period. This results from a temperature change of about 6 degrees or more, so you could argue there is a sensitivity of about 20 ppm per degree. There simply hasn't been a temperature change in the last few thousand years that could explain a rise of 100 ppm, so for that theory to work, you would need to find a reason why the carbon cycle is 6-10 times more sensitive to temperature now than it has been for the last 800,000 years (looking at the Vostok ice core data). Since the industrial revolution, CO2 levels have been rising at a fairly constant fraction (about 45%) of human emissions (fossil fuel + land use), which is prettty good evidence that the cause of the rise is not a lagged response to previous warming, but is the result fo human activity.
123561. Cowboy at 19:41 PM on 23 February 2010
        What would happen if the sun fell to Maunder Minimum levels?
        Sorry to double-up on posting (I'm not a spammer), but with respect to the few posts above, I just found this at NOAA... "While middle tropospheric temperatures reveal an increasing trend over the last three decades, stratospheric temperatures (14 to 22 km / 9 to 14 miles above the surface) have been below average since the warming effects from the 1991 Mt. Pinatubo eruption dissipated in 1993. January - December 2008 was the 16th consecutive year with below-average temperatures (an anomaly of -0.62°C/-1.12°F), the second coolest year behind 1996 which had an anomaly of -0.64°C/-1.15°F. The below-average stratospheric temperatures are consistent with the depletion of ozone in the lower stratosphere and the effects of increasing greenhouse gas concentrations. The large temperature increase in 1982 is attributed to the volcanic eruption of El Chichon, and the increase in 1991 was associated with the eruption of Mt. Pinatubo in the Philippines." http://www.ncdc.noaa.gov/sotc/index.php?report=global&year=2008&month=ann In my understanding of the above, NOAA is saying that volcanic activity INCREASES WARMING, so if there was increased volcanic activity during the Little Ice Age, according to them it would have counteracted the cooling during that period...
123562. tobyjoyce at 19:24 PM on 23 February 2010
        Have American Thinker disproven global warming?
        @garythompson, Your claim is: "A key component of the scientific argument for anthropogenic global warming (AGW) has been disproven." Even if this was true, it does not disprove AGW in toto, contrary to your commenters at American Thinker. Many theories, accepted as valid, are often retained even with an anomaly or two. Newton's Law of Gravity could predict the existence of Neptune, but was not rejected solely because it could not explain the orbit of Mercury (Einstein's theory could). Science works in "paradigms", or (perhaps better) in "research programmes", of which climatology has been a resounding recent success. As we know through the work of Naomi Oreskes, 95% of climatology papers accept AGW. So to bring your claim home, you need to get it peer-reviewed & published, discussed at conferences and tested with new data. Science is inherently conservative and an accepted paradigm is not changed easily. Having read your article, I find like Ricardo at #34, your failure to discuss the last chart in paper 3 rather damns your thesis. You take the previous two charts, claim that one can be overlaid on the other, there there is no difference in the OLR between 1970 & 1997. But chart 3 shows is difference is non-zero. It seems to me that you lack the analytical skills to seriously investigate these data, because "eyeballing" is just not good enough.
123563. Cowboy at 18:15 PM on 23 February 2010
        What would happen if the sun fell to Maunder Minimum levels?
        But isn't the theory of "greenhouse gases" that solar energy is absorbed by gases in the atmosphere? Is particulate matter in the atmosphere generally not as reflective as the globe, or is it somehow less capable of energy transference? Doesn't global climate envelope all ocean currents, regardless of their paths and speed? I mean, I can understand that a local condition (by Milankovitch forcing?) could cause a local change in atmospheric water vapor which could be spread and/or transferred to other locations. But wouldn't such events be "averaged" over just several decades, much less 70 years? After all, the quote I referenced said "possible changes" in ocean current patterns anyway. I don't claim to be any form of climatologist, but formal training as an engineer does teach one how to analyze scientific data. And I see things such as a desert in Arizona where there used to be a sea, and that change, along with similar changes, happened long before industrialization and man-generated CO2 (leaving aside the exhaling thing). What I get from your comment (no disrespect intended) and wording like "POSSIBLE changes in ocean current patterns" is that there are still far too many potentially related variables and unknowns to even think about trusting long-term climate modeling, particularly on a global scale. I am personally in favor of keeping an eye on the big picture history and events until there is actual evidence that models produce more accurate results. Particularly with recent events that have caused question with respect to the reliability of data used in who-knows-how-many models. Incidently, with an understanding (?) that Maunder is related (second cousins, I think) to "greenhouse gases" with respect to climate, I was looking for graphs I have seen that showed historic atmospheric CO2 level increases lagging global temperature increases. Do you know the current thinking with respect to that data?
123564. Tom Dayton at 17:32 PM on 23 February 2010
        What would happen if the sun fell to Maunder Minimum levels?
        Cowboy, the part of that quote that makes it consistent with this Skeptical Science post is "...in concert with increased volcanism and possible changes in ocean current patterns."
123565. Cowboy at 17:14 PM on 23 February 2010
        What would happen if the sun fell to Maunder Minimum levels?
        Is it not true that... "The longest minimum on record, the Maunder Minimum of 1645-1715, lasted an incredible 70 years. Sunspots were rarely observed and the solar cycle seemed to have broken down completely. The period of quiet coincided with the Little Ice Age, a series of extraordinarily bitter winters in Earth's northern hemisphere. Many researchers are convinced that low solar activity, acting in concert with increased volcanism and possible changes in ocean current patterns, played a role in that 17th century cooling." http://science.nasa.gov/headlines/y2008/11jul_solarcycleupdate.htm
123566. JDoddsGW at 16:55 PM on 23 February 2010
        Have American Thinker disproven global warming?
        This discrepancy between the GCM models and the Satellite measurements has been known and discussed for years. The results has always been inconclusive.There has been no way to reconcile the results. 1. If you believe in the GCMs then they are right. If you believe in Satellite measurements then they are right. The conclusion is NOT definitive. The two systems get different conclusions. There is no way to determine which is correct.(so far) To take it one step further, I take exception to both studies. They are both wrong. Now try a THIRD theory. Called "EXCESS CO2 Scenario "(available free at www.scribd.com.) First I take exception to Gary Thompsons assumption that the GHE is valid. Arrhenius's GHE IS valid. He said Add an energy photon to a GHG and you get GHE warming. IPCC & the GCMs GHE says : Add a GHG to the air and you get warming. (They implicitly assume that there is excess photons always available for every GHG that is added) This is wrong. It is my claim that Arrhenius's GHE only works up to the point where we reach equilibrium in the air. I.e. if there is excess energy photons, then adding a GHG will give more GHE. BUT when you get to equilibrium, where energy in equals energy out to space via direct radiation AND CO2 delay & then radiation (hence GHE warming) , then ALL of the absorbable energy photons DO get absorbed, and there are no more available for when you add more GHGs. If there are no more photons available then you have EXCESS GHGs in the air AND the GCM feedback mechanisms do NOT work because there are no more photons to be absorbed by the feedback WV GHGs. The simple proof is that the energy spectrum for both CO2 & Water Vapor absorbs 100%.i.e. leftover GHGs. The next proof is that there is excess WV in the air. Otherwise the GHE would continue (runaway GHE) until all the WV was at the 900C of a GHG with a photon.- i.e. the GHE would continue until the oceans dried up. Third proof: When the humidity of the GHG WV goes from say normal 33% to raining or 100%, then the temperature does NOT increase like it should (i.e. instead of 32C from WV we should get 96C from rain??? It doesn't happen. But if the energy photons are limited and limiting then when you add more WV then the GHE would not increase. 4th proof: In the morning the sun light energy photons increase. The GHE increases. At night the sunlight goes to zero, The temperature decreases, the GHE decreases. The CO2 and WV that WAS transporting photons to space as part of the GHE, no longer do it. so they are now made available in the air, i.e. the available GHGs increases, but the temp goes down as the GHGs goes up. IPCC is wrong. IT is the Photons that dictate, NOT the GHGs. Once you get to equilibrium, the Arrhenius GHE CHANGES to no longer work. (there are no energy photons to drive it.) This means that adding more CO2 by mankind burning hydrocarbons, ONLY adds more excess unused GHGs to the air (more plant food) Finally I PCC's "more GHGs means more GHE" is wrong (only works when excess energy is available) because you can NOT warm an object up without adding energy (2nd Law of Thermo) What this all means is that 1. Arrhenius's GHE works, but only up to equilibrium where it becomes limited by the amount of photons coming in. (i.e. about 32C out of 287 or about 11%). BUT when the energy in increases every morning and the temp goes up by say 10C, then 11% of that is due to INCREASED GHE. As is 11% of any reduction when the sun goes down. 2. We are at equilibrium daily- go from absorbing energy to radiating on a rotating basis. Hansen's GCMs claims that we are NOT at equilibrium for 50+ years due to the extra added CO2. This is wrong. As #29 was getting to, if the ground gets hotter then it radiates more faster until we cool off to equilibrium (as dictated by the amount of energy coming in). Likewise if we cool off (unless volcano dust reduces the energy in,) the energy in will keep pushing and pushing and pushing until the temp returns to the equilibrium dictated by the energy in. It happens every day, at the speed of radiating photons (i.e. speed of light) Bottom line Mankind can NOT change the temperature unless he changes the amount of energy coming in (volcano dust, SO2 will lower it), or produces more energy (by oil gas & uranium- which is super trivial compared to solar insolation.) All adding more CO2 does is add more excess CO2 to the air. i.e. AGW is false. BUT GW is true. (as the AGW experts claim- a few missing data points do not change the conclusion that we have warmed. BUT obviously it DID warm from 1970-1998. So what caused it (because solar insolation has essentially been constant since the 60s.??? See John Dodds Wobble Theory of Global Warming at www.scribd.com - summary is free!) (John Cook, on the basis of the referenced papers I request that you ADD Gravity and Planetary Eccentricity to the list of causes of Warming & climate change)
123567. Tom Dayton at 16:54 PM on 23 February 2010
        Have American Thinker disproven global warming?
        guinganbresil, your assertion that "...OLR increase resulting from this would have to be less than the decrease due to increasing CO2, otherwise the balance would be reversed and cooling would ensue" is incorrect because it is an overgeneralization. So is "The OLR will only increase after the GHG increase has stopped or slowed significantly." The amount of increase in OLR depends on the actual values in the specific situation, of the extra insulation from the greenhouse gases, of the rate of incoming radiation, and the rate of temperature increase. What you have stated as a logical requirement is not a logical requirement. It is only one possible case.
123568. Uncle Pete at 16:28 PM on 23 February 2010
        Have American Thinker disproven global warming?
        @coal geologist Not only are you a geologist, but you also make a great psychologist. I have been wondering for a long time why people simply cannot, or do not want to get their head around what is in essence a simple truth, namely AGW.
123569. guinganbresil at 16:10 PM on 23 February 2010
        Have American Thinker disproven global warming?
        I am glad to see some serious discussion on this issue! I agree that the IMG, IRIS and AIRS spectral data do not cover a sufficient band to see the whole picture. Non-spectrally resolved satellite measurements indicate that the total outgoing long wave radiation has gone UP over periods of increasing CO2 and temperature. Here is one example: http://www.isprs.org/publications/related/ISRSE/html/papers/332.pdf As CO2 concentrations increase, the total OLR should decrease since more and more of the long wave radiation is trapped that would otherwise have escaped to space. If OLR does not decrease, then the radiative balance would be moving toward cooling, not warming. The increase in temperature to move the system back toward equilibrium would result in more IR emission as temperature goes up, HOWEVER the OLR increase resulting from this would have to be less than the decrease due to increasing CO2, otherwise the balance would be reversed and cooling would ensue. I would understand a relatively constant OLR, since an increase in surface emission in the window region could balance the decrease in the CO2 band in a quasi-equilibrium condition of increasing CO2. An increasing OLR is just not supported by increasing GHG warming. Some have said that OLR is predicted to increase - see Murphy 2009, Figure 1. This is a fundamental misunderstanding. The figure in Murphy is for an idealized step function increase in GHG. The increasing OLR only occurs AFTER the increase in GHG has STOPPED. When you apply this step function response to a monotonically (long time scales of course) increasing GHG concentration, the OLR will DECREASE over time. The OLR will only increase after the GHG increase has stopped or slowed significantly.
123570. Deech56 at 13:17 PM on 23 February 2010
        Have American Thinker disproven global warming?
        It seems that a lot of those who comment on the site (American Thinker) have a poor understanding of how scientists get paid through grants. I would correct them, but, alas, I am forever banned. Glad to see others contribute to the comments pages this article at AT. Good article, John. Love the iPhone app.
        Response: Don't forget to post a review in iTunes :-)
123571. Ned at 12:19 PM on 23 February 2010
        Visual depictions of CO2 levels and CO2 emissions
        Theendisfar, both of your most recent comments here seem to include a hodgepodge of facts regardless of their relevancy. I would suggest that if you want to engage in a discussion, pick some particular point and try to present it as clearly as possible. The comparison of the Moon and the Earth is one example. You originally made the statement "Without an atmosphere to convect much of the energy away from the surface, the surface would be much hotter and radiate at a higher energy similar to the moon." I pointed out to you that in fact the surface of the Moon is colder than that of the Earth, when it should be warmer due to its lower albedo. The difference between the two is the direct result of the Earth's surface being warmed by greenhouse gases. This is not a controversial statement, and in fact has been understood since the 19th century. It's also not a "side note analogy," it's a basic piece of confirmatory evidence that the theory of radiative forcing from greenhouse gases is correct. I'm not really sure I understand the point you're trying to make about convection and latent heat. Ultimately, the only way the Earth system gains and loses heat is via radiation. The movement of heat within the climate system is important, and the details get a bit complicated, but they're not really necessary for a first-level discussion of the greenhouse effect. If your claim is that the greenhouse effect doesn't exist, you'll need to find someone else to debate that with -- I've just spent the past couple of days here engaging in that argument with another commenter, and I'm uninterested in spending any more of my life right now explaining what from my perspective is very well established, uncontroversial physics. Let's see, what else? You ask: Would you happen to have a link to an actual AGW Hypothesis or Theory? It is quite difficult to refute something that cannot be or has not been described accurately. Perhaps you can expand on your statement if one does not exist. There are many different kinds of scientific theories. If you want to get pedantic about it, the "theory of climate change resulting from anthropogenic emission of greenhouse gases" is very analogous to the "theory of plate tectonics". Both of them developed over a period of time through the contributions of many scientists working in different fields. Neither one can be readily reduced to equations or simple laws, and neither one has a central manuscript along the lines of Einstein's or Newton's papers. Neither one can be completely tested in the lab, though portions of each can be. Ultimately, both theories gained acceptance from the scientific community by combining a convincing theoretical framework with multiple independent lines of empirical evidence. Requests for "a link to the theory of the greenhouse effect" are as much of a red herring as requests for "a link to the theory of plate tectonics". In both cases, if you are genuinely unclear on what the theory involves, you would be better suited to audit some Earth Sciences courses at your local university and/or work through a good, appropriate textbook.
123572. CoalGeologist at 12:15 PM on 23 February 2010
        Have American Thinker disproven global warming?
        John Cook interprets Gary Thompson's misreading of the scientific literature as evidence of the Dunning-Kruger effect, but I feel this is a misinterpretation of D-K, and also misses the role of an even more harmful influence in the interpretation of scientific data, which is bias. D&K provide evidence that individuals having a low level of understanding of a topic tend to overestimate their own degree of mastery of that topic; however D&K treat this phenomenon as distinct from bias. While Thompson’s self-assessment might be higher than it should be (or not?), it would be difficult to argue that his knowledge of radiative heat transfer is not substantially greater than average. Why should this knowledge not provide an advantage, rather than a disadvantage, in his reading of the literature? The culprit here appears to me to be the insidious impact of bias. In contrast with pharmaceutical evaluations, or other experiments where human psychology can influence the results, we cannot realistically design a “double-blind” experiment to remove the influence of bias in the study and interpretation of climate change. We are constrained, instead, to making a sincere effort to minimize its impact. Skepticism is fine; however, if we approach climate science with the presumption that AGW is wrong, and that, ipso facto, evidence that appears to support it must be wrong as well, we substantially increase our chances of misinterpreting the scientific evidence by unjustifiably dismissing or ignoring evidence that is inconsistent with our ideology, and by failing to apply the same level of skepticism toward our own reasoning that we apply to evidence supporting AGW. After reading the articles, and blog comments above (including Mr. Thompson’s @#28), I conclude that Mr. Thompson has commited both offenses in the present case, perhaps inadvertently. Simply acknowledging the risk of bias is less than half the battle of eliminating its effects. I have seen many well intended individuals completely undone by bias, of which they seem to have only the faintest glimmering of self-awareness. Given the preponderance of specious arguments in the climate change “debate”, and the pervasive political ideology in AGW skepticism, it’s my conclusion that most of the criticism of AGW is rooted in ideology rather than science, and efforts to build a scientific case typically lead to what we see here. Indicators of the (inferred) ideological roots of Mr. Thompson's position may be found in his “Straw Man” definition of AGW (cf. Post #28 and #33), the politically “loaded” rhetoric in his essay, as well as the political slant of the very webzine where he chose to publish his results. (And while I’m not convinced that Mr. Thompson’s essay itself provides evidence for the Dunning-Kruger Effect, it’s worth considering that the webzine title “The American Thinker” might!) To me, this is the principal battleground of the present climate change debate, while climate scientists continue to do their best to understand the scientific evidence.
123573. joseph449008 at 11:04 AM on 23 February 2010
        Have American Thinker disproven global warming?
        

        Please correct me if I'm talking nonsense here... I'm just trying to learn.

        I think that's largely correct, Marcel. The irradiance from the Sun also can change, however, as can the bond albedo of Earth. These are relatively minor changes, though.
123574. Riccardo at 10:54 AM on 23 February 2010
        Have American Thinker disproven global warming?
        garythompson, i have a couple of comments on your article and, of course, on the explanation given here. The first is not about the science. You accuse the authors of the three papers of substituting actual measurements with model data while you omitted to show the third graph in Chen et al where both model results and data are shown. This a serious omission which undermine your claim. As for the sicence, there is a clear misinterpretation of how the radiative balance works. Indeed, it is not true that one should expect an overall decrease in OLR. If the planet is out of balance, as it is now, and trying to recover it needs to increase the overall OLR by increassing its temperature. This simple concept is unfortunately too often overlooked. What we see in the IR spectra is the superimposition of these two different effects, a decrease of the IR intensity at the absorption bands due to the increased GHG concentration and an increase elsewhere (the background thermal radiation from the surface) due to the increasing surface temperature. No surprise that near the edges of the absorption band the increasing thermal emission may outweight the increased CO2 absorption. On passing, extending the measurement range to lower wavenumber would not add much. Below 700 cm-1 the absorption saturates and the difference would obviously go to zero; you will end up with two spurious peaks on the two sides of the central frequency with zero in between.
123575. dorlomin at 10:31 AM on 23 February 2010
        What would happen if the sun fell to Maunder Minimum levels?
        In terms of the little ice age, would Milankovitch forcing have played a major role in why it got cold? I have always thought that we should be entering a stadial like conditions at this point of the Holocene.
123576. theendisfar at 10:18 AM on 23 February 2010
        Visual depictions of CO2 levels and CO2 emissions
        Ned, You took the analogy too far and out of context. The Earth and Moon are not compatible with regards to truly making the analogy. My intent was to show that Convection spreads out the energy that would otherwise be trapped all at the surface. Perhaps it was unclear? The Moon's surface area is smaller meaning it gets less solar irradiance, and rotates every ~29 days meaning it gets 14 days of sunlight and then 14 days of night. Lastly, the Earth does indeed have an atmosphere, 5,000 Trillion tons of it, 99% N2 and O2. Do you take an opposition to any of the substance of what I wrote, or were you just looking for something to quip? Fortunately for us, CO2, CH4, water vapor, etc. do in fact warm the planet. Otherwise, Earth would be a ball of ice. Not trying to be a denialist :), but none of the above 'warm' the planet. They simply slow the cooling rate. By how much? CO2 'traps' 2 W/m^2. This is a tiny amount of energy as compared to what Convection and Evaporation transfer from the surface to the Tropopause. See above. Would you happen to have a link to an actual AGW Hypothesis or Theory? It is quite difficult to refute something that cannot be or has not been described accurately. Perhaps you can expand on your statement if one does not exist. Given that Convection and Evaporation exist, how does the GHE slow the cooling of the planet without slowing the Convection or Evaporation rates? The GHE is a terrible misnomer. Whatever gets trapped, will simply use convection or evaporation as there is nothing impeding them. Perhaps you take issue with this statement? Being new here I should expect some misunderstanding and jabs. Please note, I am a lover of nature, I hike, I camp, and I ALWAYS carry out more trash than I take in. With regards to AGW, it is the scientific method that led me to become a skeptic, not politics. If you think getting clever with me improves your position here, by all means continue, but at least attack the substance rather than picking apart side note analogies. With that, no harm no foul. Have a good one, looking forward to your rebuttal. The End is Far
123577. AndrewY at 09:52 AM on 23 February 2010
        What would happen if the sun fell to Maunder Minimum levels?
        CBDunkerson, thanks for pointing that out, I had missed the timing of the volcanic eruption event shown in Figure 3 (I should have guessed given that the temperature dip is such a sharp/strong feature). That's actually a relief, it means that in reality the dip in temperature is unlikely to happen at just that time (as I said, I had imagined it may have been due to some more predictable natural climate cycle, it would have been terrible timing). Strangely, I find myself happy at the news it is shaping up to be a really hot year (and that's not just because I live in the UK :o)
123578. Steve L at 09:44 AM on 23 February 2010
        Have American Thinker disproven global warming?
        garythompson @ 28 quotes himself for the AGW hypothesis: "increased emission of CO2 into the atmosphere (by humans) is causing the Earth to warm at such a rate that it threatens our survival." My question isn't a technical one: where did this definition of 'the AGW hypothesis' come from? It doesn't seem like a very scientifically-stated hypothesis. Is it anything more than a strawman?
123579. carrot eater at 09:38 AM on 23 February 2010
        Is CO2 a pollutant?
        yeah. a lot of G&T is just irrelevant. I'm inclined to guess that nobody really reviewed it; it's not just bad, but it's full of inappropriate language.
123580. KR at 09:36 AM on 23 February 2010
        Is CO2 a pollutant?
        I've just been reading the G&T paper. Oh, my. To quote Wolfgang Pauli "This isn't right. This isn't even wrong."
123581. Pierre-Normand at 09:18 AM on 23 February 2010
        Have American Thinker disproven global warming?
        The "clack" line is black, of course.
123582. Pierre-Normand at 09:11 AM on 23 February 2010
        Have American Thinker disproven global warming?
        Gary Thompson, In your AT piece you said: "All three of the links referenced here devote the latter sections of the papers to removing the impact of surface temperatures and water vapor and graphing the OLR that is associated only with trace GHGs. The authors perform this trick (there is that word again...) based on the climate models and not through actual measurements, and surprise, surprise -- these simulated results show a reduction in OLR emission with wavelengths that are absorbed by CO2. Computer-simulated results based on climate models are never a replacement for actual measured data [...]" But the authors cited compare the increase in absorption to the increase the models predicted would occur at those wavelengts. So, the model differential outputs get compared to the subtration of the two observed spectra. Look at figure 3 in Chen et al.. The clack line on this graph is the result of directly subtracting IRIS data from TES data. Yet, in the your AT piece you only displayed the first two figures and suggested IRIS and TES were identical. Figure 3 shows that they aren't regardless of the model predictions.
123583. Philippe Chantreau at 09:10 AM on 23 February 2010
        Have American Thinker disproven global warming?
        Gary Thompson says here: "I tried to be very clear in the article that the authors came to very different conclusions than I did and the authors were very clear as to why they came to those conclusions." In the comment thread of your blog, he says this: (Posted by: gdthomp01 Feb 18, 03:07 PM) "But even on the wavelengths shown, there was no decrease in OLR at those wavelengths so I still felt comfortable drawing the conclusions I did - and the authors of these papers (using simulated results from climate models) drew those same conclusions using these wavelengths although they weren't based on the actual measurements." This is hard to reconcile with the conclusion of the Chen article that I quoted above and clearly addresses the measurements: " Changing spectral signatures in CH4, CO2, and H2O are observed, with the difference signal in the CO2 matching well between observations and modelled spectra." In addition to the measurements, it would be strange for them not to examine model results, since these were the very subject of the paper. They found the model results to correspond very well to the observations, contrarily to what G. Thompson suggests in his conclusion. Thompson's conclusion also misrepresents the intention of the autors by alluding to possible dishonest conduct, or attempts to "trick" the reader, a reference to the well publicized hacked e-mails. G. Thompson: "All three of the links referenced here devote the latter sections of the papers to removing the impact of surface temperatures and water vapor and graphing the OLR that is associated only with trace GHGs. The authors perform this trick (there is that word again...) based on the climate models and not through actual measurements, and surprise, surprise -- these simulated results show a reduction in OLR emission with wavelengths that are absorbed by CO2." This in complete disagreement with Chen's conclusion (see above), since they clearly address the observations.
123584. Marcel Bökstedt at 09:04 AM on 23 February 2010
        Have American Thinker disproven global warming?
        I find this very interesting. From my admittedly low level of understanding, it seems that the main point is the following. Let us for the sake of the argument ignore all the complications of climate, and only discuss the effect of greenhouse gasses. This is a very crude simplification, but lets make it anyhow. Then a certain concentration of greenhouse gasses will correspond to a certain ground equilibrium temperature. At this temperature, the Earth will radiate exactly as much heat as it absorbs from the sun. If the actual temperature on the ground is lower than the equilibrium temperature, the ground will warm up. As it warm up, the Earth radiates more heat, and eventually equilibrium will be restored. So we do not expect to see a net influx of heat at any particular time, we expect (in the first approximation) an approximate balance between the more or less constant influx from the sun and the total heat radiation from Earth into space. What will change if we increase the amount of greenhouse gasses is not the total amount of radiation over all wavelengths (that will be approximately equal to total influx, and thus constant), but the distribution of the radiation over wavelengths. If the heat radiation from the Earth increases at some wavelengths it must also decrease at some other wavelengths, because in the first approximation we expect the total amount to be roughly constant. Since we know that the Earth has has warmed in the period 1970-1996, we would naively expect an increase in the total amount of heat radiated from the Earth. This cannot be, and has to be explained somehow. The AGW hypothesis explains this is saying that some of the radiated heat is trapped, shifting the escaping radiation down at some wavelengths. I believe that it does not say that the total amount of escaping heat has changed - just its distribution along the spectrum. Please correct me if I'm talking nonsense here... I'm just trying to learn.
123585. garythompson at 08:22 AM on 23 February 2010
        Have American Thinker disproven global warming?
        I am the author of the AT piece. First off let me tell the website admin (John Cook) that I really like this website. This and Realclimate.org are the two main sources I go (daily) to see the science debated and talked about. as I stated in the article, I’d rather debate the science than talk about the IPCC, Climategate, Jones, Mann, etc. All of that makes good news stories but it doesn't get to the heart of this issue which is the science. And the fact that I frequent these sites and join in the discussions means I’m comfortable with criticism and having an open conversation about the science. I appreciate the comments/questions already posted and let me see if I can answer those who have asked something specific of the author (me). First off, I never stated in the article that I was disproving the greenhouse effect. My aim was to disprove the AGW hypothesis as I stated in the article "increased emission of CO2 into the atmosphere (by humans) is causing the Earth to warm at such a rate that it threatens our survival." I think I made it clear in the article that the greenhouse effect is not only real but vital for our planet (since we'd be much cooler than we are now if it didn't exist). Also, my aim was NOT to misrepresent the conclusions of the authors of the original 3 papers. I tried to be very clear in the article that the authors came to very different conclusions than I did and the authors were very clear as to why they came to those conclusions. There were three links to papers in this article and John chose to talk about one of them here (which happened to be the 2nd link) so I’ll take that one first. It is true that there is a spike down of about -1K in the region of 700-710 waves/cm but the rest of the range which extends to about 780 waves/cm, shows a the delta either zero or positive. The CO2 absorption range that is covered in the paper - as John pointed out and many know - extends further to the left and peaks at around 667 waves/cm so we don’t know what the data showed below 700 wave/cm. But if someone were to take this data - as given - and convert the BT measurements to OLR flux numbers (W/m2) I believe we'd see an increase in OLR flux (1997 vs. 1970) since the delta over the majority of this range (again, not the complete range but the range in this paper) will contribute positively to that delta. I didn't go through this exercise and plug this into the Planck function, integrate between the absorption wavelengths as listed in the paper and then compare the 1970 with 1997. I don't have the real data and to try and grasp that from a graph would be silly. Visually, this apparent lack of decline of OLR seems pretty obvious to me (when looking at the actual measured data). I suggest you take a look at the first link in the article as well. When looking at the graphs of the actual measured data in this paper, it becomes even clearer that there is an increase in OLR from 1970 to 1997 in the range where CO2 absorbs IR. The third link is the more updated Harries paper that several have posted about here so I did include that in the article as well (this compared OLR 2006 vs. 1970). In my opinion, this data falls into the same category as the paper reviewed here by John - a small -1K spike in the lower frequency OLR (again, it's not really the 'lower' frequency since the graph starts well to the right of the peak absorption for CO2) but then back up above zero for the higher frequencies in the CO2 absorption zone (which is also nicely grayed out in the more recent Harries paper). My point in this article was to show that you can see from the actual measured data that OLR is not decreasing in the area where we'd expect it to because of all the extra CO2 we've been spewing into the atmosphere (and just for the record, I am not arguing this CO2 rise - the Mauna loa data is easy to interpret). I was also pointing out the question that puzzled me - why the authors put so much value in the graphs that they produced via models - which showed a very large, significant drop in OLR in the CO2 range. We have increased the CO2 in the atmosphere about 17% from 1970 to 2006 (328ppm vs. 383ppm) and the OLR appears to have remained constant when you look at the raw data from these three papers. Does that mean water vapor is generating OLR that doesn't get absorbed by CO2? As John alluded to in his Q/A with Harries - I’d really like to see this data extended out to the 600 waves/cm to see what happens at the peak absorption wavelength of CO2. I’m fairly swamped at work this week and will check back if there are more direct questions you want to ask me. I only mention this so that no one takes my non-response as non-interest. If you have questions regarding details of this article I’ll try and respond as timely as I can. If there are no questions I’ll just sit back and enjoy the conversation and criticism. ok, let me have it.....
        Response: Gary, many thanks for commenting. You're correct in that your article wasn't about 'disproving the greenhouse effect' - I've updated that wording to 'disproving the enhanced greenhouse effect' which I believe more accurately represents your position.
        
        I'm not sure that the authors do put so much value in the simulated graph (eg - Figure 1c from Harries 2001). The main point of their papers is to compare the measured data with the simulation (Figure 1b) to show that our understanding of the enhanced greenhouse effect is confirmed by observations. The use of modelling to filter out the effects of humidity in order to show the isolated effect of trace gases is not a crucial part of the paper (but it is interesting).
        
        I'm not optimistic that we'll see the analysis extended to 600 cm^-1 as that is limited by the 1970s satellite data.
        
        Anyway, I appreciate your comments and expect (nay demand) that commenters here will abide by our commenting policy and treat you with respect.
123586. joseph449008 at 08:16 AM on 23 February 2010
        Have American Thinker disproven global warming?
        The drop on the left is probably CO2. The drop on the right is either Methane or water vapor. The drop in the middle, I'm not sure. It could be CO2 as well. It could be Ozone. (I have a subscription to spectralcalc.com this month - still hasn't run out.)
123587. carrot eater at 08:02 AM on 23 February 2010
        Is CO2 a pollutant?
        Ugh. All that effort, for no resolution? Just note the inconsistencies in your own statements. First the problem was of magnitude, not principle. Then, you changed and there was a Second Law problem. But you couldn't find anyplace where net heat transfer went in the wrong direction. You must realise that G&T's argument won't allow for the 25 C wall to radiate towards the 50 C wall. This is simple stuff, which is why the scientific community can just dismiss G&T out-of-hand. It's just that wrong.
123588. Philippe Chantreau at 07:52 AM on 23 February 2010
        Have American Thinker disproven global warming?
        What Thompson does with the Chen 2007 paper is take the IRIS measured data graph (1970) and compare it to the TES measured data graph (2006), for brightness temperature. It's rather strange that he would do that, since there is a graph in the Chen paper that does exactly that and also compares the modeled results, it follows right after the other 2 graphs, the ones showed by Thompson. Then comes Chen's conclusion: "The TES data compare very well with the IRIS data, suggesting successful normalization of the different instrument characteristics. The TES and IRIS difference spectrum covers the time range of 1970 – 2006, a period of 36 years. Simulated spectra represent the state of the HadGEM1 coupled model for 1970 and 2006. Changing spectral signatures in CH4, CO2, and H2O are observed, with the difference signal in the CO2 matching well between observations and modelled spectra. The methane signal is deeper for the observed difference spectrum than the modelled difference spectrum, but this is likely due to incorrect methane concentrations or temperature profiles from 1970. In the future, we plan to extend the analysis to more spatial and temporal regions, other models, and to cloudy cases." Thompson makes no mention of that conclusion at all and does not delve into the details of how exactly he "suuperimposes" the TES and IRIS brightness temp curves, nor what would be the expectations considering how GH gases have varied over the 36 years.
123589. Ned at 07:47 AM on 23 February 2010
        Visual depictions of CO2 levels and CO2 emissions
        Without an atmosphere to convect much of the energy away from the surface, the surface would be much hotter and radiate at a higher energy similar to the moon. There's only one problem with this elegant hypothesis: the mean surface temperature of the Moon is colder than the Earth (around -20 C). In fact, since the Moon has a lower albedo than the Earth, in the absence of warming by greenhouse gases, the Earth would actually be even colder than that. Fortunately for us, CO2, CH4, water vapor, etc. do in fact warm the planet. Otherwise, Earth would be a ball of ice. This has been coming up a lot lately, for some reason. I just recently corrected someone else who was making the same mistake here.
123590. Philippe Chantreau at 07:29 AM on 23 February 2010
        Have American Thinker disproven global warming?
        Ubique, the "article" discussed does not really address any issue of magnitude. It confuses the readers by misinterpreting graphs picked from a peer-reviewed publication and suggesting conclusions based on the misintepretation. In doing so it completely fails to consider the very paper in which the graphs were found. I don't see how it could be of any interest whatsoever.
123591. suibhne at 06:29 AM on 23 February 2010
        Is CO2 a pollutant?
        carrot eater KR CBDunkerson Philippe Chantreau I think we are starting to repeat ourselves here. There is no point in restating positions endlessly. As I have stated, a peer reviewed article maybe passed for publication going over the same ground as G&T and will no doubt be commented on. Thank you for an interesting discussion. This forum provides a space where rational discussion can take place. This is a topic where irrational emotion based mud slinging is all to common and does neither side of the debate any good.
123592. Doug Bostrom at 06:10 AM on 23 February 2010
        Have American Thinker disproven global warming?
        Ubique at 04:05 AM on 23 February, 2010 In order to "seriously challenge" the AGW hypothesis, Thompson's paper would need to be free of the errors John identified, misinterpretations that leave Thompson's argument seriously deficient. Can you refute John's analysis?
123593. Riccardo at 06:00 AM on 23 February 2010
        Have American Thinker disproven global warming?
        RSVP, the continuos part of the spectrum comes directly from the surface and reflects surface temperature. The atmosphere is overall much colder, i.e. much lower emission intensity and a peak shifted to lower wavenumbers, and being almost transparent has a lower emissivity. On the contrary, the level at which the strong absorption bands saturates reflects the tropospheric temperature or, to be more precise, the air temperature at the height from which IR escape directly to outer space.
123594. theendisfar at 05:54 AM on 23 February 2010
        Visual depictions of CO2 levels and CO2 emissions
        Chris G, Whether the cooling/heating (transfer of energy) is radiative, convective, or done by evaporation, it is a transfer of energy no less, no energy ceases to exist or is created. Evaporation does not remove energy from the Earth's thermo system, however it does transfer ~30 Sextillion (1 Million Trillion) joules (~2300 Joules/gram) away from the surface to the upper Troposphere every ~10 days, Radiation takes over from there. Recall that the Earth's average Surface temp is 14 C and it is reduced to -56 C as convection takes place (PV=nRT) up to the Stratosphere. Radiation transfers energy at 300,000,000 meters per sec (speed of light (c)) while convection does it on a much slower, albeit larger, scale ranging from less than 1 m/s to less than 100 m/s. Radiation is very quick, but lacks force, convection is very slow but has lots of force. If you look at this from a standpoint of Work it becomes clear that convection does far more work than Radiation within a convective zone. http://hyperphysics.phy-astr.gsu.edu/hbase/HFrame.html Any IR "trapped" is literally trapped at the surface. If the IR is trapped at 1 meter, it is at the surface 150 Million times per second, very much like never leaving the surface, at 10,000 meters, altitude of the Tropopause (end of convective zone), it is reduced to 15,000 times, but still very much like never leaving the surface. The IR that escapes directly to space, which is most of it, nearly reaches the orbit of the moon over the same period. Knowing that a cubic meter of water at 14 C contains about 1.2 Billion joules, trapping 2 joules/sec amongst the 1.2 Billion will not raise the temp given that it takes around 4.1 Million joules to raise it 1 C. Given the Earth experiences 12 hours of night as well, this bodes poorly for the AGW Theory. (BTW - Is there an actual AGW Theory? Not being crass, just have never seen it described as a Theory like Evolution or Relativity) Lastly, you are correct, not to the exclusion, but given two paths, it will take the path of least resistance up to the point where the most efficient is saturated (this happens within millionths of sec over and over again) so Convection and Radiation do occur at the same time within the Troposphere, just more energy is being transfered via Convection. So while CO2 may trap 2 Watts (joule/sec) amongst the billions via radiation, entropy dictates that it will simply use convection or evaporation as a more efficient means to escape instead. There are many paths to the Tropopause and only one outside of that. Without an atmosphere to convect much of the energy away from the surface, the surface would be much hotter and radiate at a higher energy similar to the moon. A convective zone essentially spreads the energy, that would otherwise all be trapped at the surface (2D), over a larger volume (3D). Increasing volume reduces pressure and temperature.
123595. Riccardo at 05:47 AM on 23 February 2010
        Visual depictions of CO2 levels and CO2 emissions
        Chris G, I may be wrong but as far as i can remember the first to account for humidity and radiative-convective equilibrium was Manabe et al. 1967.
123596. 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.
123597. 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.
123598. 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.
123599. 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."
123600. 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.

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