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Comments 82751 to 82800:

82751. dana1981 at 06:00 AM on 15 June 2011
       Climate change is real: an open letter from the scientific community
       This is an excellent letter - harsh, but true. I like how they didn't pull any punches. The whole series should be interesting.
82752. les at 06:00 AM on 15 June 2011
       The greenhouse effect is real: here's why
       22 - paddy; leaving science to one side and concentrating on English comprehension, may I draw your attention to the top of the page "Reposted from The Conversation." This is not a SkS science article I'm not going to paraphrase your "need to do better" words as that would just be obvious and tacky.
82753. John Hartz at 05:56 AM on 15 June 2011
       The Planetary Greenhouse Engine Revisited
       My one-line repsonse to climate denial bloggers who post about the Venusian atmosphere: "What happens on Venus, stays on Venus!"
82754. Albatross at 05:43 AM on 15 June 2011
       The greenhouse effect is real: here's why
       Patrick @22, Your weeping dismissal of the alleged absence of science are quite ironic given that your post contains no science whatsoever, never mind any attempt to substantiate your position. Indeed, you need to do much better on a science site.
82755. John Hartz at 05:29 AM on 15 June 2011
       The Planetary Greenhouse Engine Revisited
       Kudos on an excellent post.
82756. Patrick Kelly at 05:17 AM on 15 June 2011
       The greenhouse effect is real: here's why
       I must say that I find this article to be a very disappointing addition to a site that headlines itself as Science based. Long on assertion and ambitious in conclusions which stem from very little solid scientific argument. Need to do better.
82757. angliss at 04:59 AM on 15 June 2011
       The Planetary Greenhouse Engine Revisited
       Thanks!
82758. Chris Colose at 04:56 AM on 15 June 2011
       The Planetary Greenhouse Engine Revisited
       I hadn't seen this before but I just added it to the Recommended reading
82759. Albatross at 04:52 AM on 15 June 2011
       Forecast: Permanently Hotter Summers in 20-60 years
       Hi Chris, Re your #25. Sorry if I was not clear-- my dig was at Eric, not you-- I very much appreciate you clarifying the Keenlyside et al. issue :) I concur with you that the Earth will be quite a bit warmer by 2030.
82760. angliss at 04:51 AM on 15 June 2011
       The Planetary Greenhouse Engine Revisited
       Hopefully no-one's offended by this self-promotion, but I did a five-day series of posts that took apart common denier arguments for how Venus could be kept hot by means other than the greenhouse effect. This link goes to the first of the series.
82761. Bob Lacatena at 04:27 AM on 15 June 2011
       The greenhouse effect is real: here's why
       I'd like to point out another minor inconsistency in the fingerprints. The idea that winters and nights will warm more than summers and days, while true, should also apply to a lesser degree to any forcing, since many of the primary feedbacks are themselves greenhouse gases (mostly H₂O). At the same time, part of the overall feedbacks for even an initial GHG forcing include changes in albedo, which would not bear the same signature. So while a pure GHG increase from CO₂ now will involve a larger degree of difference, it could be difficult to tease out the difference between, say, a pure CO₂ forcing versus a pure solar forcing. Both will have non-winter/daytime components and winter/nighttime components, to different degrees. I've tried to find someone knowledgeable about various climate model runs, to figure out exactly what the difference might be, but so far with no luck, so I can't quantify this in any way. All I can say for certain is that any warming will have both a GHG component and an albedo component as part of the positive feedbacks, and as such the difference between an initial GHG forcing and another forcing may not be as pronounced as one might initially expect, or would want (to be able to discriminate, observationally, between the two forcings).
82762. chris at 04:17 AM on 15 June 2011
       Forecast: Permanently Hotter Summers in 20-60 years
       Albatross at 03:15 AM on 15 June, 2011 Yes fair enough Albatross. There are two relevant points though: 1) Eric was citing Latif as an indication of "cooling" in the next 20 years. So it's worth pointing out that Latif doesn't predict that at all. He predicts a large warming by the decade centered around 1930. 2) There is uncertainty about the extent to which "natural variability" is suppressing current warming a little. The evidence (including Latif's) suggests that ocean circulation variabilty might be suppressing surface temperatures a tad. We know that the extended solar minimum will also be countering greenhouse warming a little (we expect the drop of solar output from the max to min of the solar cycle to pretty much counter greenhouse-induced warming, although natural variability masks this somewhat). The point is that despite any current short term slowdown in warming, Latif (and pretty much all physics-based projections) indicate that the Earth will be quite a bit warmer by 1930. That's relevant to the subject of this thread.
82763. Dikran Marsupial at 03:52 AM on 15 June 2011
       Phil Jones - Warming Since 1995 is now Statistically Significant
       John Russell You are missing the point. There is no way to give an honest answer to that question that gives no room for misinterpretation by a dishonest adversary, and I rather doubt Prof. Jones was in a position to refuse the interview (given the circumstances). If you think such an answer exists, lets hear it.
82764. Chris G at 03:38 AM on 15 June 2011
       The greenhouse effect is real: here's why
       CB, FWIW, my presumption on the greater increase over land than water is that it is primarily related to the heat sink/energy transport attributes of land versus ocean. There are thermoclines, but oceans mix more rapidly than dirt; therefore, any energy delta at the surface is distributed over a greater volume over the ocean than over land. Not only does the energy get transported to depth, but also across meridians. I would expect this to have a sort of buffering effect, though thermal inertia might be a better concept to invoke semantically. On clouds, I agree, but, of course, some mechanism would have to drive the change in cloud behavior. Aerosols might do it since more of them would tend to lower the occurrence of supersaturated states. But then there are complications in the tradeoff between water vapor content versus droplet content, and whether they are high clouds or low clouds. For that matter, GCRs _might_ have an influence, but that would require evidence that has so far been lacking, or at least had big gaps, to the best of my knowledge. My two cents.
82765. Chris Colose at 03:33 AM on 15 June 2011
       The greenhouse effect is real: here's why
       Tom Curtis, My only point was that polar amplification is a rather common occurrence in climate change scenarios, regardless of whether we are talking about deep-time greenhouse climates, Milankovitch (orbital) timescale changes, or modern global warming, and has been simulated for a variety of forcings as well as "aquaplanet only" or other flavors of idealized experiments. Moreover, feedbacks associated with atmospheric dynamics and heat transport (and are not directly dependent on snow or ice) can contribute to polar amplification (e.g., Pierrehumbert 2002, Alexeev 2003; Alexeev et al. 2005; Cai, 2005). The other thing is that there are still recognized problems in simulating the pole-to-equator temperature gradient that proxy indicators report in some early greenhouse climates, so it is not clear to me that we have a convincing and full-proof quantitative theory linking the behavior of the pole-to-equator temperature gradient (and the meridional heat transport carried by the atmosphere and ocean) to the mean climate, so there's still work to be done here.
82766. Tom Curtis at 03:20 AM on 15 June 2011
       The greenhouse effect is real: here's why
       CBDunkerson @17, the ocean warms slower because it has a greater heat capacity than the land. Consequently it takes more heat for each degree centigrade increase in temperature. Of course, that has no influence on the equilibrium temperature, so once the TOA energy balance reaches equilibrium again, the ocean and land will have warmed equally. Increased cloud cover will indeed warm the nights more than the days, but will only provide an overall warming if clouds are a positive feedback. Of course, increased cloud cover will also tend to warm the stratosphere rather than cool it (although probably not very much). Reduced aerosols will warm the troposphere and cool the stratosphere, but will also increase the diurnal temperature range, and the temperatures of summer relative to winter. If clouds are a negative feedback, reducing clouds will show the same pattern.
82767. Albatross at 03:15 AM on 15 June 2011
       Forecast: Permanently Hotter Summers in 20-60 years
       Chris @23, To add to you post. Last November RealClimate had a look at how Keenlyside et al's forecast panned out...the short story is that is has not. [Source] I really would like to put the whole Mojib Latif debacle that has been doing the rounds for a couple of years now to rest (thanks to the efforts of some misguided journalists and the denialist spin machine, including Lindzen), and it is annoying to see that to this day 'skeptics' are still touting it, even in the face of reality. Anyhow, I am not sure why we are focussing on this when the post is about future warming and preponderance of extreme heat.
82768. michael sweet at 02:57 AM on 15 June 2011
       Websites for Watching the Arctic Sea Ice Melt
       DB: that would be nice. Sphaerica's illustration is better than mine.
       Response:

       [DB] Done.

82769. chris at 02:54 AM on 15 June 2011
       Forecast: Permanently Hotter Summers in 20-60 years
       Eric the Red at 23:50 PM on 14 June, 2011

       "Much of the focus related to "cooling" in the next 20 years comes from presentations like Latif and Easterbrook with regards to the multidecadal oscillation."

       Eric, Latif certainly doesn't think the Earth is going to "cool" in the next 20 years. His simulations, taking account of ocean circulation changs that (he thinks) will put a slight break on warming for a decade or so (2005-2015ish), indicates a rather rapid subsequent warming such that by 2030 he consiers we'll be a further 0.4-0.5 oC (globally averaged) warmer. see e.g. Figure 4 of Latif's recent paper on global warming forecast here.
82770. CBDunkerson at 02:50 AM on 15 June 2011
       The greenhouse effect is real: here's why
       Tom, thanks for the information on the direct component of polar warming from greenhouse gas accumulation. The bit about 'fingerprints' only being unique to greenhouse warming in toto rather than each individually is also new to me. I've been trying to think of another forcing which would cause accelerated night-time warming. Increased cloudiness might work... more clouds during the day = increased albedo and thus cooling / more clouds at night = less heat escaping and thus warming. Also, do you know what the physical mechanism for atmospheric warming being greater over land than the oceans is? Is it just net heat flow? That is, the ocean water absorbing more heat from the air than it expels TO the air?
82771. chris at 02:42 AM on 15 June 2011
       Forecast: Permanently Hotter Summers in 20-60 years
       Tom Curtis at 02:15 AM on 15 June, 2011 You may know of this paper which supports the interpretation that under conditions with a solar constant not that different to the present, that the thresholds for Antarctic glaciation is around 750 ppm and for Greenland is of the order of 280 ppm. Since these values correspond to thresholds for the onset of the respective polar icesheets, there is presumably signficant hysteresis for the loss of polar ice under warming conditions (due to offsetting albedo effects). However I think the evidence supports the conclusion that we are already near the CO2 threshold where the Greenland ice sheet is committed to disappear. Haven't looked at data that bears further on this from last couple of years. (I might point out that adelady and I think Eric were referring to the [CO2] threshold which, coupled with appropriate period in the Milankovitch cycles, would be required for descent from the current interglacial to glacial period).
82772. Albatross at 02:35 AM on 15 June 2011
       Examining Dr. John Christy's Global Warming Skepticism
       Les @68, Thanks for following up and exposing yet more distortion from the 'skeptics'. Why am I not surprised....?
82773. Chris G at 02:32 AM on 15 June 2011
       The greenhouse effect is real: here's why
       Oh, I just had a thought, probably not an original one, but... I've been puzzling over how we might detect when feedbacks such as permafrost melt (rot) or clathrate releases might overtake the rate of anthropogenic GHG emissions. I was thinking we'd have to wait until after a real effort was made to reduce our emissions and see how much the increase in GHG content reduced. The rate is accelerating; so, I'd first be looking for a reduction in the rate of increase rather than a leveling off. But, if you closely monitored the isotopic signature, you might be able to detect when these feedbacks started to play a significant role a bit sooner. Anyone got any references in this area?
       Response:

       [DB] If you go here, you can select your station (this one is centered on Svalbard, for example) and the GHG parameter of interest.  HTH

82774. kampmannpeine at 02:28 AM on 15 June 2011
       SkS Weekly Digest #3
       @John Cook, I would prefer to receive the "Badget" alone ... so: is that feasable??
82775. Chris G at 02:19 AM on 15 June 2011
       The greenhouse effect is real: here's why
       Arkadiusz, I'm not sure what your point is. Yes, carbon released through geologic processes will have a similar isotopic signature as long-sequestered carbon released through the burning of fossil fuels. Rocks weather more when they are exposed to weather than when they are buried under ice. Weathering of rocks draws down the level of CO2, and this tends to have a slow (very slow) balancing effect on carbon released from whatever sources. I think you are implying something, but what that is, is not clear.
82776. chris at 02:17 AM on 15 June 2011
       The greenhouse effect is real: here's why
       On the asymmetry of polar amplification under enhanced greenhouse scenarios. The delayed Antarctic response to enhanced greenhouse warming was predicted from models of various complexity from up to 30 years ago as described in a 2007 review by Manabe and Stouffer. Can't find an online version of the paper, but I summarized some of the points from that review in a post here some time ago.
82777. Tom Curtis at 02:15 AM on 15 June 2011
       Forecast: Permanently Hotter Summers in 20-60 years
       adelady @19, studies of CO2 levels over the last 500 million years show a CO2 threshold of 1000 ppm, above which ice ages do not occur. Because the sun has been warming in the long term, that threshold has probably declined (and is inexact), but is certainly not below 300 ppm. There is some argument that it is now around 400-500 ppm, but that is not a consensus opinion. Following your link, 300 G tonne release represents anthropogenic emissions to date. 1000 G tonnes release represents the budget for a 450 ppm stabilisation (from memory).
82778. michael sweet at 02:07 AM on 15 June 2011
       Websites for Watching the Arctic Sea Ice Melt
       Sphaerica, Your illustration with the boxes is really nice. Hopefully people will see it in the comments if they have trouble seeing the difference in the main post. I think it is too late to change the post now.
       Response:

       [DB] It can be done via an Addendum at the end.  If you wish, I can do it for you.

82779. Mike2811 at 02:04 AM on 15 June 2011
       Phil Jones - Warming Since 1995 is now Statistically Significant
       I'd just like to support (belatedly) Dikran's point about the incorrect interpretation of classical p-values as levels of belief. Yes the correct interpretations are hard to understand, but putting incorrect interpretations like "we could say with 93% confidence that..." does no-one any favours.
82780. Bob Lacatena at 01:58 AM on 15 June 2011
       Examining Dr. John Christy's Global Warming Skepticism
       74, Tom, I actually don't doubt that he has the education and experience. What I doubt is that he's taking the time to properly use his own personal education and skills to learn climate science. I think he can, but the rather low level of his posts to date demonstrate that he has not done so. He just needs help getting his focus on actually learning, rather than trying to jump immediately to finding the flaws in climate science without taking the time to actually build the foundation that would be needed to do so (or, in actuality, to understand how few flaws there are, what they are, what the implications are, and what is pretty solidly understood in the field).
82781. Chris G at 01:54 AM on 15 June 2011
       The greenhouse effect is real: here's why
       Paul D, I think you misunderstand CBD. I don't think he was attempting to discredit the main theme; I think he was merely asking honest questions on points that were not clear. Tom and Chris C, Thanks, I was thinking along those lines, but your answers are more clear, or at least the combination of them is, than I probably would have produced. I think if you increase the insulation qualities of the atmosphere, you end up with a more even distribution of energy, but, yeah, albedo changes through snow and ice loss also play a part, and those changes can have multiple causes. Related to the article itself, I'm thinking the greenhouse effect is more directly an effect related to energy, and temperature is really just a proxy for energy content. Different substances have different heat capacities, and winds, evaporation/precipitation, convection, phase changes (ice vs. water), are all affected by changes in energy content that may be less easy to measure than changes in temperature. Temperature is a pretty good proxy, but it isn't the only change taking place as a result of the increase in GHGs.
82782. Bob Lacatena at 01:53 AM on 15 June 2011
       Examining Dr. John Christy's Global Warming Skepticism
       66, jonicol,

       Surely the most important aspect of this discussion is to discover the underlying behaviour of a green house gas and the influence of natural climate variation which has to be understood before one can quantify the effect of CO2.

       Yes. Absolutely. And this has been done. That you do not understand it does not warrant the implication that it is not understood. As has been stated previously, there is a wealth of information readily available for anyone who takes the time to look, especially if you already have the proper foundation in the hard sciences. Your cooperation is requested in doing your best to educate yourself, either by reading the many sources of serious information available, or by asking meaningful questions here (on the appropriate threads), through which people who do understand the science can help you (and others) to learn, but please, do so without adding backhanded implications that the science is wrong. If you have serious reason to believe this is the case then you shouldn't be asking questions, and should instead be offering a substantive argument to make your case. Claiming ignorance, while simultaneously professing doubt and dropping half-arguments, is unhelpful. But asking questions -- for the sake of learning -- is good. Please go ahead and do so.
82783. Tom Curtis at 01:50 AM on 15 June 2011
       The greenhouse effect is real: here's why
       Chris Colose @8, would you care to expand on your disagreement. I'm always looking for a chance to learn more.
82784. michael sweet at 01:49 AM on 15 June 2011
       The greenhouse effect is real: here's why
       Remember that Arrhenius in 1896 predicted the fingerprints of AGW (he did not predict stratospheric cooling, the stratosphere had not been discovered yet). The fingerprints have been known for over 110 years and have been extensively tested and confirmed. This also counters the "skeptic" argument that AGW cannot be experimentally falsified. No other method of warming includes all the fingerprints.
82785. Tom Curtis at 01:46 AM on 15 June 2011
       Examining Dr. John Christy's Global Warming Skepticism
       Sphaerica @72, John Nicol claims to be a former Dean of Science at James Cook University. I have an independent reason to believe he was connected to that University.
82786. Eric the Red at 01:40 AM on 15 June 2011
       The greenhouse effect is real: here's why
       Chris, I agree. As Tom mentioned, the polar amplification is largely one-sided; large warming in the Arctic, virtually no change in the Antarctic. I do not necessarily agree that the difference is due the loss of sea ice as the Arctic warming occurs before the sea ice begins to retreat. It could amplify the warming, but the initial warming should occur at both poles. I maintain that warming of the North Atlantic had much more effect on the sea ice and temperatures.
82787. Tom Curtis at 01:33 AM on 15 June 2011
       Examining Dr. John Christy's Global Warming Skepticism
       jonnicol @66, I have commented about the tropospheric hotspot here.
82788. Tom Curtis at 01:32 AM on 15 June 2011
       Dispelling two myths about the tropospheric hot spot
       jonicol from here, you question the relevance of the 2007 IPCC AR4 because it, apparently post dated the controversy. Will you also question Santer et al, 1996. Santer et al identify the tropospheric hotspot along with the cooling stratosphere as a signature of enhanced warming found in the models. However, Santer et al conclude by saying:

       "Although we have identified a component of the observational record that shows a statistically significant similarity with model predictions, we have not quantified the relative magnitude of natural and human-induced climate effects. This will require improved histories of radiative forcing due to natural and anthropogenic factors, and numerical experiments that better define an anthropogenic climate-change signal and the variability due to purely natural causes."

       So, although Santer et al identify the hotspot as a feature of the model, they explicitly refuse to identify it as a unique feature of greenhouse warming. Indeed, the IPCC AR4. As near as I can identify, then, the difference between Santer et al 1996 and the IPCC AR4 (2007) is not that the IPCC conceals mention of the hotspot because of empirical failure. On the contrary they give it due prominence. Rather, the difference is that in 1996 (and in the 2001 TAR) it was not known whether the hotspot would be an effect of solar warming; whereas in 2007 it was known that it would be - at least according to the models. But neither in 1996 nor in 2007 was the hotspot claimed as a unique feature of greenhouse warming. You claim in Quadrant that:

       "The one modern, definitive experiment, the search for the signature of the green house effect has failed totally. Projected confidently by the models, this “signature” was expected to be represented by an exceptional warming in the upper troposphere above the tropics. The experiments, carried out during twenty years of research supported by The Australian Green House Office as well as by many other well funded Atmospheric Science groups around the world, show that this signature does not exist. Where is the Enhanced Green House Effect? No one knows."

       That claim is now seen to be wrong on several counts. First and most importantly, the hot spot was never the "one modern definitive experiment" to establish that the greenhouse effect was responsible for most of the enhanced warming of the twentieth century. There were a variety of such "experiments". If you where ignorant of these "fingerprints", you had no basis to pretend to expertise by publishing the article, and if you where not ignorant of them, ... well, moderation policy forbids. But not only was the hotspot not just the one signature, it was not even a signature of greenhouse warming. On the contrary, it is a signature of the lapse rate feedback, and expected negative feedback on warming. Modifying the models so that they no longer predict the hotspot would have little consequence on their predictions of greenhouse warming, but it would certainly reduce their prediction of one of the ameliorating factors. Now, you may be able to find a scientific paper in which the hotspot is claimed to be a unique feature of a greenhouse warming - but I do not know of it. Nor has that been at any time the general view of the climate science community. Therefore, if you where an honourable man you would withdraw your Quadrant article because of a substantial, and fundamental factual error; and would post a retraction specifying that you has made an error and the nature of that error. I would certainly like to believe of you that you where honourable in that old fashioned way that thought truth was more important than reputation. We shall see. Finally, I draw your attention to Part 2 of the article above. As you can see, the existence of the tropospheric hotspot remains an open question, and has certainly not been decided one way or the other.
82789. Paul D at 01:31 AM on 15 June 2011
       The greenhouse effect is real: here's why
       I agree with Tom Curtis, in order to be credible CBDunkerson would need to account for all fingerprints, cherry picking a few to discredit something does not increase any ones knowledge. As it stands the enhanced green house effect is robust, to dislodge it you need something that could account for existing need fingerprints and more.
82790. DSL at 01:28 AM on 15 June 2011
       Climategate CRU emails suggest conspiracy
       batvette, what Tom said. Further, just as there are different modes of production, there are different modes of consumption. The current mode in the US and other "developed" nations is consumption-as-an-economic-driver. In other words, increasing consumption is understood by economic managers (under the current mode) to be vital to the mode: consumption drives production, and production drives the generation of capital, and the generation of capital is, in this mode, synonymous with required "economic growth." Products need to be consumed or destroyed at an increasing rate, and so consumption and destruction are encouraged . . . strongly. The economy is no longer based on organic, unmanaged demand. Demand is now managed through a culture of consumption. Waste has not been a factor in the management of demand until recently. For 150 years, consumption-without-consequence has been central to the culture. Your response, "However this economy is highly dependent on consumption and the mantra of climate change is that we've got to stop consuming or we're committing a horrible sin," is an understandable expression of that culture. Has this economic mode and its culture been beneficial? Absolutely. Has it also been destructive? Absolutely. Is it in the immediate interests of those who are privileged by the mode to downplay the destruction and hype the benefit? Absolutely. I argue that smart people, even if they are privileged by the current mode, are able to shrug off the influence of the current mode and understand that other modes may be more personally and socially responsible in the long run and within the context of history. Someone once said that the current mode will allow us to fully develop the means of production, but the next mode will allow us to use those means responsibly. It's not that consumption needs to end. It's that the current mode of consumption that needs to end. It's happened before--just 300 years ago, roughly. I also find it interesting that you say "Most humans make their livelyhood engaged in one form of human industrial activity or another. Telling people they have to stop living, and it really is that brutally simple, to save the earth... how do you think they'll take that." Capitalists have been replacing people with machines for two hundred years--a kind of externalization (humanity as pollution). This replacement is a consequence of the same economic mode you seem to defend, done for the sake of more efficient production of capital. If people lose their livelihoods because we are transitioning to a more sustainable mode, should we not blame ourselves for allowing the unsustainable mode to support the growth of a long-term unsupportable population?
82791. Chris Colose at 01:21 AM on 15 June 2011
       The greenhouse effect is real: here's why
       CBDunckerson You're right that those two examples are not "greenhouse only" occurrences, and in fact polar amplification appears to be robust to not only a wide variety of forcings but a wide variety of toy modeling experiments (e.g. no high latitude ice cover, turning off evaporation feedbacks in the tropics, etc). I don't agree with Tom Curtis (#7) on this one, but I don't think amplification in the Arctic is as well understood as many people think.
82792. caerbannog at 01:17 AM on 15 June 2011
       Phil Jones - Warming Since 1995 is now Statistically Significant
       Just a rhetorical question here: Why do "skeptics" always choose the temperature data most compromised by "climategate" over the NOAA/NASA/RSS/UAH data to support their claim that the Earth has been cooling over the past decade? Like I said, a rhetorical question.
82793. Eric the Red at 01:17 AM on 15 June 2011
       Websites for Watching the Arctic Sea Ice Melt
       Sphaerica, Not sure what you mean. When have I ever said that temperatures were not rising? If you restrict your observations to record lows and highs, you may be missing the bigger picture. Are you implying that the influx of warm Atlantic waters does not impact Arctic sea ice? It sure sounds like it from your previous posts. I stand by my prediction that 2011 will not surpass the 2007 low. In fact, since sea ice is falling at a lower pace than last year, I suspect 2011 will not surpass 2010. If you believe that it will, please explain why.
82794. Bob Lacatena at 00:59 AM on 15 June 2011
       Examining Dr. John Christy's Global Warming Skepticism
       61, jnicol,

       As an aside, in my 35 years as a physicist...

       This statement is unsupported by your ignorance of the most rudimentary aspects of the science, as well as your seeming inability to research the obvious for yourself (which would save everyone a lot of trouble, since the answers that you need are very, very easily available to anyone with the background to which you lay claim). This could be a simple, emotional appeal to authority on your part. It's unclear from the context. In any event, this statement is evidence that you should have the tools to do a much, much, much better job of learning and understanding the material before speaking on it. This site, as well as others previously supplied to you, contain a wealth of information that would be of great benefit to you in your desire to actually understand the real science, rather then the dismally inadequate falsehoods upon which your current understanding is based. Please, make use of your 35 years of physics to actually learn the details and truth behind the science, and post questions rather than innuendo or repetition of ancient, thoroughly-debunked, false arguments. Please recognize that authoritatively repeating such falsehoods, even under the guise of asking for qualification and understanding, serves only to confuse and mislead more people. It's a useful thing for Exxon to do... for normal, everyday people, not so much. For them, it is directly contrary to their own self-interest. [If you had an actual, viable argument against the science that would be one thing, but repetition of the "hot spot" nonsense and other non-issues does not constitute fair and reasonable debate, it is instead just an act of terrorism, by wandering in and tossing doubt-grenades.]
82795. Tom Curtis at 00:40 AM on 15 June 2011
       The greenhouse effect is real: here's why
       CBDunkerson @4, non of the "fingerprints" are uniquely associated with a green house warming. What is uniquely associated with the greenhouse warming is the pattern of all the "fingerprints". Thus greater warming over land is a feature of any warming sourced through the atmosphere, whether greenhouse, solar, change in aerosol load or change in cloud cover, but it does rule out the surface warming as being a product of release of heat from the ocean. Greater warming at the poles is trickier. There is a subtle direct effect from greenhouse warming that warms the poles faster than the tropics. This is a consequence of the different balance between insolation and surface radiation at different latitudes: Clearly in increase in insolation will result in a greater increase in net radiation in the tropics than at the poles, because it increases the larger component of the energy budget. But likewise, a decrease in the rate at which surface radiation escapes to space will warm the poles more because that also increases the larger component of the energy budget at the poles (and the smaller at the tropics). This effect is not as strong as the different rate of warming for land and sea. Consequently, in the Northern Hemisphere, which gets progressively more land at higher latitudes until the Arctic circle is reached, this effect is reinforced. In the Southern Hemisphere, in contrast, there is progressively less land at higher latitudes until the Antarctic circle is reached, which counteracts this effect. If we reach an equilibrium temperature, temperature increases over land and sea will equalize, resulting in a stronger warming gradient in the Southern Hemisphere and a weaker gradient in the Northern Hemisphere. Finally, in the Northern Hemisphere the effect is significantly reinforced by Polar Amplification, ie, the increased summer melt of sea ice. This is a consequence of any warming, but will be slightly stronger for greenhouse warming because of the initially greater relative warming at the poles. Note that in Antarctica, the existence of a large ice covered continent surrounded by ocean prevents polar amplification, one of three features of Antarctica which make it highly unusual in terms of response to warming.
82796. Eric the Red at 00:37 AM on 15 June 2011
       Forecast: Permanently Hotter Summers in 20-60 years
       adelady, CO2 concentrations do not fall before 200 ppm until the height of the ice age, when temperatures are lowest. According to the ice core data, the temperature (and CO2 concentrations) fall slowly until reaching their minimum, then rise rapidly into the interglacial. It is entirely possible that increasing CO2 levels will prevent the Milankovitch cycle from kicking in a new ice age. That would depend upon which is the greater forcing.
82797. Bob Lacatena at 00:22 AM on 15 June 2011
       Examining Dr. John Christy's Global Warming Skepticism
       Jon Nicol, Thanks for posting on SkS. There are a few points I'd like to make concerning your comments.

       What I am looking for is something which spells out the physics of the atmosphere, the interactions between carbon dioxide, radiation and other molecules and how these cause the earth to become warmer as CO2 increases

       This is complex, and requires a serious investment of time, as well as multiple sources and avenues of education.

       Professor David Karoly recently gave a very good summary of the case made for...

       You can accept authority, or learn to understand it yourself. If you can't do the former, and commit to the latter, there's not reason to look at anything at all that is a "summary," no matter how good the presentation, or what point it is trying to make.

       ...the injection of an increased or new "forcing" into the models...

       Please avoid the use of quotes around particular words. It is frequently done by deniers, as a debate tactic, to imply disingenuous terms. I don't think that was your intent here, but forcing is a well defined and commonly used term in climate science, and as such does not need to be and should not be placed in quotations.

       ...assumed to come from...

       Not assumed. Logic and an understanding of radiative physics predicted the effect, which was then observed. Models added depth and details to the predictions. You do the science a serious disservice by implying that it is founded on whimsical assumptions when the stated ignorance of your own position (you said "What I am looking for is something which spells out the physics of the atmosphere...") does not qualify you to make such an assessment. Basically, it comes across as a cheap shot by someone who wants to deny the science.
       As Andy Pitman says, the assumption is based on the fact that carbon dioxide concentration is the only thing that has changed, so it is natural to point to carbon dioxide.This is about as wrong a statement as you can make about the science.First, as I explained, it is not an assumption. Secondly, it is not based on the premise that CO₂ concentration is the only thing that's changed. That statement is obviously false (lots of things are changing, and being measured and considered). The scientists are also not that trivially, childishly stupid. The understanding of the influence of CO₂ comes from a detailed study of molecular physics, logic, mathematical models, study of paleoclimate, laboratory experiments, real world observations, and complex computer models. To water this down to the idea that it's a trivial assumption, made merely because no one bothered to think of anything else, is patently absurd.

       ...it would only take one paper to prove that I was wrong...

       Yes. On one thing. Climate science today is a complex tapestry of thousands of ideas, observations, inferences and theories. To disprove climate science and current theory, one cannot simply grab one thread and expect the entire tapestry to unravel. A single paper may disprove a single aspect of the science, and in fact that happens frequently. That's how science advances. But the implication that someone is going to find a magic bullet that in one sweeping motion dissolves that tapestry into nothing is rather simplistically foolish. Deniers like Lindzen and others attempt to do so frequently, and always utterly fail, because climate science is not one, simple, single thread.

       ...the absence, after 25 years of dedicated searching by a large number of internationally distributed groups including in Australia, of any evidence of the "Green House Signature"...

       This is patently false. Look at the cooling stratosphere, as well as the change in winter and evening temperatures, both indicators of warming from GHG forcing. There are other clues, but you have to take the time to learn the science, instead of listening to what really is complete and utter denial trash (like the "hotspot" argument, which is such a joke that it's laughable).

       ...such was their confidence in its existence...

       This sounds like a pitiful debate tactic. Were you there? Is this how they reacted? Have you read the papers themselves? Do you have any idea what you're talking about, or are you just throwing fun phrases around? Is the idea to learn science, or to take potshots in an effort to trivialize and diminish the science, without really saying anything of substance?

       Statements... do nothing to clarify the science

       Yes, they do, because they help to dispel ridiculous myths that, as you can see from your own repeated misconceptions, the unwary can easily fall for. At the same time, your repetition of many long debunked arguments, ones that you could easily have found the answers to on this site, before you posted, further highlights the need to repeatedly attack those falsehoods, because for everyone who understands the truth, there are dozens like you, who don't understand, heard it once, believe it without thinking, and then spread it around as if it were true.
82798. adelady at 00:20 AM on 15 June 2011
       Forecast: Permanently Hotter Summers in 20-60 years
       Eric the Red "We have a million years of data showing that we will eventually enter another ice age. Unless something drastic occurs that alters that cycle. If we look at everybody's favourite animation, the Time History of CO2, we notice something. The only time ice ages have done their thing effectively is when CO2 concentrations have been below 200ppm. Unless we do some compensatory drastic thing, CO2 concentration won't be anywhere nearly low enough by the time the Milankovitch cycle should be kicking in for an ice age. And have a look at this item. http://www.skepticalscience.com/upcoming-ice-age-postponed-indefinitely.html
82799. KR at 00:13 AM on 15 June 2011
       Examining Dr. John Christy's Global Warming Skepticism
       Re my previous post - My apologies, jonicol, the multiple contradictions in a single article were from Carter's Quandrant article, not yours. My mistake. My statements about the inherent biases in data and articles from advocacy groups, however, stand. And those have to be taken into account when evaluating what's presented.
82800. Tor B at 00:10 AM on 15 June 2011
       It's cooling
       A casual review of daily averages of high-arctic (80-90 N) air temperatures over the 50-year record suggests that summer temperatures in this particular region of the Earth have decreased a smidgen over time, according to archived data at DMI’s Centre for Ocean and Ice . A discussion on Neven’s Arctic Sea Ice Blog has brought forward a couple of possible explanations for this which sound quite plausible to me, but I have no expertise in this area. Do you know of any published discernment on this?

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