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From Peru at 15:54 PM on 26 February 2012Satellites find over 500 billion tons of land ice melting worldwide every year, headlines focus on Himalayas
Tom Curtis: You said: "you need to determine what the change of temperature would have been without the effect of known short term influences such as ENSO, and the solar cycle.Foster and Rahmstorf have done exactly that and shown no reduction in the global warming trend" I believed exactly that just an hour before, but after seeing the 0-2000 meters ocean heat content/thermosteric sea level timeseries with more attention(as your previous comment suggested me to do) I realized that I was wrong. The nearly constant warming that Foster and Rahmstorf found covers just the Earth surface and the atmosphere. However 90% of the warming occurrs in the oceans...
and there the 1992-2003 warming was bigger than the 2004-2011 one. That explains the non-acceleration of sea level rise despite the ongoing accelerating meltdown.
You told me that in the previous comment...why you are now telling that global warming has not slowed down?
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Rob Honeycutt at 15:51 PM on 26 February 20122nd law of thermodynamics contradicts greenhouse theory
Ahem... Um, is this the Dunning-Kruger thread? -
climateadj at 15:11 PM on 26 February 2012Tropical Thermostats and Global Warming
My speculative hypothesis for the "Tropical Thermostat" is an anti-phased relationship between solar insolation and ocean upwelling. That is, the hotter the sun, the stronger the upwelling of cool water. At some point the rate of warming from the sun is matched by the rate of cooling from upwelling and a temperature plateau is reached. This mechanism could concievably act as a natural temperature governor across the tropics. The rate of ocean upwelling could be correlated with annual variations in a number of related phenomena, such as deep convection, trade winds, or the migation of the ITCZ. This might be relatively easy to test. For instance, a cross-correlation analysis of ARGO and solar insolation data would determine if the signals are anti-phased. That being said, I still wouldn't bet that tommorrow's tempeature plateau would be the same as today's. I imagine that the rise in the DC signal has a corresponding impact on the AC signal. -
Tom Curtis at 14:16 PM on 26 February 2012Satellites find over 500 billion tons of land ice melting worldwide every year, headlines focus on Himalayas
From Peru @28, "Global warming" refers to the background trend, not to annual fluctuations. Therefore, while the rate of increase of temperatures has slowed down, but there is no evidence that the pace of global warming has slowed. To determine whether or not Global Warming has slowed down, you need to determine what the change of temperature would have been without the effect of known short term influences such as ENSO, and the solar cycle. Foster and Rahmstorf have done exactly that and shown no reduction in the global warming trend. Therefore, in the near future when we are at a solar maximum and have an El Nino we can expect global temperature records to be smashed again. After that, of course, we can expect so-called climate skeptics to write endless blogs about how there has been no warming since 2013 or 2014. -
Rob Painting at 14:06 PM on 26 February 2012Satellites find over 500 billion tons of land ice melting worldwide every year, headlines focus on Himalayas
From Peru - "The slowdown in global warming during the last decade was real and not an ENSO + Solar driven (because of the big La Niñas + reduced solar activity in recent years) artifact? I hope you realize that none of those are mutually exclusive. We've been down this road with comments before. Some readers, for whatever reason, seem to want to pin this on one factor alone, when in fact it may be due to multiple factors. The trend toward more intense and dominant La Nina at the end of the 'noughties' has clearly affected global surface temperatures, but so too has the solar cycle, and maybe those Asian aerosols (reflective particles of pollution). The slower rate of ocean heat uptake is partially a result of the downward trend in the solar cycle through the 'noughties'. Not only did it (solar output) reach the lowest solar sunspot cycle in a century, but it also lasted 2 years longer than normal. But the solar cycle trend is now upwards, and due to the 18 month-24 month thermal lag of the oceans, we will soon see this manifest itself in global surface temperatures. See SkS posts: NASA scientists expect more rapid global warming in the very near future
Personally I find it a little troubling that all these factors lined up to cool the Earth, and yet it keeps absorbing more heat. That heat will make soon make itself felt in the next El Nino. It's lurking down there below the 100 metre layer of the surface ocean ready to pounce!
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Tom Curtis at 13:56 PM on 26 February 2012Monckton Misrepresents Reality (Part 3)
Owl905 @5, while I agree saying that the heat in the deep ocean will return to the surface in the near future is slightly inaccurate, never-the-less the heat in the deep ocean will contribute to future warming. That is because warming the deep oceans makes it harder for heat to flow to the deep oceans, so that in the near future we can expect a greater proportion of the warming from enhanced greenhouse gas concentrations and feedbacks to be retained at the surface. The effect of that will be a more rapid temperature rise. Consequently, while the language may not have been precise,the point being made was entirely accurate. -
Tom Curtis at 13:51 PM on 26 February 2012Monckton Misrepresents Reality (Part 3)
Sceptical Wombat @3, you raise an interesting point. As it happens, in his St Pauls address, Monckton accused the IPCC of "... a statistical lie known as the start point or end point fallacy" based on the same graph. That is, of course, a very different argument to that which he made in response to Dana, and which is discussed above. But while Monckton's purported reasons change, his conclusion (that the IPCC lied) never does. His argument against the IPCC in St Paul was, of course, entirely invalid. The start point fallacy is committed when just a small change in start point makes a large change in the determined trend. The way you avoid the start point or end point fallacy is you ensure that all trends shown are statistically significant. As the shortest trend shown by the IPCC is 25 years, all the trends they show are statistically significant. Therefore they did not commit the start point fallacy. It really is that simple, but you don't need to know statistics or check statistical significance to see that Monckton was entirely misrepresenting the facts of the matter. Nick Stokes has developed a trend viewer, which is available at his blog, Moyhu. The viewer shows all trends in the given data set, from any start date to any end date. To read it, you pick a start year on the Y axis, then scan across till you come to the end date that you want, on the X axis (or vise versa). The colour of the relevant point on the graph will then show you the trend. Care does need to be taken because of Nick's unusual colour scheme. Specifically, he uses the yellower shades of green to indicate small positive trends, and bluer shades of green to indicate small negative trends. When looking at shades of green, therefore, look for the grey zone indicating near zero trend to make sure you know the sign of the trend in that area. Just to confuse things further, he also uses grey between to shades of orange to indicate a strong positive trend, so those regions of grey are not to be confused with the grey sections found in green areas and indicating near zero trends. With that warning in mind, here is the HadCRUT3 plot with the end year 2005 (approximately) marked out clearly by a black border:
First, you will notice that for every trend with start year prior to 1987 that ends in 2005, the trend is positive.
Second, you will notice that for every trend with a start year prior to 1987 that ends in 2005, the general pattern is that the more recent the start year, the stronger the trend.
Third, you will notice that the same is true for all end years between 1995 and 2012, provided that you only consider trends at least 20 years in length.
The reason for the twenty year limit is only to ensure statistical significance. However, with that limit you can see that the general pattern is robust with respect to start points and end points. That is, there is no start point (or end point) fallacy involved.
I should further not that I have only used HadCRUT3 to enable direct comparison with the IPCC Graph. HadCRUT3 is less accurate than either the NCDC or GISTEMP temperature indices, and indeed is soon to be supplanted by HadCRUT4. All of NCDC, GISTEMP and HadCRUT4 show this pattern even more strongly than does HadCRUT3.
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Chris Colose at 13:46 PM on 26 February 2012Radiative Balance, Feedback, and Runaway Warming
Tom Actually Charlie is correct here. Climate scientists usually don't define the Stefan-Boltzmann response as a feedback whatsoever, but rather as the baseline relative to how other feedbacks are referenced. Take the following image for example (from Roe, 2009):
Here the y-axis is the feedback factor,f, typically associated with the equation 1/1-f. Climate sensitivity is proportional to 1/1-f. More specifically it is *equal to* CS=b/1-f where b is the response you'd get in a system that only had the Stefan-Boltzmann response operating. Thus, in the limit where we have no feedbacks, f=0 and the equation reduces to CS=b. That is, you'd get the response from just the Stefan-Boltzmann response.
In the above graph, the "all" feedback factor is positive, f=0.6 or so. This means that CS = b/0.4 = 2.5b (i.e., climate sensitivity is inflated by a factor of 2.5). Note however that the Stefan-Boltzmann response is not included in the graph.
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Search For 'Missing Heat' Confirms More Global Warming 'In The Pipeline'
neil - Even if CO2 emission halted tomorrow, and aerosols were not a factor (pretty big "ifs", mind you), there would still be some warming in the pipeline. Currently the oceans are absorbing ~40% of our emissions, call it 2ppm/yr. The climate is still catching up to emissions from decades ago. Until the oceanic drawdown zeros out TOA imbalances, we will continue to increase the energy in the climate. That means increases in surface temperatures as well as oceanic. Only when that imbalance is canceled will we see a halt in temperature increases - the two processes have quite a distance before they meet. -
Rob Painting at 13:41 PM on 26 February 2012Search For 'Missing Heat' Confirms More Global Warming 'In The Pipeline'
Neil - "The fully-coupled models used for IPCC AR4 were only 'physical' models. They did not contain carbon-cycles, so carbon could not be advected around or exchanged between natural reservoirs." And yet the IPCC AR4 has a whole chapter dedicated to coupled climate-carbon cycle projections. I have no idea why you think the AR4 would neglect something so obvious, but you can't have read the AR4 in any event. "For zero emissions, (or the commitment to past emissions), there is no future warming, as explained previously." Errr, no. The 'no warming' scenario only occurs if aerosols are held constant. Clearly that is not possible. Once the same activity, the burning of fossil fuels, ceases, so too will the reflective aerosol shield which has prevented further warming thus far. How big this future warming may be is not yet known, because we don't have a good handle on the size of the cooling effect of aerosols , nor how sensitive the climate really is. And, as I stated earlier, the carbon cycle models may not be accurately modeling the terrestrial carbon sink. Land vegetation is a strong carbon sink because of forest re-growth - especially in the tropics. See Pan (2011). But the carbon cycle models show a strong draw-down of CO2 both presently and in the future due to CO2 fertilization - increased plant growth soaking up CO2. Trouble is it isn't happening. A number of regional studies show that the CO2 fertilization effect, if it did exist in the region, has since ceased. And the most telling is Penuelas (2011), which is a global study, and likewise finds no evidence of the CO2 fertilization effect. This is troubling because the carbon cycle models project many decades worth of annual fossil fuel emissions (at the present rate) are expected to be absorbed by the proposed CO2 fertilization effect. Let's hope it kicks in at some point, or things could be much worse than currently projected. " Don't get confused between heat and temperature!! The ocean can absorb a massive amount of heat, but the average temperature of the ocean (and particulalrly the deep ocean) will remain below the temperature of the surface! Thus the direction of the heat flux remains downward!" I think you need to consider for a moment how the global surface warms. Have you never heard of evaporation, convection and conduction? How do you propose the atmosphere warms if heat only travels downwards? And don't run away - answer the question. I think it's a useful lesson in logic. -
owl905 at 13:22 PM on 26 February 2012Monckton Misrepresents Reality (Part 3)
Good dart-point responses to Moncton's mumbo-jumbo. ... except for the 'magic' about the heat transferred to the deep ocean coming back and adding to surface heating in the near term. That description: "so the heat doesn't stay there forever, and eventually the stored heat warms surface temperatures as well." ... is the type of tilt usually associated with pro-pollutionists. The fallacies are rift. SKS really needs to walk through a warming-force in the atmosphere partnered with a huge reservoir of ice-cold deep ocean currents and pools. The claim states the deep oceans are the destination of recent warming, versus recent flattening in both atmospheric and 0-700metre ocean depths. Then that heat is getting down into currents that may not surface for a 1,000 years: "The deep water slowly travels south through the oceanic abyss, eventually mixing upward to the surface in different parts of the world up to 1,000 years later." http://www.enviroliteracy.org/article.php/545.html If the gyres are the transport down, and the current is slow, the heat will also spread into the surrounding deep cold currents. It's not magic - it's the same process that warmed all spheres - atmosphere, land, and oceans - during deglaciation periods. The starting point for the analysis is to confirm deep ocean warming. Then put focus on the downward transport during three distinct sea-surface states: El Nino ENSO-neutral, and La Nina. -
Doug Hutcheson at 12:57 PM on 26 February 2012Monckton Misrepresents Reality (Part 3)
Tom Curtis @ 2, that is the Catch 22, isn't it? Scientists need to follow the scientific method in opposing the psuedo-science of people like Michaels and Monckton. Non-scientists like me could presumably take them on in civilian court action only if we could prove they are causing us harm through their actions and that would be a very slippery slope, as we non-scientists would have to rely on science to prove our case, but that is not the scientific way. The underlying problem is one of publicity, not science. Eliminating Michaels and Monckton would only result in some other sock-puppets taking their place. If only there was a Heartland equivalent working to promote truth and reality. Clever marketing is creating the political inertia and I suspect only clever marketing will be able to overcome the inertia. By the time Earth's climate is so badly dislocated that Mr. Average can understand what is happening, it will be too late. -
From Peru at 12:44 PM on 26 February 2012Satellites find over 500 billion tons of land ice melting worldwide every year, headlines focus on Himalayas
Tom Curtis: After seeing the curve again, I realized that in effect thermo-steric sea level rise slowed down after 2003. So after all,the ocean warmed less after 2004 than in 1992-2003 period? The slowdown in global warming during the last decade was real and not an ENSO + Solar driven (because of the big La Niñas + reduced solar activity in recent years) artifact? -
Tom Curtis at 12:42 PM on 26 February 2012Satellites find over 500 billion tons of land ice melting worldwide every year, headlines focus on Himalayas
Doug H @26, as I said, "...the massive and wide spread flooding in 2010 resulted in a decrease in ocean mass, also adding to the reduced trend." But thank you for the graphic illustrating the point. -
Sceptical Wombat at 12:40 PM on 26 February 2012Monckton Misrepresents Reality (Part 3)
The obvious question with the IPPC graph which shows that warming has been accelerating is to what extent it is dependent on start dates. It would be interesting to graph the rate of increase to 2005 from each year from 1856 to 1981. -
Doug Hutcheson at 12:26 PM on 26 February 2012Satellites find over 500 billion tons of land ice melting worldwide every year, headlines focus on Himalayas
Tom Curtis @ 25, What impact on sea level have the following had over the last few years?- Increased atmospheric water vapour, due to increased temperatures
- Increased precipitation over land, resulting from increased atmospheric water vapour
Would these have a measurable impact on sea levels?
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Tom Curtis at 12:00 PM on 26 February 2012Satellites find over 500 billion tons of land ice melting worldwide every year, headlines focus on Himalayas
From Peru @24, your third chart shows a clear reduction in the rate of seal level rise due to the warming of the oceans in 2004 (steric sea level rise). As steric sea level represented more than half of the total contribution to sea level rise up to that point, the surprising thing is that the rate of sea level rise did not (approximately) halve at that time. Clearly an increase in ocean mass has partially countered a decrease in steric sea level rise. It should be noted that the massive and wide spread flooding in 2010 resulted in a decrease in ocean mass, also adding to the reduced trend. -
Doug Hutcheson at 11:54 AM on 26 February 2012Global Extinction: Gradual Doom as Bad as Abrupt
JP40 @ 33, you say"settlements in space could be the only way to preserve our civilization and our species"
Even if our space settlements could survive the randomness of critical failures of equipment, or damage from the likes of meteorites and even if they had the capability to engineer replacement parts for failed equipment, I earnestly hope that they would not preserve our civilisation. After all, it is our civilised treatment of our home planet that is causing us to consider alternatives. I am saddened by the thought that all we have learned during our evolution may be lost, but I wonder whether knowledge has not been the poisoned fruit which now threatens us. If only we had never developed opposed thumbs, the world would still be Eden and humanity would be innocent of its crimes. -
From Peru at 11:29 AM on 26 February 2012Satellites find over 500 billion tons of land ice melting worldwide every year, headlines focus on Himalayas
One thing perplexes me: How can ocean mass sea level rise be accelerating (due to accelerating melt in Antartica and Greenland) while total sea level rise has not done the same thing? During 1993-2011, we have had a nearly constant rate of 3.2 mm/yr of SLR:
Even worse, for 2003-2011 the linear trend dropped to 2.55 mm/yr:
Source: AVISO
One could think that steric sea level rise (a change in sea level caused by temperature and salinity changes)has slowed, balancing the ocean mass sea level rise acceleration, but that is not true:
Source: NODC
Where is the missing sea level rise?
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Tom Curtis at 11:14 AM on 26 February 2012Radiative Balance, Feedback, and Runaway Warming
Charlie A @21, I believe climate scientists use the term "net positive feedback" to mean that the feedback including the Stefan-Boltzmann radiation term is positive, ie, that the temperature response of the initial forcing plus the feedback is larger than the temperature response of the initial forcing alone. -
Tom Curtis at 11:01 AM on 26 February 2012Positive feedback means runaway warming
David Lewis @109, in that lecture, Hansen says,"Our model blows up before the oceans boil, but it suggests that perhaps runaway conditions could occur with added forcing as small as 10-20 W/m2."
A 10 W/m^2 forcing, the lower limit of the range where a runaway greenhouse effect could be caused represents a 2.7 times doubling of CO2 concentration, or 1800 ppmv. To put that into perspective, the complete combustion of all currently known and speculated oil, gas and coal reserves would raise the CO2 concentration in the atmosphere to 1366 ppmv, or approx 8.5 W/m^2 forcing. Even where we foolish enough to do that, we could not realistically do it in a century, so there would be plenty of time to turn back from our folly. What concerns Hansen is the possible massive release of Methane from clathrates and from thawed tundra adding over 1000 ppmv of CO2 to the atmosphere; or if done quickly enough, acting as a direct forcing of much greater magnitude. Fortunately the probability of a methane release of that magnitude, or a rapid enough methane release to lift the forcing over the 10 W/m^2 level for the possibility of a runaway greenhouse effect is remote. I note that Hansen indicates that the run away effect is a "dead certainty" not only if we consume all coal, but also all tars (shale oil & tar sands). That indeed would lift CO2 concentrations above his lower limit for possibility, which together with a clathrate gun is would lift CO2 concentrations beyond the level where his model blows up. Again, however, this is not a prospect for this coming century because we cannot consume the coals fast enough on any likely economic scenario. More to the point, Hansen is simply wrong about this prospect, as is elegantly discussed by Chris Colose in his recent blog post on SkS. The upshot is, if we go for a suicide pact (burn all tars and coal), we can in fact make large portions of the planet literally uninhabitable by warm blooded creatures; but we cannot turn Earth into another Venus, or extinguish all life on Earth. (If nothing else, hypothermophiles will continue to hold on in geysers and ocean ridges. I'm sure that is a comforting thought. -
YOGI at 10:57 AM on 26 February 20122nd law of thermodynamics contradicts greenhouse theory
I will read the Trenberth guest post and comment later, thank you. -
Tom Curtis at 10:32 AM on 26 February 2012Monckton Misrepresents Reality (Part 3)
JoeTheScientist @2, No! And nor do we want to. Even on an issue so important, science works by the open exchange of ideas. Well, actually it works by the open and honest exchange of ideas, so what Monckton does is anti-science, but because of the way science works, it can only defend itself by the open exchange of ideas. As soon as scientists think they can rely on more than that, they kill that which they are trying to defend, as Lysenko did in the Soviet Union. -
IanC at 10:26 AM on 26 February 20122nd law of thermodynamics contradicts greenhouse theory
Yogi 1338, If, hypothetically speaking, the source of heat on earth is internally generated, would you, in this case, agree that the earth will be warmer with water vapour present compared to the case without?Moderator Response: [JH] Please do not feed the troll. -
YOGI at 10:24 AM on 26 February 20122nd law of thermodynamics contradicts greenhouse theory
"[DB] You are advised to read the entire thread above, as your fallacy has been corrected several times already." Nutshell it for me now if you can, unless you can link me to the relevant comment, I`m not going to read all the comments for it.Response:[DB] If you cannot be bothered to read work already done, there for inspection, then why should anyone here engage you? Perhaps if you succinctly narrow down your objection to the one thing you want to hang your hat on then someone here will be able to help you.
Unless your goal is to simply waste the time of others. As also has been evidenced on this thread.
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YOGI at 10:20 AM on 26 February 20122nd law of thermodynamics contradicts greenhouse theory
Response: [JH] Your propensisty to post factoids without context...... It was not out of context. I was commenting on the SOD link at #1333. And the data shows that daily min/max soil temp`s range less than the atmosphere.Moderator Response: [JH] You are skating on very thin ice. Please cease and desist. -
solarsparky at 10:16 AM on 26 February 2012Satellites find over 500 billion tons of land ice melting worldwide every year, headlines focus on Himalayas
Excuse my ignorance, what does,"the red spot in Africa is an artifact" mean and why do we have blue spot in the Pilbara region of WA,yes there is geological evidence of ice sheets at Marble Bar, but certainly not in the time these satellites have been recording data? -
YOGI at 10:12 AM on 26 February 20122nd law of thermodynamics contradicts greenhouse theory
#1336 "Are you warmer if you cover yourself in a blanket than you would be without the blanket? Yes of course you are, because the blanket back-radiates some of your body heat." Unlike the Earth I am internally heated so the analogy is not safe, but if the blanket is bright white, it could be handy to reflect the sunshine on a really hot day. But for an externally heated system such as Earth, to have 235W/m go in and out, but to reach 390 watts within the system is impossible: [link]Moderator Response:[DB] You are advised to read the entire thread above, as your fallacy has been corrected several times already.
Additionally, you would be wise to read this guest post by Dr. Trenberth for yet further exposition into the subject. It contains this updated version of the graphic you link:
[RH] Hotlinked url that was breaking page format.
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JP40 at 10:12 AM on 26 February 2012Global Extinction: Gradual Doom as Bad as Abrupt
The technology needed for accomplishing a task isn't a guarantee to it getting done. We see this now with space travel exploration, but it also applies to climate change issues. Just because we know how to build wind turbines, solar plants, indoor airoponic farms, and sea barriers, doesn't mean we will be able to stop a collapse of civilization due to climate change and overpopulation related problems. The main problem in the western world, and especially America is the capitalist economy. A large corporation, as a collective entity of people pursuing their personal goals, has absolutely no intrest in reducing its profit margins, in the long term intrest of helping our civilization survive. That, and the fact that politics works a similar way, with politicians only concerned about getting reelected, Is the main reason why climate change denial is so wide-spread. In WW2, the government ordered car companies to start making tanks, jeeps, and aircraft. If a strong-willed president tried that today, with renewable energy, he/she would be called a commie and would get almost no support from congress. Technology is useless if the power behind the money needed to implement it won't act in the long-term best intrest of its people. -
JP40 at 09:22 AM on 26 February 2012Global Extinction: Gradual Doom as Bad as Abrupt
Bernard J. - I agree with you that for humanity to survive on earth, and for the earth to survive, we need far fewer people living on it. But, I strongly dissagree with your dismissal of the possibility of colonizing space. The amount of energy required for moving people that far is mostly irrelevant, because there is no friction in space. After a spacecraft reaches its cruising speed, it doesn't need to fire its engines until it reaches its destination. As Robert Heinlein said "Get to low earth orbit and you're halfway to anywhere in the solar system." Most of the massive Saturn-5 rocket that sent the Apollo astronauts to the moon was just to get the rocket out of the atmosphere. We have the technology right now to colonize the moon and put a permanent outpost on Mars. It's only a matter of a government putting the 20-30 billion USD required into its space program. The only other issue is time. Using our current rocket technology, it takes 1-2 earth years to get to Mars. I liken it to the age of exploration in the 1500s. Where people decided to get on a boat and start a new life in the "new world." People then couldn't imagine that now we can cross the Atlantic in a few hours. With radiation protection, people could live their entire lives on Mars, or rotating space stations. Probably not on the moon, because of the affects of low gravity on people. Getting back to the topic, if human damage to the environment triggers the same chain of events as in the P-T extinction, settlements in space could be the only way to preserve our civilization and our species. As Carl Sagan said "All civilizations become either spacefaring or extinct." -
owl905 at 08:53 AM on 26 February 2012Radiative Balance, Feedback, and Runaway Warming
@Saurj 16 - thanks for the expansion. For the purpose of ChrisC's review, maybe ppmv would work. @ChrisC - After three rounds of Moncton and the greatest extinction in the history of earth, explaining blackbody, sensitivity, and the temperature/gas dance with a few simple graphs ... is a grand slam. Maybe you could send this to the guys at The Big Bang Theory ... even Penny might get this one. -
JMurphy at 08:29 AM on 26 February 2012Medieval Warm Period was warmer
cjshaker, there's a nice 'hockey-stick' available at the first link you provided :
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Charlie A at 08:25 AM on 26 February 2012Radiative Balance, Feedback, and Runaway Warming
This is an areas where semantics and precise meanings DO matter. Many climate scientists use the term "net positive feedback" to mean that all second order feedbacks other than the Stefan-Boltzmann radiation term are positive. That is quite different than a true net positive feedback, where the positive feedbacks are larger than the negative feedback of ithe increase in radiation caused by the increase in temperature. -
YOGI at 08:20 AM on 26 February 20122nd law of thermodynamics contradicts greenhouse theory
#1333 S.O.D. article: "Notice that DLR does not drop significantly overnight. This is because of the heat capacity of the atmosphere – it cools down, but not as quickly as the ground." http://scienceofdoom.files.wordpress.com/2010/07/dlr-billings-ok-1993-2wks.png Thats bigger than some of the seasonal variation !Moderator Response: [JH] Your propensisty to post factoids without context is wearing very thin. It's like someone throwing gobs of paint against a wall and hoping that some will stick. At the end of the day, the wall is a complete mess. Please cease and desist. -
Bob Lacatena at 08:09 AM on 26 February 20122nd law of thermodynamics contradicts greenhouse theory
Yogi, Let me state this clearly. You are wrong and confused. You are religiously clinging to a misunderstanding of the science. You do not need Dikran or anyone else to walk you, step by painful step, through the thought process. What you need is to simply say to yourself "gee, maybe I don't understand all this, and I should open my mind, and go read and learn, and then come back when I have a better understanding of things." Trying to convince everyone else that you know better than all of science is a waste of everybody's time. -
Dikran Marsupial at 07:58 AM on 26 February 20122nd law of thermodynamics contradicts greenhouse theory
YOGI Sorry, nobody can say I haven't been extreemly patient with you, but again you are playing word games. Nobody has said that back-radiation makes the surface warmer, just that it makes the surface warmer than it would otherwise be. Are you warmer if you cover yourself in a blanket than you would be without the blanket? Yes of course you are, because the blanket back-radiates some of your body heat. Likewise the back radiation from GHGs causes the earth to loose the heat it gains from absorbing visible and UV light from the sun more slowly by returning some of the out-bound IR back to the surface. I have had more than enough of this discussion; had you behaved better I would continue, but life is just too short. -
YOGI at 07:44 AM on 26 February 20122nd law of thermodynamics contradicts greenhouse theory
#1331 If I agree that the back-radiation from the water vapour causes the ground to be warmer than it would otherwise be, that is paramount to saying that it heats the ground. It does not and cannot, as it is colder than the ground, it merely slows the rate of cooling, not warms it. -
scaddenp at 07:42 AM on 26 February 20122nd law of thermodynamics contradicts greenhouse theory
YOGI - you can verify some of this by actually comparing the measured backradiation in a desert compared to somewhere humid. Remember this is measurable properties here. Eg look at the SoD articles on DLR. In part one, you see the spectra for incoming versus outgoing. In part two, there is DLR measurements for Alice springs versus Billings OK. Read and understand. -
YOGI at 07:39 AM on 26 February 20122nd law of thermodynamics contradicts greenhouse theory
#1325 There are some absorption bands in the solar IR but plenty gets through. And IR penetrates into the surface of land like radio waves do. http://en.wikipedia.org/wiki/File:Solar_Spectrum.png [Snipped] -
Dikran Marsupial at 07:39 AM on 26 February 20122nd law of thermodynamics contradicts greenhouse theory
YOGI O.K. well lets revisit the original question, which was: "So what happens in a desert at night, does the CO2 back-radiation turn off when the sun goes down ?" We now know the answer, it isn't that the CO2 back-radiation turns off when the sun goes down, it cools more quickly because there is less back-radiation from water vapour because the atmosphere above the desert is drier. In fact the rapid cooling of the desert at night is a common example used to demonstrate the existence of back-radiation. Now your most recent post is essentially just blatant rhetorical evasion. If the back-radiation from water vapour causes the surface to "cool down slower", then at any point in time after nightfall it will be warmer than it would be if the water vapour were not there, precisely because of the difference in the rate of cooling. The reason why you want to evade admitting that the back-radiation causes the surface to be warmer than it would be if the water vapour were not there is obviously because you would then be forced to concede that the surface would be warmer than it would otherwise be if not for the back-radiation from CO2. Frankly getting to this point has been like getting blood out of a stone, and I can't see why you should think anyone will be willing to engage in a scientific discussion with you if you are going to behave in this manner. I am sorry to have to strongly suggest to everybody "DNFTT". -
Dikran Marsupial at 07:29 AM on 26 February 20122nd law of thermodynamics contradicts greenhouse theory
Can I suggest we ignore YOGI's comment above until we have reached the end of the discussion about deserts. The errors in YOGI's post about solar IR are pretty obvious and begging for an answer, but it would be better if the answer were delayed for a while. -
YOGI at 07:27 AM on 26 February 20122nd law of thermodynamics contradicts greenhouse theory
#1327 No it causes it to cool down slower. -
YOGI at 07:26 AM on 26 February 20122nd law of thermodynamics contradicts greenhouse theory
#1325 Solar near IR is forty something % of the heat input from the Sun. You never heard of IR blocking windows ? its the solar thermal IR they are blocking, not DLR. -
Dikran Marsupial at 07:23 AM on 26 February 20122nd law of thermodynamics contradicts greenhouse theory
YOGI I didn't say that it would warm the surface up, I said it would be warmer than it would if there were no water vapour in the atmosphere (and therefore no back-radiated IR). Do you agree that the back-radiated IR from the water vapour in the atmosphere would cause the surface to be warmer than it would be if the water vapour were not there? -
YOGI at 07:18 AM on 26 February 20122nd law of thermodynamics contradicts greenhouse theory
No, it just reduces the rate of cooling, it cant warm it up. -
scaddenp at 07:16 AM on 26 February 20122nd law of thermodynamics contradicts greenhouse theory
"Insulation, it cant warm the ground though unless its warmer than the ground." The "insulation" effect is radiative. A quick look at the thermal properties of moist air (conductivity, heat capacity) cf dry air, would tell you that conductive insulation isnt at work. Do the math. As to your "greenhouse". Incoming radiation from sun isnt in IR range (that is whole point) so no, it would heat up slower. If you have really read the SoD articles explaining the science here, you are showing little evidence of it. -
Chris Colose at 07:12 AM on 26 February 2012Radiative Balance, Feedback, and Runaway Warming
corrected- thanks -
keithpickering at 07:10 AM on 26 February 2012Radiative Balance, Feedback, and Runaway Warming
Very clear explanation, and excellent graphs, thanks. One quibble: From these figures, we can readily see the fallacy is "positive feedbacks imply instability" type arguments. ... should read "the fallacy in" -
Dikran Marsupial at 07:07 AM on 26 February 20122nd law of thermodynamics contradicts greenhouse theory
YOGI O.K., so you agree that the water vapour re-radiates some IR photons back to the surface. Would you agree that these back-radiated IR photons cause the surface to be warmer than it would be if those molecules of water vapour were not there? -
skept.fr at 07:03 AM on 26 February 2012Tropical Thermostats and Global Warming
As I understand the question, there is really a kind of thermostat (figure 1 from Argo is clear, and most of the warmer T probably come from the 30°S-30°N zone, so the rapid fall beyond 28-30 °C is probably not an artifact as suggested by Jeff on #6). But nothing says in the theory and the observations that the maximum value of this thermostat is constant when the climate is forced (or when it is different from now): we could have a future thermostat treshold at 32, 33, 34... °C, as we had past SSTs (and thermostat maximum values) hotter than now. Chris #12 : isn't Lindzen's "Iris Effect" a kind of tropical thermostat (less cirriform clouds > more IR radiation escaping to space)? If so, it took less than 20 years, the seminal paper about Iris is rather published in 2001.
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