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Comments 129351 to 129400:

129351. Patrick 027 at 07:03 AM on 20 November 2008
        Arctic sea ice melt - natural or man-made?
        chris - "The effect on the plant stomatal index might have contributions from a temperature response rather than from a drop in atmospheric CO2." I would think it has to have such contributions - a 295 ppm variation over that time period would mean there was negative CO2 (antimatter? :) ) in the atmosphere at some point! (If according to X, A or B is possible, but not C, and according to Y, B or C is possible, but not A, then X+Y = B possible, A and C not possible.) And perhaps a review of what is meant by Well-mixed GHGs: Substances or phases can become well mixed when the time period of mixing is considerably shorter than that of sources and sinks (chemical and/or physical reactions or any other external sources or sinks). Clouds are not well-mixed because cloud droplets and ice crystals are forming, growing, combining, changing into eacher, and precipitating (in some cases evaporating within another air layer) etc, faster then the wind can stir them up (and stirring itself can drive these processes - mixing fog on the one hand, downdrafts from cold dry air impinging on the side of thunderstorm and causing evaporative cooling on the other hand). Water vapor evaporates from wet surfaces and also from haze particles and clouds themselves sometimes and is also removed by condensation. I don't know as much about ozone - my impression is that within the stratosphere it may be regionally mixed but there are still large latitudinal variations at any one time. Ozone of course is produced and consumed by chemical and photochemical reactions (there are, I think, siginificant differences in reaction rates between the troposphere and stratosphere. Perhaps for water vapor, too? - some of the water vapor above the tropopause gets there by oxidation of methane. Anyway...). Aerosols are also not well mixed, although some can linger in the stratosphere once there for a while. CH4 does oxydize over a decade or two, but not fast enough to avoid becoming well-mixed - at least within the troposphere (I'm less clear on upper-atmospheric variations - there are photochemical reactions that can occur a lot more up there, of course - but only H would escape to space significantly, and that's only over geologic time periods, I think (?).). This doesn't mean it's perfectly mixed over the whole air mass. Particularly near the surface, there will be heightenned concentrations near sources and immediately downwind at any given time, and there could be some regional variations. But the larger-horizontal scale variations will be small in proportion to the average. And so on for CO2. There are significant seasonal variations in CO2, but not so much that this is important for climatic effects. Also, GHG variations near surface sources and sinks are less relevant to climate effects because the lower-level air's temperature tends to be close to the surface temperature (except maybe on calm clear nights over land) - and it's only x% of atmospheric mass (~ 6 or 10% if we're discussing atmospheric boundary layer over the whole globe).
129352. chris at 04:54 AM on 20 November 2008
        Arctic sea ice melt - natural or man-made?
        Re #333 A couple of other points Arkadiusz: You refer me to two links concerning ice core data. The first one is this: http://www.jennifermarohasy.com/blog/archives/002176.html The second one is this: http://www.realclimate.org/index.php/archives/2007/04/the-lag-between-temp-and-co2/#more-430 The RealClimate link seems entirely satisfactory. It's an excellent account of the ice core data on temperature and CO2 measures during ice age cycles. What point are you trying to make? The second link is to a blog by a certain jennifer marohasy. She seems to be a senior person at a think tank in Australia (Institute of Public Affairs), and produces/disseminates misrepresentations of the science on environmental matters. The Institute of Public Affairs is part funded by irrigation companies, logging/timber companies, cigarette companies, mining companies. In other words she's involved in the sort of attempted misrepresentation of important scientific matters in support of corporate interests. So rather similar to the US "think tanks" that told untruths about the links between ciggie smoking and cancer/respiratory and circulatory disease; untruths about the links between aspirin taking and Reyes syndrome in children; untruths about the links between chlorofluorocarbons and depletion of high atmosphere ozone...and so on. Now you may consider that it's appropriate to misrepresent the science on important issues, so as to benefit particular interests. However, I hope you would recognize that if one wants to understand what the science says/means, these sorts of institutions (and their websites) are dismal sources. One might unfortunately put Jaworowski in a similar "camp". He seems to want to create a false impression of the science on ice cores and paleoproxy CO2 measures. I'd be very interested to know what he thinks will be achieved by trying to cheat us in this way....
129353. Mizimi at 04:35 AM on 20 November 2008
        Global warming stopped in 1998, 1995, 2002, 2007, 2010, ????
        "Alternatively, Camp 2007 adopts an empirical approach to calculate solar influence on global temperature. He determines the solar cycle contributes 0.18°C cooling to global temperatures as the sun moves from maximum to minimum. Employing back of a napkin calculations, TSI would need to fall roughly 4.3 W/m2 to provide 0.6°C of cooling." Isn't this what the graph shows? Lows of around 1360.25 to highs of 1363.5...roughly 3.25W/m2 or around .45C of cooling?
129354. chris at 04:22 AM on 20 November 2008
        Arctic sea ice melt - natural or man-made?
        Re #333 Arkadiusz, ONE: plant leaf stomatal index of past CO2 levels. I'm not sure where you get your "..CO2 jumping - even above 100 ppmv by ~ forty - fifty years."! You've brought two stomatal index papers to our attention. These are: F. Wagner et al. (2002) "Rapid atmospheric CO2 changes associated with the 8,200-years-B.P. cooling event" Proc. Natl. Acad. Sci. USA 92, 12011-12014 and: T. B. van Hoof et al (2008) "A role for atmospheric CO2 in preindustrial climate forcing" Proc. Natl. Acad. Sci. USA 105, 15815-15818 In the first one (Wagner et al, 2002) plant leaf stomatal proxy CO2 levels were reconstructed to vary by around 295 +/- 10 ppm over a period of around 2000 years (8700 BP - 6800 BP). That's certainly not consistent with Beck's massive jumps over short periods. In the second one reconstructed atmospheric CO2 levels varied by around +/- 10-15 ppm over a period of around 500 years. So neither of these is really consistent with Beck. One might make the conclusion that the ice core CO2 data is somewhat "smoothed" out by averaging of atmospheric CO2 over a period of several years before the air in the firn is sealed off (see my post #330 above and discussion of formation of polar ice) . However the stomatal index reconstructions don't show wild and massive up and down jumps of atmospheric CO2. One should also be a little careful in assessing the stomatal index CO2 reconstructions. As you may know, the analysis is based on observing the size/number of the stomatal pores in plant leafs, with the assumption that as CO2 levels rise the plants respond by reducing their stomatal pore density (I think that's right!). However there is still quite a bit of controversy amongst the pactitioners themselves as to how reliable the proxy CO2 levels are. If you look at the two papers cited one can see that the error bars are very large (e.g. in the Wagner et al paper they encompass up to almost the entire range of CO2 variation). One might also question whether the stomatal index varies with temperature; e.g. the cold spell near 8200 BP studied by Wagner et al (2002) is though to be due to the collapse of the remnant of the Laurentide ice sheet as part of the late stage of the deglaciation into the Holocene. The effect on the plant stomatal index might have contributions from a temperature response rather than from a drop in atmospheric CO2. But whatever the relatively small disagreement between the stomatal plant proxies for CO2 and the ice core measures, all of the paleoproxy reconstructions of atmopsheric CO2 show reasonably steady CO2 levels before the preindustrial age. They certainly don't display "Beck-style" massive up and down jumps. And of course we know exactly why Beck's "analysis" shows massive up and down jumps. Much of the data he presents is from data measured in cities. If one looks a some of the original papers that Beck trawls through for his "analysis" one finds that "atmospheric CO2 levels" jump by 40 ppm from the morning to the afternoon, for example. That's what happens in cities! We don't need to pretend to be taken in by Beck's ludicrous misrepresentation. A more detailed critique is described here (see post #172): http://www.skepticalscience.com/solar-activity-sunspots-global-warming.htm TWO: historical paleotemperatures in Fontainebleau. I don't see your point in directing us to this paper. It seems a nice paper: i.e. N. Etien et al. (2008) "A bi-proxy reconstruction of Fontainebleau (France) growing season temperature from A.D. 1596 to 2000" Clim. Past, 4, 91-106 It shows a very typical proxy temperature evolution over the last 140 years that indicates that the region of Fontainebleau in France is warmer now than it's been in the past. As the authors conclude their abstract: "The persistency of the late 20th century warming trend appears unprecedented." What did you consider significant? The delta 13C spikes that you note are not necessarily very significant. Again the authors state that one needs to be careful in interpreting delta 13C data from timber; they say: "...This argument acts against the use of delta-13C measurements for long term temperature reconstructions despite the fact that it can slightly improve reconstructions for the 20th century." Again, this paper seems entirely consistent with our understanding of the climate in Europe during the last 200 years. It doesn't really bear on Becks nonsensical analysis at all. Remember that when we are considering atmospheric CO2 concentrations we are interested in the globally averaged levels, and aren't interested in the sort of local effects that make Beck's analysis completely useless.
129355. Arkadiusz Semczyszak at 00:09 AM on 20 November 2008
        Arctic sea ice melt - natural or man-made?
        Chris OK by Drake Chris Sorry about 230 instead 320 - these literals errors - it’s may frequent mistake. “The data are very noisy with large errror bars” - ice core only error bars, but too very large error - Chris, You known discussion by: http://www.jennifermarohasy.com/blog/archives/002176.html , and http://www.realclimate.org/index.php/archives/2007/04/the-lag-between-temp-and-co2/#more-430 “poor master Beck”? What about big maximum δ13C ~1730 in France (Fonteinblau ) and two maximum ~1950 years? What about stomatal index, C4 index?, these is indicate on a CO2 jumping - even above 100 ppmv by ~ forty - fifty years ! “poor” it’s only We (1% global product We must pay whit humbug AGW - Stern rapport) Philippe Chantreau I’m propose You on first: http://www.biokurs.de/treibhaus/180CO2/180CO2-D.pdf - here is reply of comments by H. Meijer, by R. Keeling. “nowhere to be found in Nature” - if We don’t understand it - not explain - it’s not exist? I’m suggested: - grassland - You mast reading - Global Change: Effects on Coniferous Forests and Grasslands (Breymeyer et al 1996) especially tropical pampas - they has very different NPP and very high soil, detritus, humus accumulations… (soil I think, it’s don’t appreciate the source and sink Beck’s CO2 - remind you for example ‘Biosphere 2’ experiments) - coccolith maybe same one coral - read for example early comment at “Phytoplankton Calcification in -CO2 World” ; and particularly: Macedo, MF, Duarte, P., Mendes, P. and Ferreira, G. 2001. Annual variation of environmental variables, phytoplankton species composition and photosynthetic parameters in a coastal lagoon. Journal of Plankton Research 23 : 719-732. Macedo, MF, Duarte, P., Mendes, and P. Ferreira, G. 2001. and Trichodesmium, Montastraea cavernosa, denitrification bacterial - in High CO2 - acid sea atmospheric N2 assimilations - coccolith and coral relationship... You must it known… …too match subject by this post…
129356. Philippe Chantreau at 19:26 PM on 19 November 2008
        Arctic sea ice melt - natural or man-made?
        Beck's take on wild CO2 variations is ludicrous. Not only it's not there in the data but his proposed mechanisms (biomass) to explain it are nowhere to be found in Nature.
129357. Philippe Chantreau at 18:59 PM on 19 November 2008
        Arctic sea ice melt - natural or man-made?
        Beck's take on wild CO2 variations is ludicrous. Not only it's not there in the data but his proposed mechanisms (biomass) to explain it are nowhere to be found in Nature.
129358. chris at 11:31 AM on 19 November 2008
        Arctic sea ice melt - natural or man-made?
        Re #324/328/329 Becks analysis is clearly rubbish. See for example: http://www.skepticalscience.com/solar-activity-sunspots-global-warming.htm (see post #172) And of course the links that Arkadiusz cites in his posts don't support Beck at all (Beck's a schoolteatcher btw). For example: ONE: Arkadiusz suggests we look at Phytoplankton Calcification in a High-CO2 World” : M. D. Iglesias-Rodriguez, et al. Science 320, 336-340,2008 (note that the volume number is 320 not 230) The data is summarized in Figure 4 of that paper which shows average coccolithophore mass as a function of time during the last couple of hundred years; high mass is proposed to correlate with high CO2 concentrations. The data are very noisy with large errror bars, but the smoothed fit matches very well with the atmospheric CO2 data from the Siple ice core, and (since 1959) with the Mauna Loa observatory data. In other words the paper is entirely inconsistent with Becks ludicrous "analysis" of CO2 levels jumping up and down wildly during the 20th century, and entirely consistent with the high resolution atmospheric CO2 record from Mauna Loa and ice cores. TWO: Arkadiusz suggests we look at a truly harebrained "analysis" of ice core CO2 data from the Fuji Dome core in Antarctica on some person's website ("JJ Drake"). Let's first of all take the nonsense presented there at face value. Does it support Beck's attempt at pretending that atmospheric CO2 levels jump up and down all over the place by vast amounts in very short periods? Not really. JJ Drake's "analysis" artefactually smooths out the atmospheric CO2 record of around 400,000 years such that it is largely constrained in a tightish band near 325 ppm (keep this number in your mind for later). So that's also entirely inconsistent with Becks notion of massive jumps up and down in atmospheric CO2 levels. It's worth pointing out the blatant error in "JJ Drake"'s "analysis". JJD has ignored his own mantra (see top of page of his website) that "Correlation is not Causation", and pretended that a correlation is a causation. Here's the problem: JJD has noticed a Figure (Figure 2) in a paper in which the Antarctic Fuji Dome core CO2 record is described: K. Kawamura et al. (2003) "Atmospheric CO2 variations over the last three glacial–interglacial climatic cycles deduced from the Dome Fuji deep ice core, Antarctica using a wet extraction technique" Tellus B 55, Issue 2, Pages 126-137 In the Figure (reproduced in JJDrake's website that Arkadiusz Semczyszak links to in post #329), the trapped CO2 concentrations are plotted as a function of time, and show the very nice glacial/interglacial record observed in all of the cores from Antarctica and Greenland. Also plotted is the difference in age between the ice and the trapped gas (dIG = delta ice/gas) as a function of time through the core. JJDrake notices that there is a correlation. If one plots the dIG as a function of measured [CO2] one gets a reasonable straight line that extrapolates back to 325 ppm at dIG=0 (remember that number from above?). JJDrake then attributes a spurious cause to to this correlation, namely that the CO2 somehow disappears/is destroyed from the trapped ice, and the rate of this disappearance is proportional to the age diference between the ice and the trapped air. Is there any physical/chemical basis for this assumption? JJDrake doesn't give us any. And what's the effect of "compensating" the ice core record by assuming Drake's fictitious non-defined causal relationship between dIG and magical disappearance of CO2? It effectively smooths out the record so that the CO2 concentrations are pretty close to 325 ppm for the past 400,000 years. O.K that's pretty silly. But do we know why there is a correlation between the atmospheric CO2 levels in the core and the dIG value (remember dIG is delta-ice/gas, the difference in age between the gas trapped in the core and the surrounding ice)? Yes, of course. We just need to read Kawamura et al (2003), the very nice paper that "JJDrake" has attempted to trash: It's very well known, since this can be measured directly in newly forming polar ice, that there is a time delay between snow deposition and the sealing off of the air that circulates through the loosely packed new snow that is in the process of becoming ice (called "firn"). Thus the ice is a bit (sometimes a lot) older than the trapped air bubbles within it. If snow is deposited quickly, then in general the air circulating through the firn and equilibrating with the atmosphere is trapped relatively quickly, and there isn't much difference between the age of the air and the age of the surrounding ice (in a core, for example). And vice versa. In Antarctica snow deposition is slow (allowing very long time period cores to be drilled), and so the dIG values are in general large. Remember that the rate of snow deposition is a major factor in determining the dIG value. When is snow deposition in the Antarctic fastish? It's during warm periods when atmospheric moisture levels are higher. So when it's warmer (interglacials) the firn seals off more quickly and the dIG value is smaller. During glacial periods the atmosphere is much colder, the air is dryer, snow deposition is very much slower, the firn seals off much more slowly, and so the air in the firn equilibrates with the atmosphere for much longer periods and is therefore much "younger" than the surrounding ice when it is eventually trapped...dIG is larger. So the correlation does have a causation. If JJDrake had bothered to read the paper rather than just cut and pasted a Figure from it, he wouldn't have made such a dull blunder... and so on. We could have a look at a few more of Arkadiusz Semczyszak's "links" and see whether any of thoe others supports poor master Beck!
129359. Mizimi at 05:43 AM on 19 November 2008
        Water vapor is the most powerful greenhouse gas
        Apologies for the format, the spaces that should have been there seem to have been ignored in uploading. try again: The figures given indicate the relative contribution of GG's to global warming as a % of the whole, ie +33C WV from natural sources 94.999%: manmade 0.001% CO2 from natural sources 3.502%: manmade 0.117% CH4 from natural sources 0.294%; manmade 0.066% NO2 from natural sources 0.903%: manmade 0.047% Rest ....................0.025%: manmade 0.047% The basic data is available from the DOE website ( other than they ignore WV as a GG) "Current Greenhouse Gas Concentrations"; " Greenhouse Gases and Global Warming Potentials" From the IPCC "Warming Potentials of Halocarbons and Greenhouses Gases"
129360. Mizimi at 05:09 AM on 19 November 2008
        Human CO2 is a tiny % of CO2 emissions
        Dynamic: Characterized by continuous change, activity, or progress: a state of non-equilibrium. Equilibrium: . A condition in which all acting influences are canceled by others, resulting in a stable, balanced, or unchanging system. 'Dynamic equilibrium' is thus an oxymoron. Climate is a dynamic system and fluctuates,(sometimes quite severely as history shows)and for man's purposes we would like those fluctuations to be constrained within certain limits. To my knowledge, nobody has defined what those limits should be. (??) Neither do we have the ability to alter in any meaningful and expiditious way the major active components in the system without causing ourselves serious economic problems....it will be interesting to see what effect the current global economic crisis has on fossil fuel consumption, CO2 concentrations and GMT.
129361. Arkadiusz Semczyszak at 19:49 PM on 18 November 2008
        Arctic sea ice melt - natural or man-made?
        Philippe Chantreau Beck is no "professor." = he’s not right? Harro Meijer and Ralph Keeling having betters arguments… I propose you - Yet see else only: http://homepage.ntlworld.com/jdrake/Questioning_Climate/userfiles/Ice-core_corrections_report_1.pdf I don’t agree with everything what is in this paper, but it’s interesting and I think very important in the IV report IPCC context.
129362. Quietman at 14:50 PM on 18 November 2008
        Arctic sea ice melt - natural or man-made?
        Philippe Re: Beck is no "professor." Nit picking. The papers linked do support Beck.
129363. Quietman at 14:47 PM on 18 November 2008
        Arctic sea ice melt - natural or man-made?
        Arkadiusz Thank you for the links.
129364. rob at 11:36 AM on 18 November 2008
        Temp record is unreliable
        Chris said, Notice that one doesn't need a huge number of "temperature recording stations" to assess changes in global temperature. Now I am glad she mentions this, there are enough rural sites certainly in the US that will give complete coverage, these rural sites show NO significant warming since 1900. Because of this problem (no warming) Hanson/Giss use over 1100 US weather stations many urban so they can then manipulate the raw data to push their cause. http://www.youtube.com/watch?v=LcsvaCPYgcI http://www.climateaudit.org/?p=1859 http://www.climateaudit.org/wp-content/uploads/2007/08/peters27.gif Chris says, So one needs to be clear about what the surface temperature anomaly means and how this is determined before attempting to trash it! [you might read the relevant descriptive papers here [*****]. Notice that in relation to the subject of this thread, the Earth's temperature anomaly progression under the influence of a marked 20th (and especially late-20th) century warming is essentially UNCHANGED if the ENTIRE SET OF URBAN STATIONS IS OMITTED from the analysis. Fortunately, there are FAR MORE RURAL stations than urban stations, so it is NOT ESSENTIAL to employ the urban data in analysis of global temperature change.”] So the "urban heat island effect" is somewhat of a red herring (or a stalking horse) in the context of global temperature anomaly measures. I SAY PERHAPS CHRIS SHOULD TELL HANSON THAT. PERHAPS CHRIS CAN INFORM US WHY HANSON USES STATION PAIRS INSTEAD OF USING THE PRISTINE RURAL STATION DATA ALONE THAT IS READILY AVAILABLE OVER THE ENTIRE GLOBE. Station pairs disguise the actual temperature, by suggesting in flawed studies that there is little UHI effect, try London 9 degree C difference and every other major cities and towns on the planet. Google population growth and the UHI effect, 9 degrees C is NOT high.
129365. rob at 10:44 AM on 18 November 2008
        It's Urban Heat Island effect
        Chris says, One only needs to inspect the global surface temperature anomaly image with a reasonably informed understanding of human population geography to see that the urban heat effects can't have made significant contribution to global surface warming... Well err Chris, oceans cover about 73% of the planet, not many weather stations there, I believe the desserts cover another 10%, not many there either. The majority of the weather stations were and still are situated in the northern hemisphere and this is exactly where most of the cities are located. Google UHI and population growth and see what you get. The other point Chris is that rural sites show little or no warming. Ask yourself why on earth Hanson/giss would want to compare pristine rural data with dodgy urban sites then use iffy and secret algorithms to try to extract the UHI effect out of the urban data when they have the rural pristine data in the first place, odd that. Also ask yourself why T min is increasing at double the rate of T max, I don`t believe the sun shines at night. Have an honest debate, visit climate audit and wattsupwiththat you lean something to your advantage.
129366. chris at 07:25 AM on 18 November 2008
        It's the sun
        Re #215 A scientist can call himself all sorts of things. Spencer is listed under "Staff" at the Earth System Science Center at the University of Alabama at Huntsville. He may consider himself to be a Meteorologist or a Climatologist, and no doubt an Atmospheric Physicist and so on...it doesn't really matter....scientists consider all sorts of different labels to be appropriate to their jobs/expertise. The salient point is that he's made a dreadful hash of analyzing the satellite MSU data for a very long period indeed, his "efforts" have had to be consistently corrected in the scientific literature, and he has taken to bypassing the normal scientific channels and engaged in attempting to sell nonsense to the general public via dodgy websites and suchlike! I've had a look at the paper you've linked to...if I have time I'll make some comments on the PDO thread where you posted the link....
129367. chris at 06:53 AM on 18 November 2008
        It's the sun
        Re #216 ONE: CO2/temperature correlations: I don't think that's correct WA. The paleorecord shows a rather good correspondence between paleoproxies for cold/warm periods and paleoproxies for low/high CO2. Which particular study/geological period were you thinking of? This subject has recently been very comprehensively reviewed by Royer, and a great slew of data highlights the strong relationship between paleoCO2 and paleo temp (high CO2 corresponds to warm periods and vice versa) right throughout the Phanerozoic (last 460-ish million years). I've reproduced citations to a number of these studies at the bottom of the post. Here's Royer's compilation: D.L. Royer (2006) "CO2-forced climate thresholds during the Phanerozoic" Geochim. Cosmochim. Acta 70, 5665-5675. TWO: CO2/temp relationships during ice age cycles. I'm surprised people are still confused by this very straightforward topic. John Cook has explained this very concisely here: http://www.skepticalscience.com/co2-lags-temperature.htm In a nutshell: CO2 is a greenhouse gas. Raising its atmospheric concentration results in enhanced warming of the Earth, all else being equal. A large amount of scientific data, indicates that the Earth's surface temperature responds to enhanced [CO2] with somewhere around 3 oC of warming (+/- a bit) per doubling of atmospheric CO2: http://www.skepticalscience.com/climate-sensitivity.htm It doesn't matter what caused/causes the enhanced CO2; raising [CO2] results in enhanced greenhouse warming. Compare the ice age glacial/interglacial transitions, and the current global warming: a.) ice-age transitions: Over a period of around 5000 years (around 15,000 to 10,000 years ago), predictable changes in the Earth's orbital properties changed the insolation pattern resulting in a very slow warming, and the earth transited from a glacial to the interglacial period that we now inhabit. Over a period of 5000 years the Earth warmed by around 6 oC overall, and during this period atmospheric CO2 levels rose by 90-100 ppm (from 180-270ish ppm) due probably to very, very slow temperature dependent efflux from warming oceans. The temperature rose around 0.1 oC per 100 years on average, with around 2 ppm of raised [CO2] per 100 years. The raised CO2 lagged the warming initially, but it contributed overall to the net warming, since raised CO2 "traps" more solar energy. b. current global warming: At present the Earth is warming at 0.18-0.2 oC per decade (around 18-20 times faster than during the glacial to interglacial), in response to [CO2] that is rising by around 2.5 ppm PER YEAR (more than 100 times faster than during the glacial to interglacial transition). In each case the enhanced [CO2] results in warming. During the ice age cycles, CO2 rose extremely slowly in response to slow Milankovitch-induce warming, and produced a feedback amplification of the initial warming. Now the CO2 is being released directly into the atmosphere in copious amounts at a massive rate. It doesn't matter how the [CO2] gets into the atmosphere...the Earth warms as a result. CO2 is a greenhouse gas. THREE: Satellite record: The satellite record is pretty much consistent with expectations based on our understanding of the greenhouse effect. Unfortunately the record is not very well constrained (it's also very short...since 1979 only). Roy Spencer has made a dreadful hash of "analyzing" the record over a period of nearly 20 years, but others have corrected a number of dreadful blunders, and there doesn't seem to be any substantive disagreement between the record and the expectations from surface warming combined with our understanding of atmospheric physics and thermodynamics. Which papers were you thinking of that "suggest the "fingerprint" is wrong"? FOUR: warming at night..at the poles...in the stratosphere. Which models are you thinking of specifically? It was prediced as long ago as the early 1980's, that warming in response to enhanced greenhouse gases should be most dramatic in the high Northern latitudes and that the Antarctic would remain "buffered" from the effects of enhanced greenhouse gases for some time. That's certainly turned out to be true. I'm not sure about the day/night expectations, although it seems reasonable that greenhose warming would certainly be effective at night. What's your evidence for a disagrement if you considerone exists? I'm skeptical about your point about the "stratosphere"! Evidence please. I wonder if you meant "troposphere"... ----------------------------------------------------- In relation to point ONE above, more recent studies supplement the information in Royers compilation and cover additional periods with new data sets right through the past several hundreds of millions of years: R.E. Carne, J.M. Eiler, J. Veizer et al (2007) "Coupling of surface temperatures and atmospheric CO2 concentrations during the Palaeozoic era" Nature 449, 198-202 W. M. Kurschner et al (2008) “The impact of Miocene atmospheric carbon dioxide fluctuations on climate and the evolution of the terrestrial ecosystem” Proc. Natl. Acad. Sci. USA 105, 499-453. D. L. Royer (2008) “Linkages between CO2, climate, and evolution in deep time” Proc. Natl Acad. Sci. USA 105, 407-408 Zachos JC (2008) “An early Cenozoic perspective on greenhouse warming and carbon-cycle dynamics” Nature 451, 279-283. Doney SC et al (2007) “Carbon and climate system coupling on timescales from the Precambrian to the Anthropocene” Ann. Rev. Environ. Resources 32, 31-66. Horton DE et al (2007) “Orbital and CO2 forcing of late Paleozoic continental ice sheets” Geophys. Res. Lett. L19708 (Oct. 11 2007). B. J. Fletcher et al. (2008) “Atmospheric carbon dioxide linked with Mesozoic and early Cenozoic climate change” Nature Geoscience 1, 43-48.
129368. Wondering Aloud at 05:57 AM on 18 November 2008
        It's the sun
        172 chris The paleo record shows high CO2 during cold eras low CO2 during warm periods, in short No connection. Even the record that is supposedly the great proof of the concept, from ice cores clearly shows that for the recent past temperatures rise first followed by CO2 increasing. Which is simple to explain with equilibrium chemistry. This is what I was referring to by the paleo record not supporting CO2 as a primary driver. John may well be right and there is some delay mechanism followed by CO2 increasing the warming but this is, if true, at most secondary in the paleo record. As to the satellite record and warming of your later comment, there is much discussion of what the supposed pattern of that warming should be. I am not familiar enough with your cited paper to know what it finds but as others have pointed out above there are a number of papers that suggest the "fingerprint" is wrong. In the past we have handled this by changing what we think the fingerprint should be, correctly or incorrectly I don't know. Remember when models showed the warming would occur first and most dramtically at night and at the poles and that it would be greater in the stratosphere? Two examples of "definite fingerprints" of AGW that made great sense but, didn't work out?
129369. Mizimi at 05:01 AM on 18 November 2008
        It's Urban Heat Island effect
        A passing thought...what data set is the temp anomoly based on? Is it raw data or the data compiled AFTER removing UHI effects? Be nice to know..........
129370. Quietman at 03:44 AM on 18 November 2008
        It's the sun
        chris According to spencer he is a meteorologist. I posted a link to his latest article in the PDO thread.
129371. Patrick 027 at 16:03 PM on 17 November 2008
        Arctic sea ice melt - natural or man-made?
        Clarification: Conservation of (Angular) momentum. It may have seemed a bit abstract, even if well reasoned, to assert conservation of angular momentum in the absence of torque and use this principle to guide understanding of fluid motions, and additionally to include planetary vorticity. Point 1. Illustration of the link between angular momentum and linear momentum. Suppose two balls are rolling past each other as if on different parallel tracks. Picking an inertial (non-acceleration - this also means not rotating) reference frame that follows the center of mass of the system of balls. Thus, it can be seen that both balls are either approaching the origin and each other, or moving away from the origin and also each other. Add a force on each ball such that there is no torque on the system of balls. For just two balls (or any combination of two groups that make up the whole), this requires the 'line of action' of the force acting on both pass through the center of mass. If there is a net force on the system, the center of mass of the whole system accelerates, but provided there is no torque on the system, a system-centered reference frame can be allowed to accelerate such that there is no net apparent force. In that case the sum of all forces is zero - for just two balls, it is as if the balls either repel or attract each other with equal and opposite forces. The angular momentum is the equal to the cross product of the position vector times the mass times the velocity vector for each ball, where the position vector is from the origin (the center of mass of the two balls) - a vector that points from (0,0,0) to the ball. Notice that for two balls on parallel paths, this is equal to the cross product of the shortest vector from one path to the other times the linear momentum of the ball on the second path (it doesn't matter which path and which ball - the two vectors between paths are equal and opposite, as are (in the given reference frame) the two linear momenta. If the balls are rolling towards each other and they are then pulled toward each other, they accelerate, so that they gain some velocity in rolling toward each other in the direction they were going while at the same time they change directions (the component of acceleration perpendicular to velocity) so that (after any given length of time) they now roll faster towards each other on different paths that are closer together. The physics works out such that the distance between paths and momentum along them are inversely proportional, thus keeping the angular momentum constant. On the other hand, if an attractive force between the balls is applied after their closest approach, so that they are moving away from each other, then initially the paths will move farther apart while the motion slows down; the two changes again are inversely proportional. And so on for repulsion. For balls moving along a circle, forces on the balls toward or away from the center of the circle will cause spiralling in or out - but steady circular motion is itself acceleration toward the center; thus pulling toward the center causes increased speed while shrinking the radius; pushing out slows down speed while enlarging the radius, etc. And on a rotating planet? 1. First, you may have wondered - why not just conserve the total angular momentum - as a vector quantity - while moving about? For example, planetary vorticity and thus the planetary angular momentum as vectors are parallel to the Earth's axis (and point North - 'right hand rule'); in the former discussion what was often mentioned was the local vertical component of those things. While in general the vertical component of a torque vector (acting on the angular momentum of horizontal motion) is relatively small for larger-scale motions, torques with other components can be important. If rotating air, including it's rotation aquired from the rotating Earth beneath it, is carried to some other latitude, a gyroscopic effect would tend to keep it oriented as it was, rather then bending with the curve of the Earth. (There are actually vertical accelerations associated with the coriolis effect.) Two vertical forces are very strong - gravity and the counterbalancing vertical pressure gradient force are just about equal, and they dominant well above everything else, except for some smaller-scale forces such as rapid updrafts in strong thunderstorms whose accelerations balance an otherwise imbalance in vertical forces - anyway, these vertical forces easily keep the air lying flat or on isentropic or other surfaces whose slopes are determined mainly by other processes. The local vertical component of the absolute (relative + planetary) angular momentum vector can thus be conserved (absent other torques) even as the direction of vertical changes going around the Earth. 2. The conservation of angular momentum associated with planetary vorticity f can be illustrated as follows: if there is a ring of air and that ring is then brought in toward it's center (convergence) - note that except for a beta effect (df/dy not equal to 0), the geostrophic wind is non-divergent in isobaric (and also isentropic, I believe) coordinates - the convergent motion may be ageostrophic, and if so, the coriolis force on it is not balanced by the pressure gradient force. This means the coriolis force itself exerts a torque about a center on ageostrophic motions that are toward or away from that center, thus changing the relative angular momentum - but conserving the absolute (relative + planetary) angular momentum. (This torque is not typically labelled as a torque in equations because the vorticity equations are written with the sum of f and RV. If it is to be regarded as a torque, it is an important torque; otherwise there are not generally any such important torques acting on large scale quasi-horizontal motions (except friction near the surface)). Specifically, the coriolis acceleration's magnitude = f*u, where u is wind speed. Acceleration over time produces a change in velocity; wind speed u over time produces a displacement. Thus an 'ageostrophic displacement' produces a a change in velocity proportional to the displacement times f. Which brings us to 'absolute momentum'...
129372. Quietman at 05:36 AM on 17 November 2008
        It's Pacific Decadal Oscillation
        Roy Spencer's view on how the PDO fits the equation:, a brief part of a new paper being submitted.
129373. chris at 12:37 PM on 16 November 2008
        It's the sun
        Re #212, On Spencer and "political beliefs"... Well yes, Mizimi, I suspect that your apparent missunderstanding of the nature of science in relation to religion and politics is a contrived one (played out for comedy effect?....or maybe you just like reading my posts!). I'm sure you know really that science is all about the evidence, and that's the essential difference between science and religion or political advocacy. So one would only pursue the deceit that CO2 all of a sudden has stopped being a greenhouse gas (or that the massively raised levels of atmospheric CO2 were from volcanoes), for example, if one was attempting to make some sort of political (or other agenda-led) capital. Wouldn't you say so? The similarities between global warming denialism and modern-style "creationism" are interesting, and Spencer provides an example of how these can induce a perversion of scientific evidence in support of an agenda. In the US these stances have a tendency to coincide, such that it's quite common for those that wilfully choose to ignore or misrepresent the scientific evidence for evolution (e.g. "hard core" neo-"Christian" chaps!) are also likely to participate in misrepresenting the science on global warming. I find it particularly fascinating that someone who's career as a staff scientist involved "measuring" tropospheric temperatures would drift down this route, but there seems to be a particularly attractive (for some people) political position in the US that induces this anti-rational behaviour...and which incidentally is catnip for those with really serious anti-science efforts to pursue (e.g. pretending that smoking isn't a strong contributory factor in lung cancer and respiratory and circulatory disease..or that aspirin taking in children doesn't enhance their likelihood of contracting Reyes syndrome...that sort of thing!).
129374. chris at 12:26 PM on 16 November 2008
        Evaporating the water vapor argument
        Very funny Mizimi I particularly liked the "White staffer" Lew Moninsky! (The Greenpeace "spkesperson Rainbow Treetower is a bit obvious...)
129375. chris at 11:29 AM on 16 November 2008
        It's the sun
        Question 1: Very little CO2 has been added to seawater by "undersea" volcanic activity. We know this from (at last) two sources. (i) If undersea volcanic activity resulted in significant acumulation of CO2 in the oceans, then we should see (have seen) some of this released into the atmosphere. However we have atmospheric CO2 records going back millions of years. One would have to make the rather specious "argument" that undersea volcanic activity has all of a sudden, after millions of years, started releasing large amounts of CO2 just when mankind has stared releasing vast amounts of CO2. However there's no real world evidence for enhanced undersea volcanic activity, let alone enhanced production of CO2 from volcanic activity. And we know anyway [see posts #201/208 and (ii) just below] that the massive amounts of CO2 in the atmosphere that is partitioning in massive amounts into the oceans is from fossil fuels. (ii) As already described, tectonic activity in general results in release of very small amounts of CO2 {less than 1% of current anthropogenic levels) and this is largely from non-organic sources. Undersea volcanic activity is by definition undersea (!), and the sources of undersea volcanic activity are at sites of nascent plate boundaries (e.g. Mid Atlantic ridge) or mantle plumes (e.g. under Hawaii). Any CO2 released from these sources have pretty normal 13C/12C compositions (around 1% 13C) since the carbon is almost exclusively from non-organic sources. In fact it may be more likely that CO2 from land volcanoes (at subduction zones on continental margins) will have a little CO2 from organic sources since these will release some CO2 from carbon previously subducted from the ocean floor, a bit of which might be organic ('though not much, since organic material in the ocean finds itself utilised within the food chain...). But in general volcanos (either undersea or on land) release rather small amounts of CO2, and the carbon isn't particularly 13C-depeleted. and so on...there more evidence from proxy measures of sea-water pH and such like... Question 2: The amount of 13C from nuclear tests/accidents is tiny in proportion to the amount of natural 13C in the environment. 13C comprises around 1% of carbon (it's naturally abundant at around 1%). The contribution from non-natural sources is immeasurably small. The situation is a bit different for 14C. Remember that 13C is a stable isotope of carbon whereas 14C is an unstable radioactive isotope, which additionally has a very short half-life (6000-ish years). The fact that there is any appreciable amount of 14C in the environment at all, is that this is being continually produced in tiny, tiny amounts by the action of gamma rays in the upper atmosphere. So the contribution from mid-20th century nuclear testing is significant, and there is a bit of a "spike" in the atmospheric 14C record...
129376. chris at 11:27 AM on 16 November 2008
        Water vapor is the most powerful greenhouse gas
        Source please Mizimi for those columns of faux-"numerology". Where did you cut and paste them from and what do the columns mean?
129377. Mizimi at 09:18 AM on 16 November 2008
        It's Urban Heat Island effect
        PS: another thermal image site for Paris, France: http://www.geo.uni.lodz.pl/~icuc5/text/O_27A_2.pdf
129378. Mizimi at 09:11 AM on 16 November 2008
        It's Urban Heat Island effect
        Have alook at http://www.seedgen.com/thermallondon/space.htm#space "LONDON FROM SPACE Adapted from material kindly submitted by the The British National Space Centre on behalf of the Science and Technology Facilities Council London and many other English cities can be seen as bright thermal `footprints' in this night-time image of England, France and the English Channel. In the false-colour representation used here, temperature increases through blue and yellow to orange over a temperature range of 278-288K (= 5 to 15 degrees Celcius). London Airport reservoirs appear as orange hot spots as they remain hotter than the surrounding land that has cooled quicker since the sun has gone down; the water bodies have a higher thermal inertia than the land due to the higher specific heat capacity. The image was from captured by the European Space Agency's (ESA) ERS-1 satellite at an altitude of around 777 km. (This is a 12 micron night-time image acquired on 7th September 1991; the area covered is 512 x 512 square km.)" Note the temperature range...10C Also , on the same web site you can see THERMAL images of the UK which clearly show the higher temps around cities.
129379. Mizimi at 09:00 AM on 16 November 2008
        It's the sun
        Question: My understanding is that most 'volcanic' activity is undersea and that the CO2 thus produced would go more or less immediately into solution? In which case how can one quantify how much is being added...? Question: How much C13 has been produced by nuclear tests and accidents? And what effect has it had on the general level of C13 in atmospheric CO2 ? "Unfortunately Spencers "style" of ceationism ..... is really a political position." Well, given the minimilistic numbers on A CO2 contribution to 'global warming' one could well say the same of adherents to that belief.
129380. Mizimi at 08:10 AM on 16 November 2008
        Water vapor is the most powerful greenhouse gas
        some sums.............contribution to greenhouse effect: 'natural' 'man added' WV 94.999% 0.001% CO2 3.502% 0.117% CH4 0.294% 0.066% NO2 0.903% 0.047% rest 0.025% 0.047% So A.CO2 contributes around 0.117% of total greenhouse effect.....33 x 0.117% = .038 degC Total A GG's contribute around 0.28%...33 x 0.28% = 0.09 degC
129381. Mizimi at 07:49 AM on 16 November 2008
        It's cosmic rays
        It is suggested that high level cloud formation is not affected because of the differences between ice crystals (high level)and vapour ( low level). There is a strong correlation between CR's and low level cloud referred to in this paper... http://www.solarstorms.org/CloudCover.html cosmic ray/low cloud cover. "The correlation of low cloud factor and cosmic ray flux is unexpected as the maximum degree of ionization by cosmic rays occurs in the altitude range 12-15km, i.e. close to or above the tropopause. The altitude ranges covered by clouds of different type are: 0-3.2 km for the low clouds, 3.2-6.5 km for the mid-level clouds and 6.5-16 km for the high clouds. Thus any cosmic ray induced cloud effect would be expected to be stronger for high rather than low cloud layers (Kernthaler et al. 1999; Jorgensen and Hansen, 2000). An explanation may lie in the fact that, as the neutron detectors are located at ground level, the measured flux is more representative of lower than higher regions of the atmosphere. Also, we suspect that the physical state of the cloud droplets may play a significant role in the cosmic ray-cloud interaction. It has been pointed out before that the physics of ice and liquid clouds may differ (Gierens and Ponater, 1999). By analysing different low cloud types separately we found that clouds in a liquid phase account for almost all the variability during the observed period, leaving the ice clouds constant in time, except at the poles where a slight increasing trend for some of the ice cloud types is found. Thus the greater sensitivity of low cloud to cosmic rays may result from the preponderance of liquid phase cloud types at lower altitudes (less than 6-7 km). "
129382. Mizimi at 07:40 AM on 16 November 2008
        Evaporating the water vapor argument
        "(Washington, DC) The Environmental Protection Agency is seeking to classify water vapor as a pollutant, due to its central role in global warming. Because water vapor is the dominant greenhouse gas in the atmosphere, accounting for at least 90% of the Earth's natural greenhouse effect, its emission during many human activities, such as the burning of fuels, is coming under increasing scrutiny by federal regulators. Until now, the carbon dioxide produced during the burning of fuels has been the main concern. The extra carbon dioxide causes a manmade enhancement of the greenhouse effect. But water vapor is also produced by combustion of most fuels, as well as by industry and utilities that use water for cooling. The EPA would be able to regulate its manmade sources if it is classified as a pollutant. EPA Director of the Department of Pollutant Decrees, Ray Donaldson, said, "Back before carbon dioxide was dangerous, we simply assumed that water vapor was also benign. But all reputable scientists now agree that the increased water vapor content of the atmosphere from such sources as burning of fuels and power plant cooling towers will also enhance the greenhouse effect, leading to potentially catastrophic warming." http://www.ecoenquirer.com/EPA-water-vapor.htm see post #16
129383. Philippe Chantreau at 13:37 PM on 15 November 2008
        Arctic sea ice melt - natural or man-made?
        Beck is no "professor." What are his publications? (Energy and Environment does not count)
129384. chris at 11:18 AM on 15 November 2008
        Models are unreliable
        Oh dear. You're attempting to sell the unsubstantiated deceit that climate scientists don't understand feedbacks in relation to the earth's energy budget, and thus you can make a blanket dismissal of everything I present or every reference I cite. That's an excellent wheeze..you're entranced by the conceit that you are right and everyone else is wrong! Sadly, so far it's been easy to show that it is you that has glaring misconceptions on the science. Let's look at the essential errors in your post #67: 1. I pointed out that the UAH satellite data is rather dodgy, bedevilled as it is by a slew of errors yielding artefactual cooling trends (see references cited in post #66). The RSS data set is likely to be rather more accurate. Not very controversial I think. 2. I also pointed out that the tropospheric temperature measures are not particularly robust (they are broadly consistent with the land-sea surface record, but are not particularly well-constrained), and that while efforts are made to improve these, particularly in relation to calibrations, and taking account the relatively short time series (satellite measurements of tropospheric temperatures are available only from 1979), it makes more sense to consider the land-sea surface temperature measures if one wants to establish how our world is responding to enhanced greenhouse gas forcing (see references cited in post #66). Not very controversial either. 3. These (NASA GISS, Hadcrut, NOAA) show long warming trends from the mid 1970's through to the present. 4. You are choosing to make an analysis in which part of the land-sea surface 2008 data (the first 9 months) is compared to the 2000-2007 mean. But it doesn't make any sense in the context of greenhouse-forced warming trends, to compare single years (or parts of year) with anything. This should be obvious. Here’s why: 5. The land-sea surface records show a warming trend somewhere near 0.18-0.2 oC per decade over the last 30-ish years. Obviously, since year on year variations can result in short term drops or rises in the surface temperature by 0.1 oC (or even 0.2 oC if one considers the effects of the extraordinary El Nino year, 1998), one needs to consider trends over longish periods - looking at parts of single years is highly misleading, since there is rather a lot of “noise” on the temperature record. 6. Let's look for example at your cherrypicked early-mid 2008. The first 5-6 months of 2008 were strongly influenced by a La Nina episode that suppressed the surface temperature measurably. In addition the sun has reached the very bottom in its 11 year solar cycle and will only start to significantly supplement greenhouse warming in a couple of years. So we've had a short period when "cooling" phenomena have coincided. That's measured in the surface (and tropospheric) temperature records. Not a big surprise. 7. But of course if we're interested in how the Earth's surface temperature responds to enhanced greenhouse warming, we don't play at contrived wonderment that the surface temperature has cooled a bit due to fluctuations that happen to be in a cooling direction for several months. In another years or two the rise in the solar cycle will be supplementing the greenhouse enhanced forcing rather than opposing it as in the last few years. No doubt we’ll get the next record year at the next significant El Nino or two… Here's the other problems in your post: 1. Oddly, while you attempt to make an "argument" on the basis of a short 9 month period, you then proceed to attempt a completely contrary “argument” around the notion; [Dan Pangbourn: "But understanding global climate does not come from examining a period so brief as the last decade, or even the last century"]. A lovely cherrypicking of 9 months of data is fine though! The other problem with the "argument" that you attempt to develop from that, is that no-one has ignored the temperature changes during the past 1000 years. There's a reasonably good understanding of those (hint - it's the sun and volcanic activity that has resulted in small and slow changes in the earth's surface temperature during those periods). Note that the Earth's surface temperature "recovered" from the Little Ice Age by around the middle of the 19th century. I wonder whether you are trying to pretend that 20th century and contemporary warming is "recovery" from the LIA! 2. Be aware that the only predictors of significant Anthropogenic Global Warming are certainly NOT Global Climate Models or GCMs. What an odd notion to try to insinuate; what evidence lends to you consider such an ill-informed idea? The major predictor of Anthropogenic Global Warming is our understanding of the Earth's greenhouse effect and the physics/thermodynamics of the response of the earth's energy budget to enhanced greenhouse forcing. That's why (to give one of dozens of examples going pack to the mid 19th century), Wallace Broecker was able to predict in 1975 that the Earth’s global temperature would likely be warmer by the early 2000’s than at any period in the previous 1000 years. The evidence indicates he was right. [[b][/i]Broecker, WS (1975) “Climate Change: Are we on the brink of a pronounced global warming ? Science 189, 460-463[/i][/b]] Broecker didn’t have a GCM at hand (and nether did John Tyndall in the mid 19th century nor Arrhenius in the late 19th century and so on, each of whom understood that atmospheric CO2 contributed to the Earth’s enhanced temperature above its “black body” temperature and the effects of enhancing greenhouse gas forcings). You seem to have a severe misconception of the scope of GCM’s and their use in relation to understanding the evolution of the climate in a warming world, its spatial distribution and consequent effects (rainfall patterns, heat transfer by air and ocean currents and so on). So let’s not pretend that anthropogenic global warming arises magically from climate models. We’ve known about global warming in response to anthropogenic enhancement of the earth’s greenhouse effect for over 100 years. 3. There isn’t any data from the Vostok core that indicates “its been warmer than now at other times during the Holocene”. Unless by “it” you mean Vostok. One location does not a global temperature make. 4. It does seem to have been a tad warmer during the last interglacial period particularly around 130,000 to 125,000-ish years ago. Unfortunately sea levels were around 4 metres higher then than now as a result. That’s one of the many reasons we don’t want to push temperatures up much further. 5. What “quiet sun”? The present minimum which is opposing enhanced greenhouse-induced warming will in a year or two begin to “supplement” this. Getting excited about the low point in the rather regular 11 year sinusoidal variation in the solar output is nonsense. And your repeated misconception about feedbacks: 6. Despite agreeing that enhanced CO2 results in enhanced greenhouse forcing with resultant atmospheric warming that yields a water vapour feedback, and the abundant evidence that the Earth responds to enhanced atmospheric CO2 concentrations with a warming encompassing a net positive feedback that yields a surface temperature near 3 oC, you still assert with zero substantiation that net positive feedbacks don’t exist. I wonder when you’re going to provide any evidence in support of that assertion other than “I know I’m right and everyone else is wong”! I explained some of the essential features of feedbacks in post #64. Your response was to parrot your mantra (paraphrasing) “I’m right and everyone else is wrong”. Some argument!.....
129385. Dan Pangburn at 07:30 AM on 15 November 2008
        Models are unreliable
        The discovery that the Climate Science Community is uninformed on Dynamic System Theory and the ramifications thereof were presented at post 61. Their lack of understanding of Dynamic System Theory prevents them from recognizing that some important aspects of earth’s climate are easily determined; specifically that the imposition of significant net positive feedback in their GCMs is a mistake (other deficiencies regarding GCM use are listed at post 32). All of Chris’ comments and references should be considered in the context that they are uninformed in a relevant part of science and that they are unaware that they are uninformed. Chris presented an extensive diatribe (including several references) denigrating the UAH reporting of lower atmospheric temperature anomalies that were based on measurements made by satellite. The diatribe includes comments such as “incompetent disregard”, “UAH is a dodgy source” and “scandalous record”. Then Chris writes “The RSS tropospheric data is likely to be more robust.” The reader is invited to look at the RSS data set. It can be seen at http://www.ncdc.noaa.gov/oa/climate/research/rss_monthly_msu_amsu_channel_tlt_anomalies_land_and_ocean.txt . Doing the same analysis on the RSS data as was done on the UAH data shows that the AVERAGE GLOBAL TEMPERATURE for the first 9 months of 2008 is LOWER than the average from 2000 thru 2007 by an amount equal to 39.8% of the total linearized increase (NOAA temperature anomaly data) during the 20th century. Thus the RSS data corroborate the UAH data. It will be interesting to see what fault Chris now finds with the RSS data. Both the UAH and RSS data sets use satellite information which measures lower atmospheric temperature. The atmosphere has low thermal capacitance (ability to store heat) so it changes temperature comparatively quickly. The other sources: Hadley, http://www.cru.uea.ac.uk/cru/data/temperature/hadcrut3gl.txt, GISS, http://data.giss.nasa.gov/gistemp/tabledata/GLB.Ts+dSST.txt and NOAA, ftp://ftp.ncdc.noaa.gov/pub/data/anomalies/monthly.land_and_ocean.90S.90N.df_1901-2000mean.dat , report land, ocean and combined land-ocean measurements. The land-ocean measurements are weighted to account for the fact that there is much more ocean area than land area (and other factors) and are presented as average global temperature. Applying the same method to the global average surface temperatures (latest available) as was done for the atmospheric temperature results in (there is less decline because of the influence of higher thermal capacitance) 21.8% (9 mo), 20.0% (10 mo) and 14.4% (9 mo) for Hadley, GISS and NOAA respectively. Thus all agencies are consistent in reporting the recent temperature decline. But understanding global climate does not come from examining a period so brief as the last decade, or even the last century. Any assessment of climate change that limits itself to a period that is a recovery from the LIA (Little Ice Age) while ignoring the decline in temperature that occurred during the change from the Medieval Warm Period (aka Medieval Climate Optimum) to the LIA is at best incomplete. Be aware that the ONLY predictors of significant Anthropogenic Global Warming are Global Climate Models (aka General Circulation Models) or GCMs. The only existing exact, correct computer of global climate is the planet itself. One of the outputs of this computer is recorded as temperature history. Temperature history, to those with even a minimum understanding of Dynamic System Theory, proves that net positive feedback does not occur in global climate. Without significant net positive feedback the GCMs do not predict significant global warming. Chris talks about glacier shortening but ignores that the glaciers started shortening about a century BEFORE the beginning of increase of substantial fossil fuel use and continued to shorten at the same rate with absolutely no indication of any influence from increased atmospheric carbon dioxide. This contributes to the growing realization that the GCM based predictions are faulty. Incidentally, imagine what was happening to glacier length during the period from the Medieval Climate Optimum (that Mann tried to claim never happened) until the lowest temperatures of the Little Ice Age. No one can be sure where the average global temperature will go from here. According to Vostok ice core and other data it has been warmer than now at other times during the Holocene (the last 11,000 or so years) and other interglacial periods so eventual temporary further rise is not out of the question. However, the change in pattern since 2001, the recent downtrend, and continued quiet sun are all indicating that the planet is in for a continuation of the cooling trend. The huge thermal capacitance of the oceans will cause the cooling to be gradual, as was the warming. The real issue is not the climate. There is no objective evidence that human activity has ever had or ever will have any significant effect on it. The real issue is the damage to human freedom and prosperity that can happen because of a few government financed alarmists and their followers who are unaware of a relevant part of science. Record low temperatures and newsworthy rare or early snow falls are starting to get attention. Unfortunately, it may require a drastic decline of temperature with accompanying crop failure and wide spread starvation for many to begin to realize that they may be missing something.
129386. chris at 05:28 AM on 15 November 2008
        It's the sun
        Re #192 and #203 On Roy Spencer: Roy Spencer has spent the better part of his "scientific" career as a staff scientist engaged in analysis of satellite Microwave Sounding Unit (MSU) data on tropospheric temperatures. This has been carried out for 15 or more years with a combination of incompetence (that borders on the fraudulent), and widescale propagandising for false interpretations outside of the normal channels of scientific communication. In recent times he's attempted to pull the wool over the eyes of the gullible and similarly misguided with a contrived mishmash of a notion relating to supposed natural internal variations in the climate system as a cause of 20th century global warming. The fact that Spencer is a creationist doesn't necessarily add or subtract to the fact that he's done disgracefully incompetent science for years, and that he attempts to "sell" falsehoods direct to the public through websites and the resources of anti-democratic organizations. After all there are a great many first-class scientisits that have strong religious beliefs. Unfortunately Spencers "style" of ceationism isn't really a religious belief...that class of "pseudo-Christian" fundamentalist "creationism" (wrapped up in the "intelligent design" "package") is really a political position. Sadly, it's very much in keeping with Spencer's apparent willingness to subvert scientific honesty in the service of creepy ideologies. My personal view is that Spencer is rather taken with the modern "pseudo-Christian" creationinist success in hiving of quite a large "rump" of the poorly educated, misguided and various assorted bullies, with what is obviously complete nonsense, and quite likes the fact that much of that same great "unwashed" are more than happy to swallow his anti-science nonsense on climate-related matters. As always in science it's about the evidence. Spencer has spent nearly 20 years making a complete hash of this, and that's why bone fide scientists and well-informed policymakes are less than thrilled with his "contribution"...
129387. chris at 23:03 PM on 14 November 2008
        Evaporating the water vapor argument
        Well yes, it's all about the evidence Mizimi, and not about trying to trap perceived "opponents" with semantic games! So it's pretty uncontroversial that enhanced atmospheric CO2 results in enhanced water vapour (this can be measured in the real world) as a feedback to CO2-induced warming. A warmer atmosphere promotes the enhanced atmospheric partitioning of water vapour. We can call this WV feedback AWV since it's an indirect a consequence of our CO2 emissions. However the effect of spraying water/water vapour into the lower atmosphere (from cooling towers and such like) has a minimal net contribution to greenhouse-induced warming, since this excess just comes straight out of the atmosphere within a very short period afterwards... So one needs to be clear about what "AWV" one (or two in this case!) is (are) talking about!
129388. Arkadiusz Semczyszak at 18:44 PM on 14 November 2008
        Arctic sea ice melt - natural or man-made?
        I’m come back to the subject - matter, precise “Arctic ice melt…” “natural or man-made…” I think: “fifty/fifty”… In the meeting AGU (XII 2007) the Scientists in University Cincinnati, Lamont Doherty Earth Observatory and University Maine (T.V. Lowell, M.A. Kelly, B. Hall., C.A. Smith, K. Garhart, S. Travis B.M. Goehring and G.H. Denton) (http://wattsupwiththat.files.wordpress.com/2007/12/uc-agu-greenland-dec-07-v45.pdf) was a demonstrate photography 6-8 cm diameter a fossil tree - from edge ice cover of the dome Istorvet, in Liverpool Land, Scoresby Sund (East Greenland - 70°50’N, 22°13'W) in situ with roots in > 8 cm a organic layer soil…The age by 14C a fossil tree = 1590 (±25) - 1040 (±30) yr BP (~ 400 -1015 AD), with high vegetation for period 840 - 980 AD. The Temperature of Air in cool East Greenland was a sufficient by vegetation of tree and shrubs on ~280 - 600 vertical m above the sea level… Brooks C.E.P., already in 1950 (Climate trough the Ages. Ernest Benn Limited, London. p. 395.) behind: Koch 1945, Petterssen 1914; say: - in period between V-VI - X-XI century, the Arctic Sea was do not have ice cover (…) or was to have firn-snow-semi-ice cover. For example a confirmation it is in: Berge J., Johnsen G., Nilsen F., Gulliksen B., Slagstad D., 2005. Ocean temperature oscillations enable reappearance of blue mussels Mytilus edulis in Svalbard after a 1000 year absence. Marine Ecology Progress Series, 303; 167-175.; and in: Story of Viking Colonies' Icy 'Pompeii' Unfolds From Ancient Greenland Farm - with Science, The New York Times 17.04.2008 - in 1935 the Arctic ice cover was likely as 2007. See “Greenland warming of 1920–1930 and 1995–2005” (GEOPHYSICAL Research Letters, VOL. 33, L11707, doi:10.1029/2006GL026510, 2006 33, L11707, DOI: 10.1029/2006GL026510, 2006) and http://klimat.files.wordpress.com/2007/03/salt_rec.jpg If it is true: what about the polar bears ‘et camarades’, in MVP. - dear IPCC-expert’s ? …and: “natural or man-made…” I remind You, that: “In the past two centuries, the Arctic has warmed about 1.6 degrees. Dirty snow caused 0.5 to 1.5 degrees of warming, or up to 94 percent of the observed change, the scientists determined.” + Solar Activity 14C - data from United States Geological Survey - see: Modern Maximum; and 1% S.A. for the different effects = even +/-2,3oC global temperature - und ours clear… …about professor Beck - historical CO2 - he’s right: Ice core - don’t say true - You must see in this paper: “Phytoplankton Calcification in a High-CO2 World” : M. D. Iglesias-Rodriguez, et al. Science 230, 336-340, 18 Apr 2008. freely downloadable from http://www.sb-roscoff.fr/Phyto/index.php?option=com_docman&task=doc_details&gid=418&Itemid=112,; and “A bi-proxy reconstruction of Fontainebleau (France) growing season temperature from AD 1596 to 2000” (www.clim-past.net/4/91/2008/) Fig. 2b; 3a - δ13C… My friend professor Jaworowski said: Ice core - here is too great chemical relation between H2O and CO2 - ice cores “say” probably only about history a remove CO2… Comparison the papers: “Rapid atmospheric CO2 changes associated with the 8,200-years-B.P.” Wagner et al 2002 (www.pnas.org/content/99/19/12011.full) fig 2. with fig. 3C (C4 %) in “Comparison of multiple proxy records of Holocene environments in Midwestern USA”: Baker et al. 1998, (http://people.ku.edu/~lgonzlez/NewFiles/Publications/Bakeretal98.pdf.) …and see: "A role for atmospheric CO2 in preindustrial climate forcing" by Thomas B. van Hoof et al. http://www.pnas.org/content/early/2008/10/03/0807624105.full.pdf P.S. Sorry by my Slavonic - Polish name and English Language…
129389. Mizimi at 08:12 AM on 14 November 2008
        Evaporating the water vapor argument
        Careful Chris...it looks like you're suggesting AWV might be having some effect after all.....
129390. Patrick 027 at 13:37 PM on 13 November 2008
        Arctic sea ice melt - natural or man-made?
        Actually, with regard to the horizontal scale of vorticity advection (and resulting vertical scale for differential vorticity advection): It's not just that the horizontal scale of temperature variation is affected. 'Before' that step, the pressure changes are also affected, in that the horizontal variation of vorticity advection directly causes horizontal variation in the divergence and thus in the pressure changes, so that there is a changing pressure gradient (or vertical variation of that for differential vorticity advection). A change in the pressure gradient is necessary if the adjustment to near geostrophy has both the geostrophic RV (or vertical variation of that) and actual RV approaching each other. Otherwise, without any horizontal variation in vorticity advection, the divergence could continue until the RV returns to the initial geostrophic RV. Sustained RV changes would be limited to the boundary of such a region. Of course accompanying temperature advection could have some other effect... On the other hand, sinusoidal horizontal variation would allow various changes to remain proportional to each other at each horizontal position.
129391. Patrick 027 at 15:05 PM on 12 November 2008
        Arctic sea ice melt - natural or man-made?
        ...continued... Notice that even if the wind is divergent, the relationship for dv/dx remains intact - that is, the variation along an isotherm of the component of the wind parallel to the temperature gradient - this acts to turn the temperature gradient rather than to change it's magnitude. --- Poleward geostrophic wind is convergent; equatorward geostrophic wind is divergent. If the wind is tending towards geostrophy, this pattern of divergence will change the vorticity, interestingly in the opposite direction that the corresponding planetary vorticity advection changes the relative vorticity (without divergence and friction, etc, AV = f + RV is conserved so changes in f must drive opposite changes in RV). Differential planetary vorticity advection can act as differential RV advection, but is not tied to temperature advection as RV advection is by geostrophic shear as described above (320,321). If planetary vorticity advection occurs through an entire column, then RV is created (or destroyed) over the whole column. The response for equatorward flow is increasing ageostrophic cyclonic RV, which drives divergence, lowering the pressure and the cyclonic AV until the RV and pressure come into balance; specifically the Laplacian of the pressure field has to increase, which corresponds to a relative horizontal maximum in pressure drop somewhere. Vertical compression occurs with the air becoming more stable; the isentropes stay near constant pressure near the 'top' of the column, so the pressure drops at each isentrope below, the most near the surface; this corresponds to adiabatic cooling. Horizontal variation in this cooling decreases the divergence and pressure fall at the surface while increasing it above - this being modified again by stability, if I'm not mistaken. Advection of a column over topography is also interesting; in this case, suppose one is moving a column of air downslope. Without any convergence, the pressure is falling at all levels in the column. Horizontal variation in this downslope motion (due to either the wind or the topography or both) drives convergence toward the larger downslope motions, increasing the pressure and vertically stretching the column. Convergence increases cyclonic AV, thus increasing cyclonic RV if f is not changing. Isentropes and pressure surfaces may rise nearly together near the top of the column but the pressure rises on isentropes near the 'dropping' surface. Hence there is warming near the surface, which, to the degree that it is horizontally varied (modified by stability, again, I think**), reduces the relative pressure rise at the surface, increasing convergence and cyclonic AV and RV near the surface, and having opposite effects above. Variations in downslope flow can initiate cyclogenesis...
129392. Patrick 027 at 13:48 PM on 12 November 2008
        Arctic sea ice melt - natural or man-made?
        continued from 320: If we are following the motion, subtract the velocity vector at the point we are following from the total wind field; the remaining component of the wind varies vertically and horizontally relative to a point we are following but is zero at that point. In x,y,p coordinates: For simplicity of illustration, let the frame of reference move with the point, so that the point of focus is 0,0,0. Let isotherms be aligned parallel to the x axis at 0,0,0; thus the temperature gradient is in the y direction, dT/dy. dT/dx = 0. ---- Let the vertical wind shear be equal to the geostrophic wind shear: Geostrophic zonal wind..... u = -(dF/dy)/f Geostrophic meridional wind v = (dF/dx)/f where F is the geopotential (z*g) of an isobaric surface. (The symbol for geopotential used is a capital greek letter, which is F in a symbol font). (z is the geometric height. In this context, g is given as a positive number and is approximated as constant with height; otherwise F = the integral of dz*g) ---- Vertical derivative of F: (a negative sign is used because p increases downward. -dF/dp = -d(z*g)/dp =~ g * dz/dp ...(the bulk of the mass of the atmosphere is in a thin enough layer that the vertical variation of g is a minor issue) = = g * dz/dm * dm/dp ...(where m is the mass per unit horizontal area) = dz/dm = 1/density = 'specific volume' = R*T/p, where R is the ideal gas constant expressed in terms of mass (which will then be different for different gases). and T is the temperature. ---- Vertical (geostrophic) wind shear: du/dp = -1/f * d(dF/dy)/dp = -1/f * d(dF/dp)/dy = -1/f * d(-R*T/p)/dy = 1/f * R/p * dT/dy ...(in isobaric coordinates, horizontal derivatives of p are zero. Any variations in R or an effective R, such as from very high humidity, can be treated by using 'virtual temperature'; In that case, though, adiabatic temperature changes may be a bit different, I think. This is relatively minor issue for Earthly conditions). Let A = R/(p * f) Thus the zonal vertical shear -du/dp = -A * dT/dy. Similarly, the meridional vertical shear -dv/dp = A * dT/dx The negative sign is used for clarity of visualization, because p decreases with increasing z. -du/dp has the same sign as du/dz. ---- Since dT/dx has been set to zero for initial conditions, -dv/dp = 0. ---- Horizontal wind variations: The change in the wind along isotherms, in the x direction: du/dx dv/dx The change in the wind along the temperature gradient, in the y direction: du/dy dv/dy --------------- In a given infinitisimal unit of time t, the changes are: -------- 1. Changes in thermal gradient and geostrophic shear: Notice that, at least initially (and that is the focus here), variations in u don't alter the temperature gradient because u blows along isotherms. The initial effect: dv/dy acts to change the spacing of isotherms; positive dv/dy decreases the thermal gradient dT/dy, etc. dv/dx acts to change the direction of the thermal gradient, by tilting isotherms in the horizontal, introducing a nonzero dT/dx value. These change the geostrophic vertical wind shear. --- 1a. From dv/dx: change in slope of isotherm dy/dx: dy/dx of isotherm = t*dv/dx resulting change in dT/dx: dT'/dx = initial dT/dy * -dy/dx of isotherm = dT/dy * -dv/dx * t change in geostrophic wind shear: -dv'/dp = A * dT'/dx = A * dT/dy * -dv/dx * t = -A * dT/dy * dv/dx * t --- 1b. From dv/dy: change in temperature gradient dT'/dy is inversely proportional to the change in isothermal spacing in the y direction. dT'/dy is equal to the gradient times the length dy' that the wind dv at y = dy pushes into the interval dy, per unit dy: dT'/dy = dT/dy * dy'/dy = dT/dy * -dv*t/dy dT'/dy = -dT/dy * dv/dy * t change in geostrophic wind shear: -du'/dp = -A * dT'/dy = A * dT/dy * dv/dy * t -------- 2. Changes in the vertical wind shear: The initial geostrophic shear advects the horizontal variations in the wind, differently over a vertical distance, producing some additional vertical wind shear. Notice that, initially, changes in the wind over y (du/dy and dv/dy) do not contribute to changing vertical shear because the geostrophic wind shear is parallel to isotherms; geostrophic -dv/dp is equal to zero. Using the initial geostrophic shear: -du/dp = -A * dT/dy --- 2a. From dv/dx: du/dp brings some wind dv' over to (0,0,dp) from dx' = -t*du thus dv' = -t*du * dv/dx and so the change in wind shear dv'/dp is: dv'/dp = du/dp * -dv/dx * t = -A * dT/dy * dv/dx * t -dv'/dp = A * dT/dy * dv/dx * t --- 2b. From du/dx: du/dp brings some wind du' over to (0,0,dp) from dx' = -t*du thus du' = -t*du * du/dx and so the change in wind shear du'/dp is: du'/dp = du/dp * -du/dx * t = A * dT/dy * -du/dx * t -du'/dp = A * dT/dy * du/dx * t ------------ SO: The changes in geostrophic wind shear by temperature advection: 1a. V'geo = -dv'/dp = -A * dT/dy * dv/dx * t 1b. U'geo = -du'/dp = A * dT/dy * dv/dy * t The changes in the wind shear by vertically-sheared momentum advection: 2a. V'adv = -dv'/dp = A * dT/dy * dv/dx * t 2b. U'adv = -du'/dp = A * dT/dy * du/dx * t ------------- Notice that -V'geo = V'adv, and both are due to dv/dx. The imbalance produced by V'geo is an ageostropic -dv'/dp that is the opposite of V'geo. V'adv is also an ageostrophic -dv'/dp. So both contribute equally to a total ageostrophic -dv'/dp, via the same dv/dx. Notice also that U'geo = U'adv. What does this mean? U'geo is from dv/dy, and U'adv is from du/dx. IF dv/dy = -du/dx, then the relationship between U'geo and U'adv is the same as that between V'geo and V'adv. dv/dy = -du/dx if the wind is non-divergent. THUS, Following the motion, the ageostrophic vertical shear produced by geostrophic vertical shear is twice that due to either the horizontal variation in temperature advection or to the vertically sheared momentum advection GIVEN strictly horizontal flow (x,y,p coordinates) and non-divergent winds; it isn't actually necessary for the total wind to be geostrophic, just the vertical wind shear. It is apparent from this conclusion that horizontal variations in the same mechanism are related; Following the motion, the vertical variation in vorticity advection produces ageostrophic vorticity at the same rate that horizontal variations in temperature advection (specifically, the rate of change of the Laplacian of the temperature following the motion) do. Additional effects can operate indepedently: ageostrophic vertical shear and divergence in the wind (including divergence in the geostrophic wind due to beta; PS the geostrophic wind is non-divergent when beta = 0 for (x,y,p) coordinates and maybe isentropic coordinates (I think**), but not (x,y,z) coordinates), and vertical transport of momentum; advection of planetary vorticity, friction, and diabatic heating/cooling (radiative and latent).
129393. chris at 10:51 AM on 12 November 2008
        Models are unreliable
        I see...a gear switch into tropospherical temperature measures now? Fair enough...however your problems on this issue are similar to those in relation to your cherrypicking of paleotemperature data (see posts #46, 48, 50, 52), your contrived misrepresentation of paleoCO2 data that is completely contradicted by the pukka scientific data (see posts #46, 48, 50, 52, 54), your dull cherrypicking of an incompetent paleotemperature "analysis" in a non-science magazine in which you pretended that the authors own rather fatal correction didn't exist (see posts #54, 58), your confusion over feedbacks…..and Milankovitch contributions (see posts #59, 62, 64)......and so on ..We've pretty much sorted out each of these (see posts #46, 48, 50, 52, 54, 58, 59, 62, 64)....so what about that tropospheric temperature data? There's a pretty serious problem with it I think we would agree. There's no question that the Earth's surface temperature is rising, and has done so rather dramatically since the mid 1970's. We can see this in the surface temperature record..or we can dispense with direct temperature records and construct a temperature record from the record of mountain glacier retreat…it’s pretty uncontroversial that it’s been getting significantly warmer, and rather quickly during the past 30-odd years. Basic atmospheric physics and associated climate models predict a significant tropospheric warming (it should be a bit larger than the surface temperature increase in response to enhanced greenhouse warming). However, the tropospheric temperature record from satellites (Microwave Sounding Units; MSU) and radiosondes (weather balloons) are giving some rather ambiguous data. What’s going on…? Your choice of the UAH record is interesting. The characters that compile this data have pursued a path of studied incompetence during the last 15 or more years, during which their early attempt to sell the notion that the troposphere was actually undergoing a cooling trend, was revised after it was pointed out that (a) their analysis was not sufficiently constrained to distinguish cooling from a warming consistent with physical expectations [ONE], (b) the method of averaging different satellite records introduce a spurious cooling trend [TWO], and (c) their incompetent disregard of orbital decay introduced another spurious cooling trend [THREE]. A little later it was shown (d) that MSU-2 showed a spurious cooling trend due to spillover of stratospheric cooling into the tropospheric temperature signal [FOUR], and later still it was pointed out that (e) the diurnal correction applied by Christy and Spencer (a sad litany of incompetence) was of the wrong sign and gave yet another spurious cooling trend [FIVE]. SO UAH is a rather dodgy source of data unfortunately. It’s a pretty scandalous record in fact. The RSS tropospheric data is likely to be more robust. But, unfortunately, however you look at it, the tropospheric temperature record from satellite measures [the radiosonde record has been shown to be highly contaminated by artefactual biases (see post #60 above)], is still poorly constrained. Despite Christy and Spencers’ assertions of “precision” in these analyses, they seem sadly inaccurate (and more so with Spencer and Christy’s litany of spurious adjustments towards cooling trends which has bedeviled the UAH analyses). Finally even Christy agrees that the tropospheric data worldwide is consistent with expectations from models, although he considers there is still a problem with the tropospherical temperature in the tropics. However that has been resolved recently, and there doesn't seem to be any substantive disagreement between the tropical tropospheric temperature trend as measured by satellites and predicted by models [SIX]. But it’s probably true to say that tropospheric temperature measures cannot really be used to make conclusive conclusions about either the agreement of satellite (or radiosonde) tropospheric temperatures with models or their disagreement. We need better tropospheric temperature measures I suspect. So if we’re really interested in knowing what the Earth’s surface temperature is doing in response to enhanced greenhouse forcing, we can look at the long term surface temperature record (around 100 years longer than the very short satellite tropospheric temperature record), and monitor the effects of warming (enhanced rate of sea level rise; large scale retreat of mountain glaciers; hugely increased rate of attenuation of Arctic sea ice…and so on). We can also note with respect to the troposphere, that the water vapour levels in the troposphere are increasing much as predicted by models [SEVEN], and alternative measures of tropospheric temperature that are not so affected by artifacts (not to mention incompetent mis-analysis; see above) give rather large warming trends (e.g. tropsopheric thermal wind measurements give maximum tropospheric temperature trends of 0.65 +/- 0.47 K per decade [EIGHT]). [ONE] B.J. Gary and S. J. Keihm (1991) Microwave Sounding Units and Global Warming Science 251, 316 (1991) [TWO] J. W. Hurrell & .K E. Trenberth (1997) Spurious trends in satellite MSU temperatures from merging different satellite record. Nature 386, 164 – 167. [THREE] F. J. Wentz and M. Schabel (1998) Effects of orbital decay on satellite-derived lower-tropospheric temperature trends. Nature 394, 661-664 [FOUR] Q. Fu et al. (2004) Contribution of stratospheric cooling to satellite-inferred tropospheric temperature trends Nature 429, 55-58. [FIVE] C. A. Mears and F. J. Wentz (2005) The Effect of Diurnal Correction on Satellite-Derived Lower Tropospheric Temperature, Science 1548-1551. [SIX] B. D. Santer et al. (2008) Consistency of modelled and observed temperature trends in the tropical troposphere. International Journal of Climatology 28, 1703 – 1722. [SEVEN] Soden BJ, et al (2005) The radiative signature of upper tropospheric moistening Science 310, 841-844; Santer BD et al. (2007) Identification of human-induced changes in atmospheric moisture content. Proc. Natl. Acad. Sci. USA 104, 15248-15253; Brogniez H and Pierrehumbert RT (2007) Intercomparison of tropical tropospheric humidity in GCMs with AMSU-B water vapor data. Geophys. Res. Lett. 34, art #L17912; Buehler SA (2008) An upper tropospheric humidity data set from operational satellite microwave data. J. Geophys. Res. 113, art #D14110; Gettelman A and Fu, Q. (2008) Observed and simulated upper-tropospheric water vapor feedback . J. Climate 21, 3282-3289 [EIGHT] R. J. Allen & S. C. Sherwood (2008) Warming maximum in the tropical upper troposphere deduced from thermal winds. Nature Geoscience 1, 399 – 403.
129394. Patrick 027 at 16:12 PM on 11 November 2008
        Arctic sea ice melt - natural or man-made?
        Regarding that last bit: If motion is strictly horizontal, starts out geostrophic and does not accelerate in response to ageostrophy (a completly artificial condition for illustrative purposes), and there is no variation in planetary vorticity f, and diabatic and frictional effects are set aside, and the wind is non-divergent (actually that must be true given geostrophic with no variation in f), then the result is that the wind can drive itself out of geostrophic balance; it does this in two ways that are apparently equal in magnitude according to the math. 1. Horizontal variations in wind velocity can advect temperature in such a way so as to change the horizontal temperature gradient within a layer of air, following the motion. This changes the vertical geostrophic wind shear. 2. The vary same horizontal variation in wind is such that the initial geostrophic wind shear advects those horizontal variations differently over a vertical distance, so that the resulting vertical wind shear through the layer of air, following the motion, is equal and opposite to the change in the geostrophic wind shear from 1. Hence, the resulting ageostrophic vertical shear is twice that of either 1. or 2. by itself. Horizontal variation in 1. can change the Laplacian of the temperature field. Horizontal variation in 2. can correspond to differential vorticity advection.
129395. Patrick 027 at 15:35 PM on 11 November 2008
        Volcanoes emit more CO2 than humans
        "Mystery Wave Strikes Maine Harbor" - interesting, yes. Likely related to climate change, or a multidecadal scale geological variance - the later seems unlikely, the former could be true in the sense that this may happen more often due to storm waves or whatever, but considering the (apparently) sparse number of such events, it's hard to find a trend, so unless this kind of thing could be expected as a result of something else, there isn't much to go on. "2004 Indian Ocean Tsunami Biggest in 600 Years" - "turns out to be more evidence of tectonic upset." - it was a tectonic upset, but not the kind for which a correlation to multidecadal climate trends would be expected. On the Arctic Oscillation - "Synchronized Chaos: Mechanisms For Major Climate Shifts" - I will have to read the paper referenced by the article. I suspect though that more is understood about how CO2 would affect climate than is about these kinds of things. The other two: they suggested global warming could be behind the trend in the AO, or at least some portion of it. Of course there is internal variability, and some unforced variation in AO will occur. (?) AO itself doesn't seem to cause much of a global average temperature change (? - if the change in temperature at midlatitudes is balanced by that in the polar region).
129396. Dan Pangburn at 12:34 PM on 11 November 2008
        Models are unreliable
        Chris is not only unaware of a well established part of science but apparently refuses to consider it. Dynamic Systems Theory is readily applied to global average temperature history and easily proves that there is no significant NET positive feedback. Instead we get parochial rationalizations and erroneous estimates of future temperature as calculated by flawed computer programs that mistakenly invoke significant net positive feedback. The current UAH satellite numerical temperature anomaly data (these data consist of the differences of lower atmospheric temperature from the 1979 thru 1998 average) are at http://vortex.nsstc.uah.edu/data/msu/t2lt/uahncdc.lt . According to these data, the AVERAGE GLOBAL TEMPERATURE for the first 10 months of 2008 is LOWER than the average from 2000 thru 2007 by an amount equal to 40.3% of the total linearized increase (NOAA temperature anomaly data from ftp://ftp.ncdc.noaa.gov/pub/data/anomalies/annual.land_and_ocean.90S.90N.df_1901-2000mean.dat) during the 20th century. Since 2000, the CARBON DIOXIDE LEVEL HAS INCREASED by 14.4% of the total increase since the start of the Industrial Revolution (from several sources which are given on the fourth graph in the Middlebury link at 41 above). None of the GCMs predicted anything remotely close to this decline of average global temperature with rising atmospheric carbon dioxide level. The GCMs are little more than glorified curve fitting to historical data and apparently have negligible predictive capability. It will probably need to get much colder for some people to realize that they may be missing something. As the carbon dioxide level continues to increase and the average global temperature doesn’t, many people are looking more and more foolish.
129397. chris at 09:56 AM on 11 November 2008
        Evaporating the water vapor argument
        Well yes Venus gives us an idea of what can happen when a greenhouse effect runs out of control. Of course it's not going to happen on Earth. However we do know the total amount of potentially accessible fossil fuels, and if all of this was dug up and burned along with all the methane hydrates and shales and tar sands and peat and all forms of coal and gas and oil, the total warming would be rather dramatic. New Scientist did a report a year or so ago of an analysis of the projected warming...around 12 oC I think. So if we continue burn fossil fuels with present gusto we do have the potential to add a rather awesome amount of CO2 (and water vapour) into the atmosphere, and this will add a rather large amount of thermal energy to the Earth's climate. And of course since the time to achieve the new equilbrium temperature lags the forcings by a significant amount, the Heat In will be out of balance with the Heat Out for a while until the climate system adjusts to fluctuate around a new equilibrium temperature that is higher than it would be without the additional greenhouse forcings. That's all pretty obvious isn't it!
129398. chris at 08:54 AM on 11 November 2008
        Water vapor is the most powerful greenhouse gas
        Hmmm...You've made some odd misinterpretations of my post again. If you read the two sentences following "THREE" in my post just above (#24) you can see that water vapour makes a significant effect. Since this is water vapour that re-equilibrates in the atmosphere in response to anthropogenic CO2-induced warming it can be classed as anthropogenic water vapour (AWV). And I certainly didn't say that "the atmospheric total of WV remains more or less constant because of precipitation". If you read the two sentences following "THREE" in my post just above, it states: "AS the entire troposphere warms under the influence of cumulatively enhanced CO2 concentrations, so the atmospheric water vapour concentration rises." I'm not sure how you can interpret a statement that the WV rises as meaning that "the WV remains constant"! Of course the atmospheric WV fluctuates. It varies according to the local atmospheric temperature (and pressure). However on average the amount of atmospheric water vapour rises as the atmospheric temperature rises on average in a warming world. This can be measured in the real world. And any water vapour that doesn't partition into the atmosphere according to the local temperature and pressure just falls right out again as precipitation. If we doubled the amount of water that we pumped into the near ground atmosphere that doesn't change the fact that it is ultimately the local atmospheric temperature and pressure that governs the amount of water vapour in the atmosphere. Anything else that's pumped up there just falls right out again as precipitation. The NOAA site gives a pretty basic description although it's a bit out of date with respect to the determination of tropospheric water vapour in response to greenhouse warming.
129399. chris at 08:18 AM on 11 November 2008
        It's the sun
        Not really Quietman. It wouldn't make a noticeable difference! And in fact you've got it the wrong way round. If we removed the catalytic converter a tiny proportion of the CO2 otherwise pumped into the atmosphere would remain unoxidised to CO2 (and left as hydrocarbon or carbon monoxide). Since this tiny, tiny amount is from 13C-depleted fossil fuels, it would RAISE the 12C/13C ratio (since we would be failing to add to the atmosphere a tiny, tiny amount of 13C-depleted CO2). Of course that's all academic. The point is that we know very well from at least three seperate types of measurement (including the measurement of carbon isotopes in CO2) that the massive increased atmospheric concentrations of carbon dioxide, and the massive partitioning of carbon dioxide into the oceans, is the result of massive digging/pumping up and oxidation of long-sequestered fossil fuels.
129400. Mizimi at 06:43 AM on 11 November 2008
        Evaporating the water vapor argument
        Venus? A lot nearer to the sun than the earth so TSI is a lot higher. CO2 concentration (if I remember rightly) is 30,000 times greater. Galileo probe showed an enormous amount of IR being retained by sulphuric acid cloud cover. No atmospheric water as it has all been dissociated and blown away ( Venus has virtually no magnetic field. Not a good comparison. So, no, Venus gives us no clues at all.

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