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Comments 129651 to 129700:

129651. chris at 08:32 AM on 11 October 2008
        Can animals and plants adapt to global warming?
        Re #56 That's not really true Mizimi and your argument has a self-defeating element to it. ONE: If one addresses the fossil fuel reserves in relation to estimated recoverable sources rather than proven reserves (the values of which continually increase as new reserves are found), there is a whole lot more fossil fuel with potential for mining. Atmospheric CO2 levels can go way higher than 500 ppm. The US department of energy (DOE) estimate, that the proved[***] reserves for oil and gas are: 1.14-1.33 trillion barrels of oil (equivalent to around 43 years worth) 6.2-6.4 trillion cubic feet of natural gas (equivalent to around 160 years worth) and estimated recoverable coal (anthracite, bituminous, lignite and subbituminous): 1 million, million short tons of coal (equivalent to more than 400 years worth). oil and gas (Aug 27th 2008 update): http://www.eia.doe.gov/emeu/international/reserves.xls coal: http://www.eia.doe.gov/pub/international/iea2005/table82.xls [***] Proved reserves are estimated quantities that analysis of geologic and engineering data demonstrates with reasonable certainty are recoverable under existing economic and operating conditions. Burning all of that fossil fuel will take atmospheric CO2 levels way, way above 500 ppm. We're talking more like 1200-1500 ppm TWO: the obvious solution. Your approach to this is extraordinary. You're seemingly totally accepting of widescale extinction (you and Quietman consider this is just "natural")...you suggest that the "likely future for" your "grandchildren is one of energy poverty" and that "the most likely candidate for an extinction event is "Homo Sapiens Civilis""...and yet you consider that it's worthwhile propagandising against the science that might (and is, happily) help us in addressing these rather obvious problems. There is a solution to your grandchildrens "energy poverty" and your suggestion of "Homo Sapiens Civilis potential "extinction" (you suggest they're the "most likely candidate"). It's to address the problem with a bit of maturity and rationality. We take sequential steps towards switching our energy supplies towards the sustainable supplies that are clearly the only possible future of mankind. However difficult that may be, it solves all of the problems highlighted. Your grandchildren escape "energy poverty"...your "Homo Sapiens Civilis" escape "extinction"....the natural world avoids a wide-scale extinction (see top post by Barry Brook)...our descendants avoid massive, debilitating, and extraordinarily costly sea level rise...ocean acidification....enhanced drought in the central latitudes...enhanced extreme weather events....irrigation supply catastrophes and so on.... I have a feeling we might all be somewhere approaching the same wavelength on this!
129652. Mizimi at 05:44 AM on 11 October 2008
        Can animals and plants adapt to global warming?
        #46....Abstract: "Atmospheric carbon dioxide concentration is expected to exceed 500 parts per million and global temperatures to rise by at least 2 degrees C by 2050 to 2100," et seq.posts. One major problem the AGW argument has ( and one of the primary reasons I remain sanguine about the whole affair) is that of time. They seem to assume that there are endless supplies of fossil fuels just waiting to be used, and then make forward projections on that assumption. Recoverable coal reserves are currently estimated at 147 years supply based on current consumption. Oil production has peaked and estimated reserves = 40 years supply. Natural gas estimated reserves = 65 years. ( not including clathrates). So the likely future for my grandchildren ( who may live to see 2100, some 92 years away) is one of energy poverty - and potential devastating decline in civilisation (accelerated by 'energy wars'). So the most likely candidate for an extinction event is "Homo Sapiens Civilis" http://www.worldcoal.org/pages/content/index.asp?PageID=188 http://www.eia.doe.gov/emeu/international/reserves.html http://www.eia.doe.gov/basics/quickoil.html
129653. chris at 05:14 AM on 11 October 2008
        Can animals and plants adapt to global warming?
        Re #53 Quietman, it’s worth highlighting the essential difference between your (and Mizimi’s, apparently) and my view on extinctions in relation to global warming. I’ll outline this again, since according to your post #53 you don’t seem to understand what I am talking about. Both you and Mizimi dissociate yourself from the situation as it stands, discount the possibility that we might consider our role in potential species extinctions and what the consequences might be for our and our near descendents welfare, and consider this from the point of view of a rather carefree observer. Your attitudes are similar in nature to those that might enter a discussion on the steps we might take to reduce deaths from automobile accidents, by pointing out that it’s in the very nature of things that collide at high speeds that they become deformed from impacts, but that this is just a general law of physics, and we might actually find it “interesting” to observe these dispassionately. It’s difficult to come to any other conclusion based on your continual turning of the subject of this thread towards rather “potted” concepts of evolutionary "theory". You (and Mizimi) consider the situation to be “natural”, that things are just following “ the rule in evolution”, “evolution must take it’s course” and so on. Your comments in particular are extraordinary, since you seem to consider “extinction cycles” rather excellent, to the point of cheerleading for an extinction. And yet you seem oblivious to the evidence that (i) major extinction events are actually not that wonderful in practice to those involved and (ii) that the “interesting” consequences that you envisage take many hundreds of thousands or millions of years. Since the concerns of mature and far-sighted individuals is for the immediate future (the several decades to come), extending possibly towards events that might be set in motion now to impact our descendants of the coming century or two, it seems astonishing that someone would consider that it will be rather excellent to pursue a relatively near future of large scale extinction in the cerebral delight of considering what a wonderful evolutionary recovery might accrue a million years from now. A rather apocalyptic vision, in fact. There are surely some rational skeptical viewpoints with respect to the expectation of wide-scale warming-induced extinctions resulting from man-made enhancement of the earth’s greenhouse effect. One might have the view either that it’s not really warming (difficult to defend), that it won’t warm that much in the future (likewise difficult to defend, ‘though pretending that the greenhouse effect doesn’t exist certainly helps!), or that the warming won’t actually be a problem for species on a wide scale. In my opinion none of these is a comforting possibility when considered in the light of the evidence in the real world either as it exists now, or from paleo-analysis of events in the deep past. But the notion that we wash our hands of the entire business, and pursue self-defeating scenarios without consideration of their consequences, other than in the light of a cerebral interest in extinctions (one of your “favorite studies”), seems extraordinarily perverse if not downright repellent…
129654. chris at 04:25 AM on 11 October 2008
        Can animals and plants adapt to global warming?
        Re #53 Quietman I'm afraid that's nonsense. Making stuff up and telling untruths is not skepticism. On untruth: I cited some papers on the relationship between paleodata identifying cold (warm) spells in the deep past and data that identified contemporaneous lowered (raised) atmospheric CO2 levels. You make the ill-informed assertion (your post #43) that "The cited papers assumes that the sensitivity is as the IPCC hypothesizes." But of course they do nothing of the sort, as simple perusal of the papers would establish. Even 'though you clearly have no idea what you are talking about with respect to this work you chose to pursue that falsehood in your post #47. What is to be gained by making up stuff that simply isn't true Quietman? If pursuing an agenda position requires you to misrepresent the work of others, perhaps you should consider whether your agenda position is worth it! On your odd comments about the greenhouse effect: It really does seem that you don't believe in the greenhouse effect, which is rather astonishing. Your schoolboy notions about “open” and “closed” systems are rather dismal (happily a schoolboy would be unlikely to pursue such a level of ignorance!). Is the earth an open or a closed system Quietman? If not, what might a closed system encompass with respect to the solar system, for example? And why would anyone possibly attempt to pursue the notion that an obvious, well-characterized and undeniable phenomenon doesn’t exactly exist by using fallacious arguments based on semantics? In fact the solar system might be considered a closed system, and one could then ponder the distribution of the thermal energy arising from the powerhouse that sits at its “centre”. What happens to all that radiated heat, blasted into the sun’s surrounds in the form of radiation that covers large parts of the visible, UV, and IR regions of the spectrum? How about the earth? We know the size of the sun, its surface temperature, the size of the earth and can estimate a value for the earth’s overall albedo. This allows us to calculate the temperature of a “naked” earth bathed in the solar radiation. This was first done by Fournier in the early 19th century. The earth should be around 255K (-18 oC). We can do the same calculation now. Same result. We know this simple analysis is effective since we can apply it to other planets and determine their “black body” temperature. Spectroscopic analysis of the true planetary temperature is revealing of its atmospheric composition, and we can explore this further using spectroscopic detection of the atmospheric gases. So why is the earth so warm (a cozy ~288 K)? Already in the 19th century that was identified. It’s our atmospheric water vapour and carbon dioxide. These molecules (unlike the symmetric O2 and N2 that make up the vast proportion of our atmosphere) absorb infra-red radiation emitted from the earth following insolation, and reradiate the energy (or “bump” into surrounding atmospheric gas molecules increasing their kinetic energy, which, as you should know, is effectively equivalent to their “temperature”). How do we know that CO2 and water vapour absorb and re-radiate infra-red radiation? Because we can measure it directly. It’s a no-brainer Quietman. The greenhouse effect exists. The question then relates to the amount that the greenhouse efect warms us (e.g. the "climate sensitivity"). Since we know the infra-red absorptive properties of CO2 (and water vapour) we can calculate the radiative forcing that results in increasing the atmospheric CO2 concentration, for example. This forcing results in the retention of excess thermal energy by the suppression of the ability of surface infra-red to radiate freely into space. It’s a little like lying in your chilly bed in February, and putting a blanket on top of you. Is that a “closed system” Quietman? Not really. And yet you get warmer (else you’d probably not bother). The suppression of the escape of radiation into the surrounds (your bedroom or cold empty space) results in a shift in the equilibrium temperature of the surface of the body “protected” by the thermal “blanket” to a higher value. The full effect of raising atmospheric CO2 levels on the earth’s temperature is realized by feedbacks. The most important one is the rise in atmospheric water vapour concentrations as the atmosphere warms under the influence of enhanced CO2. Does this increase in atmospheric water vapour in the atmosphere actually occur? Yes it does Quietman. How do we know? Because we can measure it. And so on.
129655. Quietman at 23:51 PM on 10 October 2008
        Can animals and plants adapt to global warming?
        chris Evolution and extinction go hand in hand, I never changed the subject. As to the rest of your comment I have no idea what you are talking about. On my "untruth", Green house is a known effect in a closed system, an unknown in an open system, if more than a hypothesis in an open system then prove it. A theory requires proof, not consensus. Show me the physical evidence that it works they way you indicate.
129656. chris at 22:21 PM on 10 October 2008
        Evaporating the water vapor argument
        re #15 "Heat in = Heat out, No?" No. Heat in doesn't equal heat out. With enhanced greenhouse forcing under constant insolation, Heat in is greater than Heat out (Heat in > Heat out)...in other words it gets warmer, until the effects of the enhanced forcing reach equilibrium. At that point Heat in does equal Heat out, but the system retains a greater amount of thermal energy. The world is warmer. That's not difficult to understand. And as we all know rather well, since simple physics, theory, simulation and real world measurements indicates this to be the case, a warmer atmosphere supports a larger water vapour concentration, and so as the earth warms under the influence of enhanced atmospheric CO2 concentrations, this warming results in an enhanced water vapour concentration. Since water vapour is itself a very strong greenhouse gas, this results in feedback warming. So enhanced atmospheric CO2 "adds" thermal energy (warmth) to the earth's climate system, and the resultant enhanced water vapour concentrations "adds" additional thermal energy (warmth). So it really requires rather awesome bottom-squirming semantic quibbling to pursue the fallacy that enhanced greenhouse gas concentrations "cannot "add" anything"... ..or are you suggesting that the greenhouse effect doesn't exist?!
129657. chris at 20:21 PM on 10 October 2008
        It's the ocean
        Re #3 Quietman which maps are you referring to (in relation to your statement about warming on ridge lines)?
129658. Patrick 027 at 15:08 PM on 10 October 2008
        Climate sensitivity is low
        Last comment posted before seeing your last comment - "John allows links and actually prefers hyperlinks. But he has asked us to keep the discussion pertinent to the thread and not post "lists of links" so I try to break up my comments for readability." Duly noted. (I know I wandered a bit from 'Volcanoes' in the prior segment of discussion... part of it was centered on tides and that naturally expanded to other things...) "PS I looked at your remark on THERMODYNAMICS but skipped"..." Articles and Papers are much more appreciated as links (less opinion and more facts)." That's fine - the rest of my RealClimate comments I listed above were for just in case you were interested (many covering topics we discussed back at Science and Society, but each time I write something I don't do it the exact same way, so... etc.). I did have some RC comments on radiative physics in the atmosphere in particular and when I finnish tracking those down I will post a reference to those and ONLY those.
129659. Patrick 027 at 14:53 PM on 10 October 2008
        Climate sensitivity is low
        I decided to repost some comments at http://blogs.abcnews.com/scienceandsociety/2008/07/global-warming.html#comments - The comments about Monckton's paper, at least one (big) one of which was deleted from that website, hence this repost: --- MORE ARTFULLY WRITTEN CRITIQUES FOUND AT RealClimate: "Once more unto the bray", DELTOID: "Monckton's Triple Counting" MONCKTON'S PAPER "Climate Sensitivity Reconsidered": (Monckton has a prior record of demonstrating an apparent lack of accuracy in this subject matter.) INTERNAL VARIABILITY --"[G]LOBALLY-AVERAGED land and sea surface absolute temperature TS has not risen since 1998 (Hadley Center; US National Climatic Data Center; University of Alabama at Huntsville; etc.). For almost seven years, TS may even have fallen (Figure 1). There may be no new peak until 2015 (Keenlysideet al., 2008)." "The models heavily relied upon by the Intergovernmental Panel on Climate Change (IPCC) had not projected this multidecadal stasis in “global warming”; " Of course they haven't, because: 1.the timing of specific cases of such short term interannual to decadal variability is not so important to longer term climate trends, and even to the extent that models may reproduce the general characteristics of variability, such variations get averaged to near-zero in combining multiple runs of models. 2. 1998 was extra warm because of the El Nino. There will be, in any given period of sufficient length, some number of warmer years and cooler years relative to any longer trend. One can't conclude there is/has been a 'stasis', especially a 'multidecadal stasis', in the warming. ________ --"nor (until trained ex post facto) the fall in TS from 1940-1975;" what 'trained'? --"nor 50 years’ cooling in Antarctica (Doran et al., 2002)" Ozone hole has a regional effect there, and I can't take Monckton's word for it that the Antarctic has cooled for as long as 50 years. Anyway, at least a part of it have warmed. --"and the Arctic (Soon, 2005);" The arctic has been warming. --"nor the onset, duration, or intensity of the Madden-Julian intraseasonal oscillation, "... Models can't reproduce all aspects of internal variability yet. So they aren't perfect. That doesn't invalidate all of what they can do. --"(oceanic oscillations which, on their own, may account for all of the observed warmings and coolings over the past half-century: Tsoniset al., 2007);" Then where has all the warming from greenhouse gases gone? The rest of that paragraph - short term variability, so what. Medieval Warm Period - perhaps mainly a Northern Hemisphere or European phenomenon; not so big globally. Warming on other planets - Pluto's temperature response to the eccentricity in it's orbit lags the forcing due to thermal inertia; what warming on Jupiter? (recent circulation changes may be an internal variability - which, I believe, was predicted by a model!); Mars' albedo is affected by Dust storms, and is the warming global? Earth's climate history is understood generally better than those of other planets. Solar Grand Maximum - is it grand enough? ________ Reproduction of Hansen's graph from 1988: - it's a mischaracterization; for the emissions scenario we've most closely followed, the temperatures have followed quite closely thus far. ________ CLIMATE VS WEATHER --"The climate is “a complex, non-linear, chaotic object” that defies long-run prediction of its future states (IPCC, 2001), unless the initial state of its millions of variables is known to a precision that is in practice unattainable," He's confusing climate with weather and ignoring different timescales. --"combined with a heavy reliance upon computer models unskilled even in short-term projection, with initial values of key variables unmeasurable and unknown, with advancement of multiple, untestable"" so what? This isn't weather prediction. ________ DEFINITIONS --"consequent increase in aggregate forcing (from Eqn. 3 below) of ~0.26 W m–2, or <1%. That is one-twentieth of the value stated by the IPCC. The absence of any definition of “radiative forcing” in the 2007 Summary led many to believe that the aggregate (as opposed to anthropogenic) effect of CO2 on TS had increased by 20% in 10 years. The IPCC – despite requests for correction – retained this confusing statement in its report." Anyone who's confused could have looked at the other numbers given by the IPCC to figure it out. In the context of climate CHANGE radiative forcing is often discussed as the CHANGE from some reference level. ________ --"non-Popper-falsifiable theories," Give it time and we'll see. So far things are happenning that have been expected. But for the purposes of public policy, this could also be seen to a degree as an application of scientific knowledge already gained - we know A, B, C, so we expect if we do D we'll get E. etc. --"and, above all, with the now-prolonged failure of TS to rise as predicted (Figures 1, 2), raise questions about the reliability and hence policy-relevance of the IPCC’s central projections."" There has not been such a prolonged failure. We expect a few bumps and dips. ________ feedbacks: Unless otherwise specified, the climate sensitivity to radiative forcing by a doubling (or whatever change) of CO2 is based on the radiative forcing of the doubling of CO2, whatever the source of CO2 is, including feedbacks. --"For this and other reasons, it is not possible to obtain climate sensitivity numerically using general-circulation models: for, as Akasofu (2008) has pointed out, climate sensitivity must be an input to any such model, not an output from it." Nonsense. Climate sensitivity is input only implicit - it is the evaluation of model output that can determine explicitly what the sensitivity is. ________ Radiative forcing: This is basic physics; if the amount and the radiative properties are known, radiative forcing can be calculated. For CO2 and generally other gases, both are known quite well. Some things about clouds are known, but the feedbacks from changes in the amount of different types of cloud in different places is a source of uncertainty. In so far as external radiative forcing, I think aerosols have the greatest uncertainty, in part because of more complex effects. ________ --"The signature or fingerprint of anthropogenic greenhouse-gas forcing, as predicted by the models on which the IPCC relies, is distinct from that of any other forcing, in that the models project that the rate of change in temperature in the tropical mid-troposphere – the region some 6-10 km above the surface – will be twice or thrice the rate of change at the surface (Figure 4):" That's a general tendency with any global warming - it isn't as apparent in the graph for the response to solar forcing because the solar forcing used is so small in comparison. The fingerprint of increased greenhouse gases is cooling of the upper atmosphere, which has occured, and is not expected from a positive solar forcing. Granted that the response to ozone changes is more similar to greenhouse gas forcing (though there are differences), but it wouldn't make sense to arbitrarily suppose we can't tell at all how much is from what, especially given knowlege of radiative forcing. --"However, as Douglass et al. (2004) and Douglass et al. (2007) have demonstrated, the projected fingerprint of anthropogenic greenhouse-gas warming in the tropical mid-troposphere is not observed in reality. Figure 6 is a plot of observed tropospheric rates of temperature change from the Hadley Center for Forecasting. In the tropical mid-troposphere, at approximately 300 hPa pressure, the model-projected fingerprint of anthropogenic greenhouse warming is absent from this and all other observed records of temperature changes in the satellite and radiosonde eras:" The radiosonde record may have a bias due to the nature of the devices used. There has been some disagreement but I think the satellite record turned out to reveal tropospheric warming and stratospheric cooling, as expected, though off hand I don't know about the distribution within the troposphere. The graph shown appears to indicate tropospheric warming and stratospheric cooling, which seems to support the idea of greenhouse-forcing induced warming. --"There are two principal reasons why the models appear to be misrepresenting the tropical atmosphere so starkly. First, the concentration of water vapor in the tropical lower troposphere is already so great that there is little scope for additional greenhouse-gas forcing." Interesting, but increasing water vapor higher in the troposphere would still have important effects. --"Secondly, though the models assume that the concentration of water vapor will increase in the tropical mid-troposphere as the space occupied by the atmosphere warms, advection transports much of the additional water vapor poleward from the tropics at that altitude." That likely only would happen if the water vapor amount increases in the tropics at that altitude. Increased water vapor in the tropics and increased advection of water vapor don't contradict the other - they should tend to go together. --"Since the great majority of the incoming solar radiation incident upon the Earth strikes the tropics, any reduction in tropical radiative forcing has a disproportionate effect on mean global forcings." Only in the wavelengths dominated by solar radiation (SW radiation; the greenhouse effect deals with LW radiation - it too can vary with latitude, but ...). --"On the basis of Lindzen (2007), the anthropogenic-ear radiative forcing as established in Eqn. (3) are divided by 3 to take account of the observed failure of the tropical mid-troposphere to warm as projected by the models –" This is nonsense. The radiative forcing being considered is clearly the external forcing. What is being asserted here is that the feedbacks are not the same as expected - distinctly different, even if it were correct. None of this discussion justifies dividing external radiative forcing by 3 or any number. ----------- PS Lindzen himself, though not free of mistakes in general, did not make this same mistake in the work Monckton is citing. See DELTOID: "Monckton's triple counting" I didn't go into a lot of Monckton's statements over k (seems like a waste of time considering...) but see the DELTOID work just mentioned, which states: --"What Monckton is doing is double counting his (dubious) evidence that sensitivity is lower than the IPCC number. If he had two pieces of evidence that sensitivity is half the IPCC number he would multiply them together to claim that sensitivity is one quarter the IPCC number. This is not correct." PS this DELTOID writing is far more brief than what I wrote here. ----------- --"it is simple to calculate that, in 2001, one of the IPCC’s values for f was 2.08. Thus the value f = 3.077 in IPCC (2007) represents a near-50% increase in the value of f in only five years." He's comparing one value to what? An average? That's an odd way to assert a 50 % increase. --"With these assumptions, ? is shown to be less, and perhaps considerably less, than the value implicit in IPCC (2007). The method of finding ? shown in Eqn. (24), which yields a value very close to that of IPCC (2007), is such that progressively smaller forcing increments would deliver progressively larger temperature increases at all levels of the atmosphere, contrary to the laws of thermodynamics and to the Stefan-Boltzmann radiative-transfer equation (Eqn. 18), which mandate the opposite." Well, that's odd, since IPCC temperature projections increase with increasing radiative forcing. I didn't bother to check whether Monckton's application of Stefan-Boltzman was correct or not. --"the feedback-sum b cannot exceed 3.2 W m–2 K–1 without inducing a runaway greenhouse effect. " I think he's misunderstanding something here. I suspect the IPCC listing of feedbacks are in total after taking into account their responses to each other. --"Figure 7" "Fluctuating CO2 but stable temperature for 600m years" The sun increases in brightness over hundreds of millions of years, so the same CO2 level 500 million years ago would allow a cooling relative to now. CO2 forcing is roughly logarithmic to changes in concentration within a certain range; An increase from 280 ppm to 7000 ppm is 4.64 doublings. 7000 ppm is one of the higher estimates of CO2 for that time period. Not shown is a possible dip in CO2 in the late Ordivician. The temperature graph is unrealistic and cartoonish (which may be fine for some purposes, but not here) and no one can say that global average surface temperature has not exceeded 22 deg C during the time span shown. --"The Bode equation, furthermore, is of questionable utility because it was not designed to model feedbacks in non-linear objects such as the climate." Yes, that's what the climate models are for. --"since CO2 occupies only one-ten-thousandth part more of the atmosphere that it did in 1750" That's over 30% relative to CO2 concentration in 1750. Which is enough for CO2. ________________________________________________________ The other (opposing) paper "A Tutorial on the Basic Physics of Climate Change": A decent brief overview for introductory purposes, although they leave themselves open to not taking into account convection and variations in optical properties over wavelength. But the IPCC, etc. findings certainly do take into account these things. For more, see my attempt to explain it qualitatively but clearly at "Tropical Storm Bertha" I mention there a particularly useful book (draft copy available online) by Ray Pierrehumbert: "Principles of Planetary Climate". _____________________________________________ CLARIFICATION/CORRECTION: --"Since the great majority of the incoming solar radiation incident upon the Earth strikes the tropics, any reduction in tropical radiative forcing has a disproportionate effect on mean global forcings." I wrote: "Only in the wavelengths dominated by solar radiation (SW radiation; the greenhouse effect deals with LW radiation - it too can vary with latitude, but ...). " Actually, I should have just said No. Because radiative forcing is what it is; that it might be a smaller percentage of the radiative fluxes in the tropics if it itself doesn't vary in latitude much is irrelevent for finding the global average. Actually, invariance over latitude invariance isn't the case - direct forcing by increases of CO2 and some other greenhouse gases is greatest in the subtropics and least in polar regions; the near surface climate response is opposite that pattern because of the distribution of feedbacks - albedo feedbacks of less winter snow (at latitudes that get winter sun) and summer polar sea-ice loss (open water stores solar heat and releases it in the dark polar winter, delaying ice formation), and greater evaporative cooling of tropical waters which reduces surface warming but contributes (upon condensation) to the warming of the middle-to-upper troposphere. ----------------------- 3.models can not reproduce every aspect of the weather and climate system exactly - this does not mean they are not very useful. The apparent reduced warming of the mid to upper low-latitude troposphere would be just as puzzling if the cause of warming were solar brightenning.
129660. chris at 10:55 AM on 10 October 2008
        Can animals and plants adapt to global warming?
        Re #49: It's encouraging that you consider that we should address the acidification of the oceans. However fertilizer runoff makes a trivial contribution to ocean acidification, although it does have seriously degrading effects on streams and rivers, and can cause largescale esturial deadzones as a result of promotion of seasonal algal blooms followed by de-oxygenation (e.g. see seasonal de-oxygenation around Chesapeake Bay and the Mississippi delta in the Gulf of Mexico). What is causing the accelerating acidification of the worlds oceans? It's our CO2 emissions Quietman. Around 40-50% of our CO2 emissions are absorbed by the oceans, and this humungous amount is causing the oceans to acidify [CO2 + H2O <-----> H2CO3 <------> HCO3- + H+ <----> CO32- + H+; remember that H+ is acid] Try: Feely, RA et al (2004) "Impact of anthropogenic CO2 on the CaCO3 system in the oceans" Science 305, 362-366. Abstract: "Rising atmospheric carbon dioxide (CO2) concentrations over the past two centuries have led to greater CO2 uptake by the oceans. This acidification process has changed the saturation state of the oceans with respect to calcium carbonate (CaCO3) particles. Here we estimate the in situ CaCO3 dissolution rates for the global oceans from total alkalinity and chlorofluorocarbon data, and we also discuss the future impacts of anthropogenic CO2 on CaCO3 shell forming species. CaCO3 dissolution rates, ranging from 0.003 to 1.2 micromoles per kilogram per year, are observed beginning near the aragonite saturation horizon. The total water column CaCO3 dissolution rate for the global oceans is approximately 0.5 +/- 0.2 petagrams of CaCO3-C per year, which is approximately 45 to 65% of the export production of CaCO3." Sabine, CL et al. (2004) "The oceanic sink for anthropogenic CO2" Science 305, 367-371. "Using inorganic carbon measurements from an international survey effort in the 1990s and a tracer-based separation technique, we estimate a global oceanic anthropogenic carbon dioxide (CO2) sink for the period from 1800 to 1994 of 118 +/- 19 petagrams of carbon. The oceanic sink accounts for similar to48% of the total fossil-fuel and cement-manufacturing emissions, implying that the terrestrial biosphere was a net source of CO2 to the atmosphere of about 39 +/- 28 petagrams of carbon for this period. The current fraction of total anthropogenic CO2 emissions stored in the ocean appears to be about one-third of the long-term potential." The effects of this acidification on oceanic life is reviewed recently here and is rather relevant to the subject of this thread: Hoegh-Guldberg O et al. (2007) "Coral reefs under rapid climate change and ocean acidification" Science 318, 1737-1742. Abstract: "Atmospheric carbon dioxide concentration is expected to exceed 500 parts per million and global temperatures to rise by at least 2 degrees C by 2050 to 2100, values that significantly exceed those of at least the past 420,000 years during which most extant marine organisms evolved. Under conditions expected in the 21st century, global warming and ocean acidification will compromise carbonate accretion, with corals becoming increasingly rare on reef systems. The result will be less diverse reef communities and carbonate reef structures that fail to be maintained. Climate change also exacerbates local stresses from declining water quality and overexploitation of key species, driving reefs increasingly toward the tipping point for functional collapse. This review presents future scenarios for coral reefs that predict increasingly serious consequences for reef- associated fisheries, tourism, coastal protection, and people. As the International Year of the Reef 2008 begins, scaled- up management intervention and decisive action on global emissions are required if the loss of coral- dominated ecosystems is to be avoided. " The oceans will gradually lose their ability to absorb large fractions of our emissions and atmospheric greenhouse gas levels will be enhanced as a result. Already there is evidence that this effect is beginning to be apparent: Le Quere C et al (2007) "Saturation of the Southern Ocean CO2 sink due to recent climate change" 316, 1735-1738. Abstract: "Based on observed atmospheric carbon dioxide (CO2) concentration and an inverse method, we estimate that the Southern Ocean sink of CO2 has weakened between 1981 and 2004 by 0.08 petagrams of carbon per year per decade relative to the trend expected from the large increase in atmospheric CO2. We attribute this weakening to the observed increase in Southern Ocean winds resulting from human activities, which is projected to continue in the future. Consequences include a reduction of the efficiency of the Southern Ocean sink of CO2 in the short term (about 25 years) and possibly a higher level of stabilization of atmospheric CO2 on a multicentury time scale."
129661. chris at 10:20 AM on 10 October 2008
        Can animals and plants adapt to global warming?
        Re # 48 [chris said: "We know things are going to become increasingly problematic in a warming world"] [Quietman replied: "Not! Again assumption based on a hypothesis. Just because a belief is accepted does not make it true, it's like saying God did it."] No. It's not an "assumption based on a hypothesis"...it's a conclusion based on the evidence. If we don't address the evidence we're in trouble. We can't address future consequences by ignoring the evidence and putting our money on things that we know not to be true.
129662. chris at 09:50 AM on 10 October 2008
        Water vapor is the most powerful greenhouse gas
        #4 and #6 Mizimi - please think before posting: #4: Water vapour amplifies whatever source of warming caused the atmosphere to warm,since atmospheric warming results in raised atmospheric water concentrations. And water vapour is a greenhouse gas as we all know very well. If the earth's atmosphere cools so the water vapour drops AMPLIFYING the primary cooling effect. Amplification is exactly what water vapour does with respect to thermal effects on atmospheric temperature. It's exactly the right term to use. There's nothing "emotively biased" about it! ------------------------------- Greenhouse gases apply a thermal FORCING. Forcing is an appropriate word to use since greenhouse gases do not instantaneously warm the atmosphere (and indirectly the surface). The apply a constant forcing that results in a shift in the atmospheric (and indirectly the surface) temperature towards a higher equilibrium value. There's nothing "emotively biased" about using appropriate terms. Sadly we can't "magic away" reality by semantic quibbling! --------------------------------- #6: Re feedbacks. Water vapour is the dominant greenhouse gas in the earth's atmnosphere. Together with CO2, water vapour supplements the earth's black body temperature (around minus 15 oC) with around 30 oC of enhanced warmth. This has been known and understood since the middle of the 19th century. How you can pretend that water vapour cools the atmosphere is a mystery. If only we could magic away problematic reality by asserting that things are exactly opposite to what they are in reality! It's easy to highlight your dull fallacy. You state -Mizimi: "Water vapour is present in the upper troposphere; thus it radiates heat outwards and has a cooling effect". Let's pretend first that the water vapour wasn't there: the infra-red radiation emitted from the earth's surface just passes freely into space. Now add back the water vapour. The water vapour absorbs the IR radiation emitted from the earth's surface AND RADIATES IT IN ALL DIRECTIONS EQUALLY (as well as passing kinetic energy to other gas molecules in its surrounds). In other words it suppresses the ability of infra-red radiation emitted from the earth to pass unhindered to space. In other, other, words it warms the atmosphere. Let's not make up stuff to pursue the pretence that we don't know what we do know!
129663. chris at 06:58 AM on 10 October 2008
        Can animals and plants adapt to global warming?
        Re #47 Quietman, you've rather changed the subject in your response. My response in post #44 was to your comment in #41. But we're getting used to that... Let's switch to your new slant..that extinction drives evolution. Fine, that's a supportable statement. Stephen Jay Gould's "Wonderful Life" is a decent example. It shows that evolution potentially leads to the flourishing of novel life forms within the "empty" niches that result from major extinctions, as characterised by the Cambrian expansion of forms identified within the Burgess Shale. But you are resorting again to your dissociated non-humanism: "Wouldn't it be interesting if we had another major extinction....in several hundred thousand or a few million years afterwards what a fascinating diversity of life forms might arise..." If you want to go there, that's fine. But the rest of us would prefer not to pursue a relentless drive towards the next major extinction. That's not a future that the overwhelming majority of humanity wishes to pursue, however interesting you might consider it. The fact is that the evidence indicates rather strongly that rapid global scale warming are associated with major extinctions in the earth's history. We can pretend that the greenhouse effect doesn't exist and pursue "interesting" catastrophic scenarios. In real life I suspect that we're going to be rather more mature and rational, and direct our focus onto the coming decades and few centuries (rather than an "interesting" post-extinction potential diversification some millions of years in the future). Re the greenhouse effect: I'm afraid the greenhouse effect is a fact Quietman. Our (sciences's) understanding of the world is not defined by one individuals ignorance. Re "assumptions" and the "IPCC" You've got that wrong again. You've said something in your post #43 that simply isn't true. If one has to contrive untruths and then pursue these to attempt to make a point, then the point is really not worth making, is it. To reiterate, the work described in the papers/reviews I cited in my post #35 make no assumptions whatsoever about the supposed "climate sensitivity" or any supposed "hypotheses" of the IPCC. Untruths do not equate to "skepticism".
129664. DB2 at 05:45 AM on 10 October 2008
        Is Antarctic ice melting or growing?
        Forests play an important role in carbon sequestration. This research finds that net primary productivity in temperate forests would increase 25% with a carbon dioxide concentration of 550 ppm. Boreal forests would see an increase of 15% while tropical forest would increse NPP by 35%. CO2 fertilization in temperate FACE experiments not representative of boreal and tropical forests Thomas Hickler et al. Global Change Biology (2008) 14, 1531–1542 http://face.env.duke.edu/PDF/gcb14-08c.pdf Abstract: Results from free-air CO2 enrichment (FACE) experiments in temperate climates indicate that the response of forest net primary productivity (NPP) to elevated CO2 might be highly conserved across a broad range of productivities. In this study, we show that the LPJ-GUESS dynamic vegetation model reproduces the magnitude of the NPP enhancement at temperate forest FACE experiments. A global application of the model suggests that the response found in the experiments might also be representative of the average response of forests globally. However, the predicted NPP enhancement in tropical forests is more than twice as high as in boreal forests, suggesting that currently available FACE results are not applicable to these ecosystems. The modeled geographic pattern is to a large extent driven by the temperature dependence of the relative affinities of the primary assimilation enzyme (Rubisco) for CO2 and O2.
129665. DB2 at 05:42 AM on 10 October 2008
        Is Antarctic ice melting or growing?
        It is important to differential between precipitation and soil moisture. It is moisture in the soil that (land) plants can actually use. Climate models predict that a warmer world means drier soil, a result of more evaporation, with a resultant threat to our food supply. Two papers by Robock et al. look at historical soil moisture data to see if the real world has followed the models. Both paper can be found here by clicking on 'Recent Publications'. http://climate.envsci.rutgers.edu/soil_moisture/ The Global Soil Moisture Data Bank Bull. Amer. Meteorol. Soc. (2000) 81, 1281-1299 Forty five years of observed soil moisture in the Ukraine: No summer desiccation (yet) Geophys. Res. Lett. (2005) 32, L03401 The 2000 paper looked at data from the former Soviet Union, China, Mongolia, India and the US compared to GCM predictions. They found that "although this model predicts summer desiccation in the next century, it does not in general reproduce the observed upward trends in soil moisture very well." The trends of the data and model were in opposite directions. "In contrast to predictions of summer desiccation with increasing temperatures, for the stations with the longest records, summer soil moisture in the top 1 m has increased while temperatures have risen." In the 2005 paper they look at "the longest data set of observed soil moisture available in the world, 45 years of gravimetrically-observed plant available soil moisture for the top 1 m of soil, observed every 10 days for April-October for 141 stations from fields with either winter or spring cereals from the Ukraine for 1958-2002." They find that "the observations show a positive soil moisture trend for the entire period of observation, with the trend leveling off in the last two decades," noting that "even though for the entire period there is a small upward trend in temperature and a downward trend in summer precipitation, the soil moisture still has an upward trend for both winter and summer cereals." "Although models of global warming predict summer desiccation in a greenhouse-warmed world, there is no evidence for this in the observations yet, even though the region has been warming for the entire period."
129666. Quietman at 04:52 AM on 10 October 2008
        Climate sensitivity is low
        Patrick Science and Society is a good blog but Disney owns ABC and therefore the site and does not allow links. That is why an argument on AGW is better done here. John allows links and actually prefers hyperlinks. But he has asked us to keep the discussion pertinent to the thread and not post "lists of links" so I try to break up my comments for readability. PS I looked at your remark on THERMODYNAMICS but skipped most of the other links purely because I don't care to go to that web site. Articles and Papers are much more appreciated as links (less opinion and more facts).
129667. chris at 04:49 AM on 10 October 2008
        Climate's changed before
        interesting questions; some are easily answered, some less so: [Has any research been done on just how much water vapour can be held in the atmosphere and the warmer temperatures before it reaches saturation point?] It depends where you are in the atmosphere since the saturation level varies with temperature and pressure. These data are known quite acurately 'though. You can see the variation of saturation of air with water vapour as a function of temperature here (scroll down the page to find the relevant graph): http://en.wikipedia.org/wiki/Water_vapor [And also explain to me why Douglas Hoyt's info is so dodgy. He's fairly knowledgeable in the field so why is his contribution so wrong? How do we know what's right or wrong?] One can compare Hoyt's assertions with reality. They don't match. Therefore in this instance we know Hoyt is wrong. A problem is that Hoyt hasn't published anything on this. he's just asserting stuff on a web site. Since he may well have written it in 2004, perhaps he thought it was correct then but doesn't realize that real world data now contradicts his assertion; perhaps he just hasn't bothered to update his web site. We'd have to ask him... Hoyt has made the assertion (on his website) that gravity effects will eliminate 90% of the warming-induced enhancement of water vapour concentrations. The Minschwaner and Dessler paper that Hoyt refers to indicates a possibility of a much smaller reduction in enhanced water vapour. So even in 2004, Hoyt's assertion didn't match reality. Now we have much better measures of atmospheric water vapour, and it's clear that the atmospheric water vapour concentrations rise pretty much as predicted by theory and modelling. As well as the articles whose abstracts are listed in my post above, more recent analyses (see [**] below) of direct tropospheric water vapour demonstrate that the water vapour concentrations are rising in response to warming pretty much as predicted. So Hoyt is demonstrably wrong. [You can justify comments with 'scientific proof' but how do we know that it is correct?] It's not really about "proof". It's about the evidence. In this case Hoyt is making assertions that are directly contradicted by the evidence. So in this instance Hoyt is demonstrably wrong. A lot of the efforts in dealing with so-called "skeptical" (!) "arguments" is in pointing out their inherent self-contradictions. Hoyt is also wrong (it seems to me) on straightforward theoretical/empirical grounds that relate to the competing effects of gravity and thermal kinetic energy on isolated molecules in a vapour as I outlined in my post just above. [are you prepared to take someone's word for it?] Yes and no. If someone has a habit of dishonesty of course one would be foolish to take their word. Likewise if someone is respected for their honesty and diligence, I'm more likely to take them at face value. I am always skeptical of stuff that is asserted on this or that web site, and if one investigates further and finds that the asserter hasn't published the relevant work (or in this case hasn't published anything for 10 years), makes assertions that are not supported by any evidence, and upon further investigation, finds that the assertions are actually directly contradicted by real world evidence, then it would be foolish not to discount the assertions. One should be skeptical about these things! [Is there some corruption not only from the climate change skeptics but also from the IPCC and other anthropogenic climate change supporters?] Corruption is usually identifiable. Can you identify any IPCC "corruption"? I haven't come across any. That doesn't mean the IPCC are paragons of perfection! If anything the IPCC presentations are somewhat conservative. [It's all very interesting but doesn't everyone within this current issue have an agenda?] I wouldn't have said so. There's clearly a strong agenda position to misrepresent the science amongst certain quarters (you see quite a lot of it from a cohort of posters on this web site). In my experience the only "agenda" the scientists have is to get to the bottom of whatever topic their researching, preferably making some good discoveries along the way and publishing some well-respected and highly-cited papers. [***] Gettelman A and Fu Q (2008) “Observed and simulated upper-tropospheric water vapor feedback” J. Climate 21, 3282-3289. Abstract: “Satellite measurements from the Atmospheric Infrared Sounder (AIRS) in the upper troposphere over 4.5 yr are used to assess the covariation of upper-tropospheric humidity and temperature with surface temperatures, which can be used to constrain the upper-tropospheric moistening due to the water vapor feedback. Results are compared to simulations from a general circulation model, the NCAR Community Atmosphere Model (CAM), to see if the model can reproduce the variations. Results indicate that the upper troposphere maintains nearly constant relative humidity for observed perturbations to ocean surface temperatures over the observed period, with increases in temperature similar to 1.5 times the changes at the surface, and corresponding increases in water vapor ( specific humidity) of 10% -25% degrees C-1. Increases in water vapor are largest at pressures below 400 hPa, but they have a double peak structure. Simulations reproduce these changes quantitatively and qualitatively. Agreement is best when the model is sorted for satellite sampling thresholds. This indicates that the model reproduces the moistening associated with the observed upper-tropospheric water vapor feedback. The results are not qualitatively sensitive to model resolution or model physics.” Brogniez H and Pierrehumbert RT (2007) “Intercomparison of tropical tropospheric humidity in GCMs with AMSU-B water vapor data” Geophys. Res. Lett. 34, Article Number: L17812 Abstract: “We make use of microwave measurements of the tropical free tropospheric relative humidity (FTH) to evaluate the extent to which the water vapor distribution in four general circulation models is faithful to reality. The comparison is performed in the tropics by sorting the FTH in dynamical regimes defined upon the 500 hPa vertical velocity. Because microwave radiation penetrates non-rainy and warm clouds, we are able to estimate the FTH over most of the dynamical regimes that characterize the tropics. The comparisons reveal that two models simulate a free troposphere drier than observed (< 10%), while the others agree with the observations. Despite some differences, the level of agreement is good enough to lend confidence in the representation of atmospheric moistening processes. A climate change scenario, tested on two models, shows a tendency to maintain the FTH to an almost fixed value be it an ascending or a subsiding regime” ',
129668. Quietman at 04:42 AM on 10 October 2008
        Can animals and plants adapt to global warming?
        Re: "So self-preservation also informs us to act rationally to limit our greenhouse gas emissions. " It certainly won't hurt anything to do so but carried to extremes (read CO2) will hurt everybody. Take action on true pollutants. Acidification of the ocean - control fertilizer runoff for starters. Grow more C4 plants (thanks Mizimi) and stop forest destruction by evacuating southern California so they can;t start the damn fires.
129669. Quietman at 04:36 AM on 10 October 2008
        Can animals and plants adapt to global warming?
        Re: "We know things are going to become increasingly problematic in a warming world" Not! Again assumption based on a hypothesis. Just because a belief is accepted does not make it true, it's like saying God did it.
129670. Quietman at 04:34 AM on 10 October 2008
        Can animals and plants adapt to global warming?
        Chris Re: "You've mixed up "evolution" with "extinction"." Extinction drives Evolution by reducing diversity followed by rapid increases in diversity. I suggest Bob Bakker's book "The Dinosaur Heresies" and Steve Gould's "Wonderful Life" as a good place to start. Re: "That's a fact. Let's not pretend that we don't know what we do know." Not factual. It remains hypothetical until proven. It can be demostrated by math but only using assumptions as variables because not all variables have been accurately measured. That is why it was ignored for almost a century. Sooooo That's a fact. Let's not pretend that we don't know what we do know. Re: "They make no assumptions whatsoever" That is what an argument is. Why would anyone write a paper without an assumption (hypothesis). The GHG hypothesis has been discussed amongst paleontologists for about a hundred years now and has been widely accepted for various extinction hypotheses but we realize that it is a hypothesis and accept it as that.
129671. Quietman at 04:03 AM on 10 October 2008
        Is Antarctic ice melting or growing?
        PS I also grow a lot of rocks but as they are sediments with fossils from the upper carboniferous period, I don't mind at all.
129672. Quietman at 03:58 AM on 10 October 2008
        Is Antarctic ice melting or growing?
        chris "assumptions that unfortunately do not survive real world analysis/observation." My remark was from personal observation as stated. That is what I do in retirement, grow things. That is why I was questioning Mizimi in the solar thread about C3 versus C4 flora. I plant small patches of different types of fruit and vegetables on one acre (spaced so they do not interfere with each other), on half the remaining acres I manage the forest and on the other half I let it do it's thing. The half I am managing I spray foe Japanese Beetles on the wild berry bushes and tent worms in the trees as well as planting trees that were not found on the property to observe which grow best in this climate. What I have obsevered is that evergreens are not as hardy or grow as quickly as leafy trees and shrubs and that the wild fruit trees and bushes are doing as well as the domesticated ones that I planted, in fact extremely well while the white cedars I planted died after trying for two years. The red cedar is doing OK as are the different spruces, maples, oaks and apple trees but not the hickories. There were no rasberry bushes here when I bought this place in 2002 and now both halves are full of wild rasberry and blackberry bushes. I don't offer this as proof of anything, only to explain my statement since eastern PA has increased CO2 levels and is more humid than in the past but it really isn't any warmer in this area (in fact the local airport records indicate the opposite), but it seems to be warmer longer (shorter spring weather) but that is heresay and not verified.
129673. DB2 at 03:38 AM on 10 October 2008
        Is Antarctic ice melting or growing?
        Chris, that is a lot to respond to a one time. I will post some research articles as time allows. First, plant productivity has already increased. This article from 2003 indicates that global net primary production on the land increased 6% between 1982 and 1999. (NPP is the difference between the CO2 absorbed by plants during photosynthesis, and CO2 lost by plants during respiration.)` Changes in the world's oceans were not included. The authors write, "Our results indicate that global changes in climate have eased several critical climatic constraints to plant growth, such that net primary production increased 6% (3.4 petagrams of carbon over 18 years) globally." Climate-Driven Increases in Global Terrestrial Net Primary Production from 1982 to 1999 R.R. Nemani et al. Science (2003) Vol. 300 1560-1563 http://cybele.bu.edu/globalgarden/nemani01.pdf Climate predictions are also iffy on a regional basis, and I'll dig up an article or two on the limitations of regional models. For now, I'll remind ourselves of the great hue-and-cry over the Sahel two or three decades ago. Now it seems things aren't so bad. This article on the Sahel finds that it has experienced an increase in vegetative output that has been, as Olsson writes, "remarkable." A recent greening of the Sahel — trends, patterns and potential causes L. Olsson et al. Journal of Arid Environments 63(2005) 556–566 http://meteo.lcd.lu/globalwarming/Ollson/recent_greening_of_... Abstract: For the last four decades there has been sustained scientific interest in contemporary environmental change in the Sahel (the southern fringe of the Sahara). It suffered several devastating droughts and famines between the late 1960s and early 1990s. Speculation about the climatology of these droughts is unresolved, as is speculation about the effects of land clearance on rainfall and about land degradation in this zone. However, recent findings suggest a consistent trend of increasing vegetation greenness in much of the region. Increasing rainfall over the last few years is certainly one reason, but does not fully explain the change. Other factors, such as land use change and migration, may also contribute. This study investigates the nature of a secular vegetation trend across the Sahel and discusses several potential causative factors.
129674. Quietman at 15:04 PM on 9 October 2008
        Climate sensitivity is low
        Re: "Simple Question, Simple Answer… Not" Interesting comments from John Mashey: [[ John Mashey Says: 8 September 2008 at 2:31 PM “These people, typically senior engineers, get suspicious”. Please, can we get deeper than “senior engineers” - that really isn’t improving insight. If we want to do that, we need to probe a lot deeper than just “senior engineers”. Let me offer a speculation, although not yet a serious hypothesis: 1. SPECULATION Amongst technically-trained people, and ignoring any economic/ideological leanings: 1) Some are used to having a) Proofs OR b) Simple formulae OR c) Simulations that provide exact, correct answers, and must do so to be useful d) And sometimes, exposure to simulations/models that they think should give good answers, but don’t. 2) Whereas others: a) Are used to missing data, error bars, b) Complex combinations of formulae c) Models with varying resolutions, approximations, and that give probabilistic projections, often only via ensemble simulations. d) Models that are “wrong”, but very useful. My conjecture is that people in category 1) are much more likely to be disbelieving, whether in science, math, or engineering. 2. ANECDOTAL EXAMPLES: 1) In this thread, a well-educated scientist (Keith) was convinced that climate models couldn’t be useful, because he was used to models (protein-folding) where even a slight mismodel of the real world at one step caused final results to diverge wildly … just as a one-byte wrong change in source code can produce broken results. See #197 where I explained this to him, and #233 where light dawned, and if you’re a glutton for detail: #66, #75,l #89, #1230, #132, #145, $151, #166 for a sample. 2) See Discussion here, especially between John O’Connor & I. See #64 and #78. John is an EE who does software configuration management. When someone runs a rebuild of a large software system, everything must be *perfect*. There’s no such thing as “close”. Also in that thread, Keith returned with some more comments (#137) and me with (#146), i.e., that protein-folding was about as far away from climate modeling as you could get. 3) Walter Manny is a Yale EE who teaches calculus in high school. He’s posted here occasionally (Ray may recall him :-), and participated in a long discussion at Deltoid, and has strong (contrarian) views. In many areas of high school/college math, there are proofs, methods known for centuries, and answers that are clearly right or wrong. 4) “moonsoonevans” at Deltoid, in #21 & #32 describes some reasons for his skepticism, #35 is where light dawns on me. He’s in financial services, had experienced many cases where computer simulations done by smart people didn’t yield the claimed benefits. In #35 I tried to explain the difference. All this says that if one is talking with an open-minded technical person, one must understand where *they* are coming from, and be able to give appropriate examples and comparisons, because many people’s day-to-day experience with models and simulations might lead them to think climate scientists are nuts. 3. A FEW SPECIFIC DISCIPLINES & CONJECTURES 1) Electrical engineers (a *huge* group, of which only tiny fraction are here) Many EEs these days do logic design, which requires (essentially) perfection, not just in the design, but (especially) in simulation. Design + input =>(logic simulator) => results At any step, the design may or may not be bug-free, but the simulator *must* predict the results that the real design would do given the input, exactly, bit for bit. Many test-cases have builtin self-checks, but the bottom line is that every test-case yields PASS or FAIL, and the simulator must be right. Many people buy simulators (from folks like Cadence or Synopsys), and run thousands of computers day and night simulating millions of test-case inputs. But, with a million test-cases, they’re not looking for an ensemble that provides a distribution, they’re looking for the set of test-cases to cover all the important cases, and for EVERY one to pass, having been simulated correctly. This has some resemblance to the protein-folding problem mentioned above. Now, at lower levels of timing and circuit design, it isn’t just ones and zeroes (there’s lots of analog waveforms, probabilistic timing issues, where one must guarantee enough margin, etc). When I’d tease my circuit designer friends “Give me honest ones and zeroes”, they’d bring in really ugly, glitchy HSPICE waveforms and say “so much for your ones and zeroes”. (This is more like the molecular “docking” problems that Keith’s colleagues mentioned.) At these levels, people try to set up rules (”design rules”) so that logic designers can just act at the ones-and-zeroes level. If one looks at EEs who worry about semiconductor manufacturing, they think hard about yields, failure attribution, and live with time-series. (Standard answer to “We got better yield this month, how do you think it looks?” was “Two points don’t make a trend.” 2) Software engineers Programs often have bugs, but even a bug-free program can fall apart if you change the wrong one byte of code, i.e., fragile. (I don’t recall the source, but the old saw goes something like: if skyscrapers were like software, the first woodpecker would knock them over.) Configuration management / software rebuilds are fairly automated these days, and they must be correct. One cannot include the wrong version of code, or compile with incompatible options. Performance engineering and benchmarking tend to be more probabilistic-oriented, and although a lot of people want to believe in one number (once the mythical “MIPS” rating), we’ve (mostly) fixed that over the last 20 years. Good performance engineers have always given relative performance ranges and said YMMV (Your Mileage May Vary). 3) Mechanical engineers This, I expect, varies. In some cases, closed-form equations work pretty well. In other cases, one is using big structural dynamics and computational fluid dynamics codes to obtain “good-enough” approximations to reality before actually building something. For example, automobiles are extensively modeled via “crash codes”. 4) Petroleum engineers It’s been a while, but certainly, people who do seismic analysis and reservoir modeling *start* with data from the real world, analyze it to make decisions, so ought to be a little more accustomed to probabilistic analyses. 5) Financial engineers (Google: financial engineering) Not having physics to constrain simulations yields some wild results, although at least, some people are very comfortable with risk, uncertainty, and ensemble projections. I especially like Sam Savage’s Flaw of Averages”. On the other hand, when Nobel Economists lose $B (LTCM), I’m not surprised there is skepticism about climate models. 4. CONCLUSIONS That’s a speculative start. I do *not* think lumping a large group together as “senior engineers” helps progress, because I have at least anecdotal evidence that the sources of skepticism tend to be attached to the kinds of models and (maybe) simulations that someone does day-by-day. The problem is that many people tend to generalize from their discipline to others, and especially if they have trouble getting useful models, they tend to be suspicious of others’. At one extreme, people have long-established mathematical proofs, and answers that are clearly right or wrong. At the other extreme, people have to make decisions based on the best approximations they can get, and if their discipline has good-enough approximations, they tend to think one way, and if the approximations aren’t so good, they may think another about equations and climate models. ]] Since both 2 and 3 apply personally I can relate.
129675. Quietman at 14:54 PM on 9 October 2008
        Climate sensitivity is low
        Patrick William Collins, Robert Colman, James Haywood, Martin R. Manning and Philip Mote" "Drivers of Climate Change Atmospheric concentrations of many gases—primarily carbon dioxide, methane, nitrous oxide and halocarbons (gases once used widely as refrigerants and spray propellants)—have increased because of human activities." True IF based on high sensitivity.
129676. Quietman at 14:37 PM on 9 October 2008
        It's the sun
        chris As you are aware, I don't think the warming is from the sun alone, anymore than from GHGs. I made my arguments in the volcanos thread so I won't put an argument here.
129677. Adamski at 13:19 PM on 9 October 2008
        Climate's changed before
        Has any research been done on just how much water vapour can be held in the atmosphere and the warmer temperatures before it reaches saturation point? And also explain to me why Douglas Hoyt's info is so dodgy. He's fairly knowledgeable in the field so why is his contribution so wrong? How do we know what's right or wrong? You can justify comments with 'scientific proof' but how do we know that it is correct? Are you prepared to take anyones word for it? Is there some corruption not only from the climate change skeptics but also from the IPCC and other anthropogenic climate change supporters? It's all very interesting but doesn't everyone within this current issue have an agenda?
129678. chris at 08:06 AM on 9 October 2008
        Is Antarctic ice melting or growing?
        Re #5 DB2/#6 Quietman Those assumptions (warmer = more humid....or warm + humid + CO2 = more plant growth) unfortunately do not survive real world analysis/observation. As the earth warms, the atmosphere supports raised water vapour concentrations. What effect does this have on precipitation patterns? It would be wonderful to think that this will have beneficial effects on agricultural production (for example). Sadly, that's already being shown not to be the case. While global warming is resulting in enhanced atmospheric water vapour concentrations as predicted by theory/models, this doesn't translate into useful enhancement of rainfall. In fact the effect on rainfall patterns is pretty much exactly what we don't want. This has been analyzed recently in studies of warming-induced variation of precipitation. In esssence, just as models predict, those regions of the earth that have limited water supply, have a REDUCTION of precipitation (the equatorial regions between around 0 - 30 o N), whereas those regions that have generally useful or abundant precipitation, will have to cope with enhanced precipitation. That's already happening, even 'though global warming is rather in its incipient stages so far: Zhang XB (2007) "Detection of human influence on twentieth-century precipitation trends" Nature 448, 461-465. Abstract: "Human influence on climate has been detected in surface air temperature(1-5), sea level pressure(6), free atmospheric temperature(7), tropopause height(8) and ocean heat content(9). Human-induced changes have not, however, previously been detected in precipitation at the global scale(10-12), partly because changes in precipitation in different regions cancel each other out and thereby reduce the strength of the global average signal(13-19). Models suggest that anthropogenic forcing should have caused a small increase in global mean precipitation and a latitudinal redistribution of precipitation, increasing precipitation at high latitudes, decreasing precipitation at sub-tropical latitudes(15,18,19), and possibly changing the distribution of precipitation within the tropics by shifting the position of the Intertropical Convergence Zone(20). Here we compare observed changes in land precipitation during the twentieth century averaged over latitudinal bands with changes simulated by fourteen climate models. We show that anthropogenic forcing has had a detectable influence on observed changes in average precipitation within latitudinal bands, and that these changes cannot be explained by internal climate variability or natural forcing. We estimate that anthropogenic forcing contributed significantly to observed increases in precipitation in the Northern Hemisphere mid-latitudes, drying in the Northern Hemisphere subtropics and tropics, and moistening in the Southern Hemisphere subtropics and deep tropics. The observed changes, which are larger than estimated from model simulations, may have already had significant effects on ecosystems, agriculture and human health in regions that are sensitive to changes in precipitation, such as the Sahel." Allan, R P & Soden, B J (2008) Atmospheric warming and the amplification of precipitation extremes" Science 321, 1481-1484. Abstract: "Climate models suggest that extreme precipitation events will become more common in an anthropogenically warmed climate. However, observational limitations have hindered a direct evaluation of model- projected changes in extreme precipitation. We used satellite observations and model simulations to examine the response of tropical precipitation events to naturally driven changes in surface temperature and atmospheric moisture content. These observations reveal a distinct link between rainfall extremes and temperature, with heavy rain events increasing during warm periods and decreasing during cold periods. Furthermore, the observed amplification of rainfall extremes is found to be larger than that predicted by models, implying that projections of future changes in rainfall extremes in response to anthropogenic global warming may be underestimated." And of course the notion that enhanced warming and raised CO2 levels is "good" for plant growth is also a fallacy when translated into the real world especially with respect to agricultural production. What happens in controlled greenhouse experiments under conditions of optimal nutrient supply and careful temperature/hydrological control, doesn't translate into the real world. Despite enhanced atmospheric CO2 and "raised" world wide humidity, it's predicted that Southern Africa will lose around 30% of its staple crop (maize) in the next 20 years...Southern Asia will have substantially reduced yields of rice, millet and maize and so on. These effects relate to the predicted and observed REDUCED precipitation/raised temperature in the low latitude equatorial belt in a warming world, already underway as described above: David B. Lobell et al. (2008) "Prioritizing Climate Change Adaptation Needs for Food Security in 2030" Science 319, 607-610. Abstract: "Investments aimed at improving agricultural adaptation to climate change inevitably favor some crops and regions over others. An analysis of climate risks for crops in 12 food-insecure regions was conducted to identify adaptation priorities, based on statistical crop models and climate projections for 2030 from 20 general circulation models. Results indicate South Asia and Southern Africa as two regions that, without sufficient adaptation measures, will likely suffer negative impacts on several crops that are important to large food-insecure human populations. We also find that uncertainties vary widely by crop, and therefore priorities will depend on the risk attitudes of investment institutions." Sadly, life and the real world isn't accommodating of simplistic hopeful predicted consequences. A warming world is not a world with enhanced prospects for either agricultural production, or a reduction in sea level rise due to enhanced snow deposition at the poles. The expectation is that sea levels are going to rise and agricultural production is going to decrease as the earth continues to warm. We'll have to work very hard, and at great expense to adapt. Those people least equipped to do so will (as usual) bear the brunt of the hardships....
129679. chris at 00:27 AM on 9 October 2008
        CO2 measurements are suspect
        Re #1 That really doesn't make much sense Mizimi. Since the atmosphere is a relatively well-mixed medium, one doesn't need a whole network of sites measuring CO2 to obtain a pretty accurate measure of global atmospheric CO2 concentrations. It's not like a temperature measurement which is a highly local parameter, even if this may be correlated with temperature measurements up to quite a large distance away. Again this is straightforward to demonstrate. For example if you click on John's link above to the NOAA site you will see that the Manua Loa CO2 measurements and the globally averaged sea surface measures match very closely (within around 1 ppm). Even comparing Northern hemisphere and S hemisphere averages, the numbers are pretty similar, especially when averaged over a year. What's fascinating about your post is that on another thread ("It's the sun"), you promote the awesomely inept analysis of paleo CO2 measures of a German school teacher (Mr Beck), who "finds" historical CO2 measures that jump up and down wildly (100 ppm in a few years!). Now if one actually examines the original papers from which Beck's weird analysis descends, you find a bunch of wildly unrepresentative CO2 measurements made in cities. We know these give false measures of the globally averaged atmospheric CO2 levels since the scientists who made them point out, for example, that CO2 measures are 40 ppm higher in the afternoon than in the morning, and higher on windless days compared to windy days. These are clear indications of massive contamination of CO2 measures with industrial/human sources (see my post #172 on the "It's the sun" thread). So on the one hand you are cheerleading for awesomely nonsensical paleoCO2 data massively contaminated with urban/industrial contributions... ...and on the other (here), asserting that the atmospheric CO2 data "cannot represent the global condition" when in fact it's easy to demonstrate that they do represent the global condition, since data from urban centres isn't used in assessing the atmospheric CO2 concentrations ('though they might have other uses with respect to local conditions). One needs to decide whether one is being skeptical or is instead pursuing conspiracy theories on behalf of dodgy agendas!
129680. Patrick 027 at 16:24 PM on 8 October 2008
        Climate sensitivity is low
        

        Some general info: "The Physical Science behind Climate Change Why are climatologists so highly confident that human activities are dangerously warming Earth? Members of the IPCC, the 2007 peace winner, write on climate change By William Collins, Robert Colman, James Haywood, Martin R. Manning and Philip Mote" link  "Simple Question, Simple Answer… Not" Real Climate, I have comments here (numbers of comments that were mine:) Real Climate (11,86,98,109,132,138,141) Real Climate (104,105,111) Real Climate (59,123,147,152,153,159,160,171,175,189,193,195,197,218,234,236,239,251,257,265,266,267,268(repeated an error regarding $700 billion, oops!),271,273,285,294, NOTE ALSO these comments that are not mine: 102,226 and the the responses to 81,166,201) Real Climate (9,10,11,49,50,60,138,142,161,166,170,171,175) HERE IS THE COMMENT ON THERMODYNAMICS (and some other comments): Real Climate (69,73,74,75)

        Moderator Response:

        [RH] Fixed links that were breaking page format.

129681. Patrick 027 at 11:27 AM on 8 October 2008
        Climate sensitivity is low
        Response to comment 62 (Quietman) in "It's volcanoes (or lack thereof)": "You still assume AGW is a big player and I do not. See the sensitivity thread. " No, I don't assume, I conclude. There isn't much more I could say about that, after: http://blogs.abcnews.com/scienceandsociety/2008/07/tropical-storm.html http://blogs.abcnews.com/scienceandsociety/2008/07/global-warming.html#comments http://blogs.abcnews.com/scienceandsociety/2008/09/nature-is-not-a.html (PS in the first of those, before I realized "Science and Society" deletes website addresses, I had posted some links to some RealClimate posts where I had some comments. Might go back and repost those RealClimate sites here later... I remember one was about basic thermodynamics.) Relavant to climate sensitivity and time constants, I had made some comments in the last of those three "Science and Society" sites above, where it was found: For a linearized approximation of climate behavior, in terms of global average surface temperature, with constant effective heat capacity and climate sensitivity: If the time constant is also the e-folding time for exponential decay to equilibrium (that's my understanding of the term 'time constant'): Time constant (or e-folding time) = heat capacity (average per unit area) * climate sensitivity. For example, for a climate sensitivity of 0.7 K/(W/m2) and the globally-averaged effect of the heat capacity of the top 100 m of ocean, I found an e-folding time of about 6 years. From this website, the time constant may be more like 15 years or so (for a prolonged climate forcing change, which can then penetrate below the top of the ocean), so with the same climate sensitivity, the effect heat capacity may be more like that of the top ~ 250 m of ocean (but this is only a mathematical equivalence - the warming signal would penetrate more or less deeply at different locations depending on the circulation patterns). If it turns out that 1. solar effects outside of TSI(multiplied by 0.7/4 to get climate forcing) and enhanced solar UV (I'm assuming that's taken into account in at least some models, since it is understood that a greater portion of solar variation is in UV and UV affects the upper atmosphere (stratosphere, etc.) in particular), such as magnetic effects and solar wind, 2. variations in ocean tidal forcing, it's effect on ocean circulation and mixing. 3. geomagnetic changes outside of effects of solar changes on magnetosphere 4. volcanism or whatever ... if any of these turns out to have been more important than previously judged, the conclusion would not be that AGW is not important but that the climate forcing has been bigger than it was thought and so the climate sensitivity must not be as great - OR perhaps the climate sensivity is what we thought but we have underestimated the cooling effect of our aerosol emissions... Etc. PS of 1-4 above, ... well I'm skeptical. I'm interested in learning more about 1-3, though, although I'm doubtful of the effectiveness of proposed mechanisms for 1 and 3 (though there was one article you had mentioned some time ago that looked intriguing... about variations in transmissivity of clear sky atmosphere due to electromagnetic/ionospherice/solar wind/related stuff...); for 2, I'm doubtful as to the strength of the variations over the time periods pertinent to AGW (and not clear that it was really asserted that 2 would account for some significant portion of what has been attributed to AGW forcing)
129682. Patrick 027 at 10:47 AM on 8 October 2008
        Volcanoes emit more CO2 than humans
        ... will post response at: http://www.skepticalscience.com/climate-sensitivity.htm
129683. chris at 07:10 AM on 8 October 2008
        Human CO2 is a tiny % of CO2 emissions
        Re #10 Mizimi That's a massive non-sequiter unfortunately. It also contains an essential fallacy. The 90% of the Earth's sequestered carbon ISN'T "locked up in ocean sediments"...90% of the earth's sequestered carbon was originally DERIVED from ocean sediments (and is now oil/natural gas and so on...) Of course we know very well that the evidence indicates that the system described in the graphics in the top article is more or less in balance. This refers to the short term carbon cycle which describes the recycling of non-sequestered carbon through the biosphere, as well as some elements of the longer term carbon cycle involving slow sequestration of carbon and its reintroduction to the biosphere through (largely) ocean sedimentation of carbon fixing life-forms and volcanic activity, respectively. This is readily apparent in the paleoCO2 record. In the short term (last 10000 years), atmospheric CO2 has maintained a relatively steady CO2 concentration (270 ppm +/- 10 ppm)... e.g. http://www.ipcc.ch/pdf/assessment-report/ar4/wg1/ar4-wg1-spm.pdf lower resolution data indicate that this sort of level has been in the atmosphere for the last 20-odd million years before the 20th century (i.e. 180-350 ppm; the low values occurring during glacial periods). e.g. Pearson, PN and Palmer, MR (2000) "Atmospheric carbon dioxide concentrations over the past 60 million years" Nature 406, 695-699. So that equilibrium in the short/medium term carbon cycle exists and is readily apparent. Obviously once one starts digging up and burning carbon sequestered out of the cycle for many 10's and 100's of millions of years, the equilibrium is abruptly perturbed, and as we're seeing atmospheric CO2 levels are shooting upwards. Incidentally, which "other factors" that are being "totally ignored" were you thinking of Mizimi?
129684. chris at 05:24 AM on 8 October 2008
        It's the sun
        ..sorry I meant the 9th warmest Jan-August on record. best to be accurate!
129685. chris at 05:21 AM on 8 October 2008
        It's the sun
        Re #176 Quietman Truthseeker considered that it was relevant since he (she?)bothered to write a post about it. The data from the NOAA site just wasn't related very well (perhaps Truthseeker isn't really a truth seeker!). Of course (as I said in my post) one can't assess trends by examining single months. Perhaps the relevance relates to those drip drip efforts to downplay the effects of global warming! Or perhaps the relevance is that in a year that doesn't "seem" that warm, where we've had the effects of a strong La Nina at the start of the year, and we are additionally smack at the bottom of the solar cycle (remember that the Tung and Camp paper that you have been cheerleading supposedly gives us a 0.2 oC of cooling at the solar minimum compared to the maximum), we've had the 10th warmest Jan-August on record... ...that's pretty remarkable! ...or perhaps not.....
129686. chris at 05:11 AM on 8 October 2008
        CO2 lags temperature
        Well that's good Quietman....you don't have a problem with some of the simple expectations of CO2 feedbacks as they apply under the influence of Milankovitch cycles. On the other hand it's not obvious why you consider a truism to be an assumption! It's been known since the middle of the 19th century that the earth's temperature is defined by the insolation from the sun (which gives the Earth a black body temperature near -15 oC) and the greenhouse effect arising largely from water vapour and CO2 that supplements the black body temperature by around 30 oC. That's pretty much a truism. One cannot pretend that the greenhouse effect doesn't exist! So the solar and greenhouse contributions effectively set the earth's equilibrium temperature, and stochastic and cyclical variations in the climate system (wind and ocean currents) and volcanic effects, give rise to fluctuations around the equilibrium temperature. Occasionally rather horrible impacts from extraterrestrial sources or catastrophic tectonic events generate major abrupt perturbations. But otherwise it's the sun and the greenhouse effect. ...and indeed the major independent variable with respect to the greenhouse effect is the atmnospheric CO2 (and methane somewhat, especially in the deep past) concentration, since as we all know very well, atmospheric water vapour concentrations rather passively follow the atmospheric temperature (and pressure). What did you have in mind?
129687. Quietman at 03:55 AM on 8 October 2008
        It's the sun
        Re: "6th coolest in the last 30 years vs 10th warmest in the global surface record out of 129 years" Does this have any relevance whatsoever?
129688. Quietman at 03:48 AM on 8 October 2008
        CO2 lags temperature
        Re: "Another way of thinking about this is to recognisie the truism that the earth's equilibrium temperature will fluctuate (by internal variations of the climate system) around a level that is "set" by whatever level of greenhouse gas concentrations and insolation that happens to pertain." ASSUMPTION!!!
129689. Quietman at 03:46 AM on 8 October 2008
        CO2 lags temperature
        Re: "It's a question of relative magnitudes of forcings, and the timescales for various re-equilibration to changes in forcings" YES!!!
129690. Quietman at 03:45 AM on 8 October 2008
        CO2 lags temperature
        Re: "But isn't that exactly what's expected if the CO2 rise and fall is itself a feedback from the primary (Milnkovitch-induced) warming? " YES!!!
129691. chris at 01:16 AM on 8 October 2008
        It's the sun
        Three problems wth that Truthseeker: (i) one can't presume trends by looking at data from single months! (ii) I doubt anyone would have stated that the La Nina was the sole cause of a period of relative cooling in a warming world. We're smack at the bottom of the solar cycle, so one doesn't expect record breaking temperatures for a while (the next major El Nino in a few years is likely to give us the new record). (iii) Your interpretation seems somewhat odd anyway. From the data you've linked to we can see that: a. August 2008 is the 10th warmest in the global surface record out of 129 years. Clearly therefore there can only be 9 Augusts warmer than it in the last 30 years (not 24 as you intimate). b. June to August 2008 is the 9th warmest summer in the global surface record of 129 years. Clearly therefore there can only be 8 summers warmer than it in the last 30 years. c. and so on (it's the 9th warmest Jan-August period on record)
129692. chris at 00:56 AM on 8 October 2008
        CO2 lags temperature
        #32 and #43 You each dismiss the possibility of feedbacks to CO2-induced warming, without really explaining your problem. In each case this seems to relate to the observation that during Milankovitch cycles associated with glacial-interglacial-glacial transitions, the earth's temperature drops while atmospheric CO2 levels remain high for a while. But isn't that exactly what's expected if the CO2 rise and fall is itself a feedback from the primary (Milnkovitch-induced) warming? Obviously atmospheric CO2 levels will lag behind temperature levels on both the rising and falling parts of the cycle. It's a question of relative magnitudes of forcings, and the timescales for various re-equilibration to changes in forcings. If the solar (insolation) dominates (as we consider to be the case), then it will "dominate" the effects of CO2, feedbacks and all. We could make an analogy with the day night cycle. Right now atmospheric CO2 levels are the highest they've been for many millions of years and the Earth is warming. However last night while CO2 levels were extraordinarily high (382 ppm or whatever the current value is), when the sun went down, it got a bit cooler. In fact as the air cooled last night some of the water vapour precipitated out and it rained.... Now that scenario doesn't indicate that raised atmospheric CO2 doesn't have an associated positive water vapour feedback. It clearly does (we can measure this in the real world). It just means that the insolation effect dominates the CO2 effect, feedbacks and all. The associated thing that needs to be considered is the timescale of the effects. The CO2 feedback to warming is very slow (and likewise to cooling). Once atmospheric CO2 levels are raised they stay that way for a long time. But both the warming effect of CO2 and its water vapour feedback are a consequence of an interaction with the insolation. If the insolation drops, then the greenhouse effect of the raised CO2 and water vapour will drop immediately. And a reduction in the feedbacks will follow on different timescales. The water vapour feedback will drop quickly (days to months following reduced warming resulting from reduced insolation)....the atmospheric CO2 levels will remain high for a very long time following the temperature drop and will drop much, much more slowly in response to the cooling. In fact in the cooling part of the cycle the secondary feedback on the warming cycle (water vapour following the CO2 rise) will seem to reduce much more quickly than the primary feedback (the raised atmospheric CO2). Another way of thinking about this is to recognisie the truism that the earth's equilibrium temperature will fluctuate (by internal variations of the climate system) around a level that is "set" by whatever level of greenhouse gas concentrations and insolation that happens to pertain. However the rates at which these equilibria are attained depends on the rates at which various feedbacks respond. So what might seem to be anomalous phenomena, are not unexpected at all....
129693. TruthSeeker at 00:24 AM on 8 October 2008
        It's the sun
        For thoes of you who said that recent cooling was due to la Nina and that the trend would end in the second half of the year. Take a look at this NOAA data, it tends to prove you wrong. It looks like this August is the 6th coolest in the last 30 years. http://www.ncdc.noaa.gov/oa/climate/research/2008/aug/global.html#year-to-date
129694. chris at 21:26 PM on 7 October 2008
        Climate sensitivity is low
        Re #2 GMB You've got that wrong. Schwartz is the one that is using very short time series (largely 40-50 year periods in the 20th century) to estimate his "sensitivity". Your comments about CO2 and its relation to temperature change during ice age cycle transitions are not relevant in the manner that you might wish your capitalized phrase to insinuate. There are two essential methods of determining climate sensitivity in relation to real world measurements (a third would be to use a completely theoretical analysis). These are: (i) Determination of the relationship between equilibrium temperature and atmospheric CO2 from paleodata. This is in principle preferable since the analyis can be made with respect to "equilibrium" situations. i.e. since the climate sensitivity relates explicitly to the earth's surface temperature rise AT EQUILIBRIUM per doubling of atmospheric CO2, this should give us the more accurate analysis. Unfortunately there are uncertainties due to the uncertainties in the paleodata. (ii) The second is to eschew equilibrium measurements and monitor the temperature response to enhanced greenhouse forcing as the temperature rises TOWARDS it's new equilibrium temperature. Simplistically (and Schwartz has used this simplisitic approach) one considers that there will be a hyperbolic rise to a new equilibrium temperature. A regular hyperbola is characterized by its MAXIMUM VALUE at equilibrium (in this case the climate sensitivity) and a TIME CONSTANT that characterises the rate at which equilibrium is achieved. Obviously if the maximum (equilibrium) hasn't been reached one needs to estimate the parameters defining the "shape" of the response. Schwartz makes several errors and unrealistic asumptions that are outlined in some of the links in John's top post. He uses detrended time series of 20th century temperature trends, makes an unrealistic assumption that the climate system response can be characterised by a single exponential (one time constant), and comes up with a time constant of 5 years. Unfortunately his detrending smooths out the longer time constants that alomst certainly apply to the system. In essence he's attempting to pursue the conclusion that we've had much of the warming due to the increased forcing already. However if more realistic multiple time constant series are used (i.e. his data are heavily biased towards the very rapid time constant(s) for atmospheric warming in response, for example, to volcanic eruptions, the less rapid time constant for ocean surface warming and so on), his climate sensitivty value increase rather markedly. And since the oceans are a repository of thermal inertia limit a rapid re-equilibration of the earth's surface temperature, it's rather more valid to include long time constants when considering the EQUILIBRIUM response of the Earth's temperature to greenhouse warming. In fact if a rather more realistic time constant of 15 years is used, Schwartz's climate sensitivty becomes near 3 oC per doubling of atmospheric CO2, pretty much equivalent to all of the other published data. It's pretty clear from reading Schwartz's paper that he realises that his analysis is extremely oversimplified. I'm not sure what you consider to be the relevance of the fact that warming leads rising atmospheric CO2 during the glacial-interglacial transitions for this analysis. The aim of all of these analysis is to determine the best estimate of the climate sensitivity to rising atmospheric CO2 levels. The source of the rise in atmospheric CO2 is not really relevant for these analyses... PS: Having read what I've written before posting it, I realize I've said quite a bit of what John Cook has already said in his top article !
129695. Quietman at 19:03 PM on 7 October 2008
        Volcanoes emit more CO2 than humans
        Patrick You still assume AGW is a big player and I do not. See the sensitivity thread.
129696. chris at 10:59 AM on 7 October 2008
        Temp record is unreliable
        Re #30-32 These questions have been addressed fairly conclusively by the science. (i) You are correct (Tree) that the earth took many millions of years to sequester atmospheric CO2 in the form of fossil fuels (oil, gas, coal, shale and so on). Around 4000 billion tons of carbon is "stored" in this manner, and it's taken around 600 million years to do this. In the last 100 years we've released around 500 billion tons of this carbon back into the atmosphere, of which around 200 billion tons has remained there (around 300 billion tons has been absorbed by the oceans and terrestrial environment). see for example: http://www.physicalgeography.net/fundamentals/9r.html (ii) It's very clear that volcanic activity is on a miniscule scale with respect to our massive release of carbon dioxide. It's easy to demosstrate this. If one examines the high resolution atmospheric CO2 record over the last 1000 years, for example, one can see that the atmospheric CO2 levels remain rather constant over the period up to around the mid to late 19th century and rise massively in response to our emissions. The absence of significant activity from volcanoes can be observed by the absense of jumps in the atmospheric CO2 record as a result of the truly hummungous volcanoes of the last 1000 years (e.g. Santorini, Krakatoa and Tambora). Volcanic activity results in the release of something a ggod bit less than 1% of our current industrial emissions. see, for example, the high resolution atmospheric CO2 record compiled on page 3 of the IPCC summary for policymakers: http://www.ipcc.ch/pdf/assessment-report/ar4/wg1/ar4-wg1-spm.pdf (see page 3) (iii) Heat from tectonic activity is trivial with respec to greenhouse gas warming. This is one of those fallacious "arguments" that is doing the rounds! The practicioners avoid the three pertinent points. These are: (i) is there any evidence for enhanced tectonic activity during the period of very large warming (especially last 30-odd years)? After all tectonic activity has been occurring for millions of years. Has it suddenly intensified? Evidence please! (ii) how can it be that the areas of which major tectonic activity show little match to areas of temperature increase? For example Iceland is one of the most tectonically active regions on earth. However it is one of the few places on earth that has undergone a tiny bit of COOLING during the period of global warming: e.g. data on the scale and location of Arctic warming over the last 50 years from the Colorado University Arctic research center: http://arctic.atmos.uiuc.edu/CLIMATESUMMARY/2003/IMAGES/annual.1954-2003.tchange.png (iii) the heat released by undersea tectonic activity is around that of the geothermal background. This is around 0.1% of the heat energy from solar/greenhouse activity. e.g. according to Jeff Severinghaus of the Scripps Institution of Oceanography "... the average heat added from volcanoes to the ocean is of order 0.1 Watt per square meter. But the heat added (or removed) to the ocean from the sun and atmosphere is of order 100 Watt per square meter. So it is very hard for volcanoes to compete." So it's not just a question of showing that tectonic activity on the ocean bottom is significant with respect to warming (the evidence indicates it isn't), but of showing that this activity has increased in the last several decades to an extent that can have contributed to warming (the evidence indicates that it hasn't)...
129697. chris at 09:48 AM on 7 October 2008
        It's the sun
        Re #160 Wondering Aloud You state rather cryptically that "The satellite data that was supposed to prove a positive feedback from CO2 causing increased water vapor in fact show the opposite." but that doesn't seem to accord with the facts. The expectation is that as the atmosphere warms, the air will support somewhat higher levels of water vapour (since warm air has a higher saturation point for water vapour than colder air). This results in a feedback warming due to the greenhouse properties of atmospheric water vapour. So has the water vapour concentration increased during the period of massive increase in atmospheric CO2, in response to CO2-driven warming? According to the science the answer seems to be yes (as opposed to your unattributed "no"): Soden BJ et al. (2005) "The radiative signature of upper tropospheric moistening" Science 310, 841-844. Abstract: "Climate models predict that the concentration of water vapor in the upper troposphere could double by the end of the century as a result of increases in greenhouse gases. Such moistening plays a key role in amplifying the rate at which the climate warms in response to anthropogenic activities, but has been difficult to detect because of deficiencies in conventional observing systems. We use satellite measurements to highlight a distinct radiative signature of upper tropospheric moistening over the period 1982 to 2004. The observed moistening is accurately captured by climate model simulations and lends further credence to model projections of future global warming." Santer BD et al (2007) "Identification of human-induced changes in atmospheric moisture content" Proc. Natl. Acad. Sci. USA 104 15248-15253. Abstract: "Data from the satellite-based Special Sensor Microwave Imager (SSM/I) show that the total atmospheric moisture content over oceans has increased by 0.41 kg/m(2) per decade since 1988. Results from current climate models indicate that water vapor increases of this magnitude cannot be explained by climate noise alone. In a formal detection and attribution analysis using the pooled results from 22 different climate models, the simulated "fingerprint" pattern of anthropogenically caused changes in water vapor is identifiable with high statistical confidence in the SSM/I data. Experiments in which forcing factors are varied individually suggest that this fingerprint "match" is primarily due to human caused increases in greenhouse gases and not to solar forcing or recovery from the eruption of Mount Pinatubo. Our findings provide preliminary evidence of an emerging anthropogenic signal in the moisture content of earth's atmosphere." Rind D et al (1991) "Positive Water-Vapor Feedback In Climate Models Confirmed By Satellite Data" Nature 349, 500-503. Abstract: "Chief among the mechanisms thought to amplify the global climate response to increased concentrations of trace gases is the atmospheric water vapour feedback. As the oceans and atmosphere warm, there is increased evaporation, and it has been generally thought that the additional moisture then adds to the greenhouse effect by trapping more infrared radiation. Recently, it has been suggested that general circulation models used for evaluating climate change overestimate this response, and that increased convection in a warmer climate would actually dry the middle and upper troposphere by means of associated compensatory subsidence1. We use some new satellite-generated water vapour data to investigate this question. From a comparison of summer and winter moisture values in regions of the middle and upper troposphere that have previously been difficult to observe with confidence, we find that, as the hemispheres warm, increased convection leads to increased water vapour above 500 mbar in approximate quantitative agreement with the results from current climate models. The same conclusion is reached by comparing the tropical western and eastern Pacific regions. Thus, we conclude that the water vapour feedback is not overestimated in models and should amplify the climate response to increased trace-gas concentrations." Allan RP and Soden BJ (2008) "Atmospheric warming and the amplification of precipitation extremes" Science 321, 1481-1484. Abstract: "Climate models suggest that extreme precipitation events will become more common in an anthropogenically warmed climate. However, observational limitations have hindered a direct evaluation of model- projected changes in extreme precipitation. We used satellite observations and model simulations to examine the response of tropical precipitation events to naturally driven changes in surface temperature and atmospheric moisture content. These observations reveal a distinct link between rainfall extremes and temperature, with heavy rain events increasing during warm periods and decreasing during cold periods. Furthermore, the observed amplification of rainfall extremes is found to be larger than that predicted by models, implying that projections of future changes in rainfall extremes in response to anthropogenic global warming may be underestimated." Note that this effect (atmospheric temperature-induced feedback in atmospheric water vapour concentrations) can also be observed as a result of atmospheric cooling, for example due to rapid volcanic eruption-induced cooling: Soden BJ et al. (2002) "Global cooling after the eruption of Mount Pinatubo: A test of climate feedback by water vapor" Science 296,727-730 Abstract: "The sensitivity of Earth's climate to an external radiative forcing depends critically on the response of water vapor. We use the global cooling and drying of the atmosphere that was observed after the eruption of Mount Pinatubo to test model predictions of the climate feedback from water vapor. Here, we first highlight the success of the model in reproducing the observed drying after the volcanic eruption. Then, by comparing model simulations with and without water vapor feedback, we demonstrate the importance of the atmospheric drying in amplifying the temperature change and show that, without the strong positive feedback from water vapor, the model is unable to reproduce the observed cooling. These results provide quantitative evidence of the reliability of water vapor feedback in current climate models, which is crucial to their use for global warming projections." and so on....
129698. chris at 09:28 AM on 7 October 2008
        It's the sun
        Re #160 Wondering Aloud (and many others) This thread shows a breathtaking absence of skepticism! It's rather awesome the nonsense that some people are willing to swallow in pursuit of a conspiracy theory. Let's look at the "paleorecord" ("water vapour feedback" in following post) THE PALEORECORD for CO2: The scientific analysis of paleoCO2 measurements and paleotemperature measurements are highlighted in numerous reviews and articles that are appended at the bottom of the post. These show a rather strong coupling of paleoCO2 and paleotemperature. Some posters are exercised over historical records described by a German schoolteacher (Beck). They apparently show CO2 measurements that go up and down in an extraordinary manner. Mr Beck assures us of the precision of historical measures of CO2 during the last 180 years. Why might we be skeptical of this weird data with its absolutely massive rapid jumps and falls in CO2? Here's some pretty obvious reasons for skepticism: (i) Beck assures us that the measures were precise (1-3%). But we're really more interested in their ACCURACY with respect to global atmospheric CO2 concentrations. We know that a large proportion of the measurements were made in individual scientists laboratories in cities (Paris, Kew gardens London, Belfast, Clermont Ferrand, Copenhagen, Vienna, Frankfurt, Giessen, Bern, Poona India, Rostock in Denmark, Ames Iowa...etc. etc. etc.). We know that if one goes to a city today and makes CO2 measurements in the air in our city laboratories, large variations in CO2 levels will be recorded, with high values relative to the true atmospheric concentrations. Just as in the 19th and early 20th century, we’re surrounded in cities by CO2 sources (pretty much all transport and heat/cooling generation). See for example point (iii) below. Competent scientists understand the essential difference between PRECISION and ACCURACY. A local CO2 measure may be beautifully precise but wildly inaccurate with respect to the global atmospheric CO2 value. That's where Becks "analysis" is likely to fool the unskeptical. (ii) We can look at this problem of accuracy in more detail by focusing on the individual series of measurements highlighted by Beck. For example, Beck highlights W. Kreutz’s series of very high CO2 measures in 1939/40. These measurements were made just S of the city of Giessen not far from the railway station. Beck fails to point out that Kreutz’s values differ by an astonishing 40 ppm between morning and afternoon (in other words measured atmospheric CO2 values are 40 ppm higher in the afternoons compared to the mornings), that atmospheric CO2 is much lower on windy days compared to windless days and so on. This is all outlined in Kreutz’s paper on the subject (translation available here: http://www.biokurs.de/treibhaus/literatur/kreutz/Kreutz_english.pdf). Clearly atmospheric CO2 measurements in, or near, urban centres give massively high CO2 values however precisely they are measured, the CO2 levels will rise dramatically in the afternoons when everyone and their machines are active, and on windless days when generated CO2 isn’t dispersed, measured CO2 levels will be higher still. That’s all pretty obvious. A skeptic might be expected to notice these rather obvious facts…. It's fascinating that Kreutz identified and postulated that some of the high values and extreme variations in atmospheric CO2 levels in his measurements were due to soil sources and industrial sources...sadly, and rather typically, the data of the honest and comptetent Kreutz has been usurped to support a creepy agenda by the dishonest... (iii) It takes an effort to make truly accurate and unperturbed atmospheric CO2 measurements. Some early practitioners made this effort. Jules Reiset, for example, in the late 19th century, developed a methodology for CO2 measurements taken on the windy Atlantic coast, far from urban centres, and determined values rather similar to those measured in contemporaneous ice cores (around 190-200 ppm in the 1890’s). We can be rather more confident in the ACCURACY of Reiset’s measurements since he (unlike pretty much all other measurers of CO2 in the 19th and early 20th century) identified the clear signature of seasonal variation due to plant growth and decay dominated by the N. hemisphere flora. (iv) We have been observing atmospheric CO2 levels with extraordinary precision and accuracy since the late 1950’s from the Manua Loa observatory, as well as dozens of other locations around the world. Atmospheric CO2 levels simply do not undergo massive jumps of up to 100 ppm over a few years. It beggers belief that CO2 sources could release and reabsorb extraordinarily massive amounts of CO2 (see #4 just below) during a period when we weren’t actually monitoring CO2 levels very well, and yet just when we started to monitor levels with considerable ACCURACY and PRECISION, atmospheric levels immediately stopped jumping around wildly. A skeptic would be inclined to doubt the accuracy of early measurements from urban centres. (v) According to Beck atmospheric CO2 rose and fell with massive jumps/falls of around 100 ppm or more during the early and mid 19th century, and the 1930’s-40s’. Since the pre-industrial level of atmospheric CO2 (around 180 ppm) is rather similar to the entire repository of CO2 in terrestrial plantlife, the assumption is that these 100 ppm jumps/falls over a few years are associated with the rapid loss and regrowth of around half the entire plant biomass on earth? Did we really lose terrestrial plant matter equivalent to the entire Amazon and African rainforests and much of Asia during a few short years, and have these regrow again in a few years afterwards? No. We know this can’t have happened during the 1930’s and 40’s since we were monitoring the terrestrial biosphere already during these years. (vi) we have rather abundant ice core measures of atmospheric CO2. Since these measures of atmospheric CO2 locked within ice are in regions far from centres of CO2 sources (urban/plant growth) they are rather reliable measures of unperturbed and well-mixed atmospheric CO2. These show rather constant levels of atmospheric CO2 near 177 (+/- around 6 ppm) during the period from 1000 AD to the mid 19th century, and then slow gradual rises that merge in the late 1950’s with the directly measured Manua Loa and other modern CO2 measures. One can certainly argue that the ice core measures are averaged, since deposited snow in ice sheets doesn’t compact and trap ice for several years after deposition, such that there is exchange with the atmosphere for some time until the atmospheric sample becomes sealed within bubbles in solid ice. However one can’t really postulate massive rise of atmospheric CO2 apparently to value as high as 470 ppm during the late 1930’s and 1940’s, without some rising of ice core CO2 levels that match this time period. Even if the ice core CO2 values are averaged over several years, high CO2 values would have to appear for this period in the ice cores. They don’t. and so on…. ---------------------------------------------- Here's some of the abundant data that indicates a rather close coupling of paleoCO2 and paleotemperature measurements right through the last 500 million years. D.L. Royer (2006) "CO2-forced climate thresholds during the Phanerozoic" Geochim. Cosmochim. Acta 70, 5665-5675. (this is a review compiles much of the published data) Even 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.
129699. chris at 05:21 AM on 7 October 2008
        Solar cycles cause global warming
        Re #3 That's incorrect. Tung and Camp derive a value for the earth's climate sensitivity to raised CO2 that is completely independent of the so-called "IPCC's accepted sensitivity". That's the whole point of their work! They analyze the solar cycle contribution to warming and (according to their analysis) derive an INDEPENDENT measure of the climate sensitivity. Their value is (see equation 2 on line 379 of their manuscript): 2.3 oK < DeltaT(2xCO2) < 4.1 oK In other words according to Tung and Camp, the Earth warms by around 3 oC (plus/minus a bit) for each doubling of atmospheric CO2 concentration. The fact that this value is pretty much in line with all of the other scientific analyses of climate sensitivity (as compiled by the IPCC) is interesting and may be taken as further evidence of a consistent arrival at the climate sensitivity using a number of different methods. But it is an ENTIRELY INDEPENDENT measure and doesn't assume anything whatsoever about "the IPCC"! That's pretty straightforward...
129700. TruthSeeker at 04:15 AM on 7 October 2008
        It's the sun
        You all said that the begining of the year was cooler due to la nina, and that this coolness trend would end July - August. However, August was cooler than the last few years via NOAA. Check the link: http://www.ncdc.noaa.gov/img/climate/research/2008/aug/glob-aug-pg.gif What do you all have to say about this?

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