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Post by Pooh on Jul 24, 2010 4:20:56 GMT
This Topic contains highlight notes from a reading of Johnston, Jason Scott, and Robert G. Fuller, Jr. Global Warming Advocacy Science: a Cross Examination. Research Paper. University Of Pennsylvania: University Of Pennsylvania Law School, May 2010. www.probeinternational.org/UPennCross.pdfSee the original report for references to scientific papers supporting statements in this research paper. Generally, my comments are italicized. The Table of Contents is copied here:solarcycle24com.proboards.com/index.cgi?action=display&board=talkanything&thread=1292&page=3#51517Summary of conclusions The IPCC and EPA assert that the human contribution to increased atmospheric carbon dioxide causes dangerous global temperatures, and therefore CO2 emissions are a pollutant under the definitions of the Clean Air Act. However, the temperature rise from a doubling of CO2 levels alone is about 1.5o C (e.g., average temperatures of Boston vs. New York City). The dangerous temperatures claimed to be caused by CO2 levels result from feedback (and coupling) assumptions in the IPCC’s computer models, not from a rise in CO2 itself.
There are deficiencies in IPCC models:- Aerosol assumptions are used as model tuning parameters
- Model inability to handle clouds and oceanic and atmospheric circulation
- Evidence of net Negative Feedback is ignored
- Alternative Human and Natural Effects ignored or suppressed
- Data has been manipulated and is suspect, but have been used to tune the models (via parameters)
- The IPCC association between CO2 and rising temperature has not been borne out (Carlin, 2009).
Therefore, if the feedback assumptions are incorrect, the models are deficient and the data were manipulated, then “Endangerment” does not exist. Adaptation may be desirable, but not mitigation such as Cap-And-Trade. Carlin, Alan. “Comments on Draft Technical Support Document for Endangerment Analysis for Greenhouse Gas Emissions under the Clean Air Act (Based on TSD Draft of March 9, 2009).” Scientific Blog. Carlin Economics and Science, March 16, 2009.www.carlineconomics.com/files/pdf/end_comments_7b1.pdf
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Post by Pooh on Jul 24, 2010 4:27:15 GMT
Abstract of Johnston and Fuller, 2010 (shortened for brevity)"Legal scholarship has come to accept as true the various pronouncements of the Intergovernmental Panel on Climate Change (IPCC) and other scientists who have been active in the movement for greenhouse gas (ghg) emission reductions to combat global warming.... "This paper departs from such faith in the climate establishment by comparing the picture of climate science presented by the Intergovernmental Panel on Climate Change (IPCC) and other global warming scientist advocates with the peer-edited scientific literature on climate change. A review of the peer-edited literature reveals a systematic tendency of the climate establishment to engage in a variety of stylized rhetorical techniques that seem to oversell what is actually known about climate change while concealing fundamental uncertainties and open questions regarding many of the key processes involved in climate change. ... "Insofar as establishment climate science has glossed over and minimized such fundamental questions and uncertainties in climate science, it has created widespread misimpressions that have serious consequences for optimal policy design."... You may wish to look up "Post-Normal Science". Here is a start: Ravetz, Jerome. “Climategate: Plausibility and the blogosphere in the post-normal age..” Scientific Blog. Watts Up With That?, February 9, 2010. wattsupwiththat.com/2010/02/09/climategate-plausibility-and-the-blogosphere-in-the-post-normal-age/#more-16262
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Post by Pooh on Jul 24, 2010 4:28:53 GMT
Page 06 Approach "My strategy in this paper is to adopt the approach that would be taken by a non-scientist attorney deposing global warming scientists serving as experts for the position that anthropogenic ghg emissions have caused recent global warming and must be halted if serious and seriously harmful future warming is to be prevented – what I have called above the established climate story. The established story has emerged not only from IPCC AR’s themselves, but from other work intended for general public consumption produced by scientists who are closely affiliated with and leaders in the IPCC process. Hence the cross-examination presented below compares what is said in IPCC publications and other similar work by leading climate establishment scientists with what is found in the peer-edited climate science literature. ... "Far from turning up empty, my cross examination has (initially, to my surprise) revealed that on virtually every major issue in climate change science, the IPCC AR’s and other summarizing work by leading climate establishment scientists have adopted various rhetorical strategies that seem to systematically conceal or minimize what appear to be fundamental scientific uncertainties or even disagreements. The bulk of this paper proceeds by cataloguing, and illustrating with concrete climate science examples, the various rhetorical techniques employed by the IPCC and other climate change scientist/advocates in an attempt to bolster their position, and to minimize or ignore conflicting scientific evidence."
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Post by Pooh on Jul 24, 2010 4:33:46 GMT
Page 07 Assumed Positive Feedbacks drive modeled temperature increases"As I discuss in more detail below, however, it is only because they presume that there are so many positive feedback effects that climate models get their large projected temperature increases – indeed without such positive feedbacks, climate models predict that a doubling of CO2 relative to the standard pre-industrial baseline would lead to only about a 1 degree centigrade increase in global temperature." Page 08, 09 Problems with temperature observations, predictions, feedback effects, climate sensitivity and impact of natural variability"When one looks at this decidedly mainstream literature, one discovers a number of facts and findings that seem not to well understood and which are rarely if ever even mentioned in the climate change law and policy literature: - There seem to be significant problems with the measurement of global surface temperatures over both the relatively short run – late 20th century – and longer run – past millennium – problems that systematically tend to cause an overestimation of late 20th century temperature increases relative to the past;
- Continuing scientific dispute exists over whether observations are confirming or disconfirming key short-run predictions of climate models – such as an increase in tropospheric water vapor and an increase in tropical tropospheric surface temperatures relative to tropical surface temperatures;
- Climate model projections of increases of global average surface temperature (due to a doubling of atmospheric CO2) above about 1 degree centigrade arise only because of positive feedback effects presumed by climate models;
- Yet there is evidence that both particular feedbacks -- such as that from clouds – and feedbacks in total may be negative, not positive;
- Confidence in climate models based on their ability to causally relate 20th century temperature trends to trends in CO2 may well be misplaced, because such models do not agree on the sensitivity of global climate to increases in CO2 and are able to explain 20th century temperature trends only by making arbitrary and widely varying assumptions about the net cooling impact of atmospheric aerosols;
- Similar reason for questioning climate models is provided by continuing scientific dispute over whether late 20th century warming may have been simply a natural climate cycle, or have been caused by solar variation, versus being caused by anthropogenic increases in atmospheric CO2;
- The scientific ability to predict what are perhaps the most widely publicized adverse impacts of global warming – sea level rise and species loss – is much less than generally perceived, and in the case of species loss, predictions are based on a methodology that a large number of biologists have severely criticized as invalid and as almost certain to lead to an overestimate of species loss due to global warming;
- Finally, many of the ongoing disputes in climate science boil down to disputes over the relative validity and reliability of different observational datasets, suggesting that the very new field of climate science does not yet have standardized observational datasets that would allow for definitive testing of theories and models against observations."
... "My cross examination clearly reveals a rhetoric of persuasion, of advocacy that prevails throughout establishment climate science."
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Post by Pooh on Jul 24, 2010 4:43:54 GMT
Page 21 Undisclosed uncertainties
"In terms of their policy significance, there are three even more important features of climate change models that are not commonly known and which climate scientists virtually never even mention in presentations or work intended for the more general public:
1) that although various positive feedbacks account for the high temperature increases that would generate large amounts of harm, so little is known about many of these feedback mechanisms that the most important positive feedbacks could actually be negative – cooling the planet – rather than enhancing warming;
2) climate models do not agree on how sensitive the climate is to increases in CO2 and manage to replicate twentieth century temperature trends only by inferring whatever aerosol cooling effect is necessary to “explain” observed temperatures; and,
3) the most concrete and therefore policy-relevant projections of climate change models, about what global warming will mean in particular regions of the world – hinge entirely upon predictions about how a warming climate will cause changes in global circulation patterns, but the models do not agree at all on how such circulation patterns will change."
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Post by Pooh on Jul 24, 2010 4:55:24 GMT
Page 29, 30 Global Circulation Model Parameters conflict
On tinkering with the parameters (esp. aerosols) to force the models to simulate 20th century "observations". Since the tinkering is unique to each model, there is no way to tell which climate sensitivity parameter is most accurate.
"As recent work has shown, if the (negative) aerosol forcing turns out to be much smaller than assumed, then the ensemble of GCM’s used by the IPCC would have to have a much larger climate sensitivity (with the mean moved up a full 2 degrees centigrade) in order to remain consistent with observations. On the other hand, if the negative aerosol forcing is even larger (more negative), then the ensemble GCM’s would fail on the other side, simulating too little warming. This “mismatch” between observed and simulated 20th century warming would mean that “current agreement between simulated and observed warming trends would be partly spurious, and indicate that we are missing something in the picture of causes and effects of large scale 20th century surface warming.”
Page 30 "That the models are essentially using aerosol parameterizations to offset variations in presumed climate sensitivity is far from an innocuous technical detail. As Richard Lindzen has explained, because a high climate sensitivity implies (other things equal) a big CO2 – induced warming, in order to have significant policy relevance climate models “cling” to high climate sensitivities, . And yet as just discussed here, the sensitivities are so high that the models simulate too much 20th century warming. To get a better reproduction of past temperatures, the models cancel out about half of simulated warming by imposing a compensating assumption about the cooling effect of aerosols. But then apparently to preserve “alarm” about the future, climate models assume that the aerosols will soon disappear. Even if the models are correct that aerosols have had a net cooling effect in the twentieth century, this series of parameter adjustments and assumptions about future changes in aerosols can hardly inspire confidence in climate models."
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Post by Pooh on Jul 24, 2010 5:01:13 GMT
(Page 30 Comment Re: "climate models assume that the aerosols will soon disappear")
See Aerosol Assumption Discussions at the end of these notes.
These trace the statement above to the effects of aerosols, particularly SO2, and to increased warming due to reduction of aerosols due to clean-air regulations.
Under "EPA contradicts itself", we see that while EPA regards CO2 as a driver of dangerous "Global Warming" under the Clean Air Act, the EPA will regulate the reduction of cooling SO2 under the Acid Rain program, thereby increasing "Global Warming".
Only a bureaucracy can have it both ways.
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Post by Pooh on Jul 24, 2010 5:07:52 GMT
Page 31 No correspondence between CO2 and climate?
"But over the Phanerozoic period as a whole, at least one long-term CO2 reconstruction finds “no correspondence” between atmospheric CO2 levels and global climate, while other studies find periods of up to 100 million years when high levels of CO2 were accompanied by cold temperatures in at least some regions of the world (indeed so many such periods that one review has characterized this finding as one of “perisistent Phanerozoic decorrelation” between tropical (low latitude) temperature and modeled CO2-induced radiative forcing).
Page 32 Faith or science?
"One should note how remarkable are these series of statements. After stating that scientists really have no idea how CO2 might have affected climate in the “widely varying configuration and states of the planet” that have prevailed over the past several hundred million years, Crowley and Berner then say that because extremely crude and imprecise proxy measures suggest a correlation between climate and CO2, we should continue to presume that CO2 played a role in causing climate change. Absent any other showing, this seems to be faith, not logic."
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Post by Pooh on Jul 24, 2010 5:12:37 GMT
Page 33, 34 Alternatives to IPCC theory suppressed
"In other words, their best guess is that an increase in CO2 did not cause warming in the period of deglaciation that they studied, but rather that an increase in the energy from the sun that caused the warming that eventually led to an increase in CO2.
"The 2007 paper by Stott et al. does not appear to be an outlier. Roughly contemporaneous work by Ahn and Brook constructed temperature and CO2 records covering both episodes of abrupt warming followed by cooling (Dansgaard-Oeschger events) and long separating cold periods (Heinrich events) that occurred during the last glacial. Ahn and Brook found a correlation between increases in CO2 and warming periods, but also found that unlike the large increases in methane that are known to have immediately preceded temperature increases, “CO2 does not lead temperature, [and] CO2 variations were not a direct trigger for the climate changes that occurred during the last glacial period.” Oddly, although the IPCC’s 2007 AR cites many articles that were published as late as 2007, neither the paper by Sott [sic] et al. nor that by Ahn and Brook are mentioned in the chapter on paleo-climatology in the 2007 AR."
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Post by Pooh on Jul 24, 2010 5:20:02 GMT
Page 34, 35, 36 The models do not handle water vapor and clouds well
A discussion of water vapor and its treatment in the climate models. Water vapor includes evaporation, precipitation, reflection of sunlight, and shade. The models do not handle water vapor and clouds well, according to the IPCC itself.
"Other things equal, the increase in humidity should lead to an increase in precipitation. At the same time, one might well expect an even bigger increase in precipitation, because warmer surface temperatures might well mean more evaporation, especially from the oceans and hence even more water vapor being put into a warmer atmosphere."
"Quite surprisingly, this is not what climate change models predict. The current set of coupled ocean-atmosphere GCM’s predict substantial increases in atmospheric water vapor (in the range of 7% per degree centigrade) as a consequence of CO2 forced temperature increases. ... The discrepancy between increases in precipitation predicted by climate models and what one would predict based on fundamental thermodynamic relations is in fact even greater than this because, as noted above, other things equal, evaporation should increase as the surface temperature warms."
"That is, to get the “muted response of precipitation to global warming” predicted by GCM’s “requires a decrease in global winds” brought about by changing global atmospheric circulation patterns. ... climate scientists have begun to collect data on atmospheric water vapor, wind and precipitation over large regions. And what they are finding is that at least on regional scales, water vapor, wind and precipitation are not moving in the direction predicted by GCM climate models." (Page 36)
"When Wentz et. al. looked at the variability of precipitation and evaporation over their study period, they found a “pronounced difference between the precipitation time series from the climate models and that from the satellite observations. Climate models under-predicted both the amplitude of interannual variability, decadal trends and the response to El Ninos by a factor of 2 to 3."
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Post by Pooh on Jul 24, 2010 5:26:44 GMT
Page 37 Observations and climate model predictions disagree
"Wentz et. al.’s conclusion is striking, for it certainly does not increase one’s confidence in the current generation of GCM models. As they present their summary interpretation, the most likely explanation for the discrepancy between observations and GCM predictions is that:
“the climate models have in common a compensating error in characterizing the radiative balance for the troposphere and the Earth’s surface. For example, variations in modeling cloud radiative forcing at the surface can have a relatively large effect on the precipitation response, whereas the temperature response is more driven by how clouds affect the radiation at the top of the atmosphere. …The difference between a subdued increase in rainfall and a C-C [Clausius-Clapeyron] increase has enormous impact, with respect to the consequences of global warming."
"Can the total water in the atmosphere increase by 15% with CO2 doubling but precipitation increase by only 4%? Will warming really bring a decrease in global winds? The observations here suggest otherwise…”
Also refers to studies by Wang and Paltridge et al. "More recently still, Paltridge et al. have looked at absolute and relative humidity tends over the period 1973-2007 at different altitudes and in both tropical and midlatitude zones and found little support for the constant relative humidity feature that is crucial to the large water vapor feedback effect in climate models. More precisely, climate models predict that even with surface and tropospheric warming, relative humidity at any given height in the troposphere remains roughly constant. Paltridge et al. find by contrast that for all the latitude zones that they studied, for all altitudes above the convective boundary layer, relative humidity “decreased over the past three or four decades as the surface and atmospheric temperatures have increased.”
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Post by Pooh on Jul 24, 2010 5:36:06 GMT
Page 38, 39 IPCC rebuttal to conclusions of observations
"Dessler and Sherwood argue that recent observations of a strong positive water vapor feedback from short term climate perturbations show that “the water vapor feedback is virtually certain to be strongly positive, with most evidence supporting a magnitude sufficient to roughly double the warming that would otherwise occur.”
"On the view maintained by Dessler and Sherwood and the IPCC, to generate “virtually certain” predictions of the large positive water vapor feedback that will result from an increase CO2, one doesn’t need to have an accurate model of how clouds and rainfall (involving “detailed microphysics and other small-scale processes”) will change with such an increase in water vapor."
Page 39, 40 Clouds and Rain Irrelevant? Really?
"The IPCC report explains in a succinct (if rather vague) way the two counteracting effects of cloud on surface temperature: “By reflecting solar radiation back to space (the albedo effect of clouds) and by trapping infrared radiation emitted by the surface and the lower troposphere (the greenhouse effect of clouds), clouds exert two competing effects on the Earth’s radiation budget. These two effects are usually referred to as the SW and LW components of the Cloud Radiative Forcing (CRF)….In the current climate, clouds exert a cooling effect on climate (the global mean CRF is negative).
The IPCC Report then admits quite quickly that clouds are quantitatively very significant in determining the earth’s radiative fluxes (or flows) and there is great uncertainty over how the balance between cloud cooling and cloud warming might be impacted by CO2- induced global warming:
“At the time of the TAR [the Third Assessment Report, issued in 2001], clouds remained a major source of uncertainty in the simulation of climate changes (as they still are at present: e.g. [various sections cited])…
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Post by Pooh on Jul 24, 2010 5:42:47 GMT
Page 41 Opinion"Were one approaching the climate change prediction problem for the first time, one might well conclude from the IPCC AR4’s own discussion that the GCM’s are probably wrong in assuming a positive cloud feedback, and that their projected temperature increases are consequently biased upward. Yet the Report’s discussion of clouds concludes by saying only that “…it is not yet possible to assess which of the model estimates of cloud feedback is the most reliable. However, progress has been made in the identification of the cloud types, the dynamical regimes and the regions of the globe responsible for the large spread of cloud feedback estimates among current models.” "b) The Peer-Reviewed Scientific Literature on Cloud Feedback "For quite some time, climate scientists have understood the basic mechanisms by which clouds affect climate. On the vertical dimension, high, cold cirrus clouds capture and reflect back longwave radiation, thus heating the earth’s surface and the atmosphere, an effect especially prominent at low latitudes, while (whereas) low, warmer clouds reflect solar shortwave radiation, thus cooling the earth’s surface and atmosphere, an effect that is especially likely at higher latitudes. Thus by tending to warm the tropical atmosphere and warm the polar atmosphere, “…clouds enhance the latitudinal gradient of column cooling and reinforce the meridional heating gradients responsible for forcing the mean meridional circulation of the atmosphere.”
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Post by Pooh on Jul 24, 2010 5:51:52 GMT
Page 42, 43 Graeme Stephens on the problems with modeled cloud feedback parameters (assumptions)."Importantly, as Stephens explains, existing tests that compare modeled versus observed cloud cover and/or top of the atmosphere (TOA) cloud radiative forcing are inadequate, because: “merely reproducing distributions of observed parameters independent of one another is not an adequate test of models since it is possible to tune to the observations using any one of many combinations of cloud parameters that, individually, might be unrealistic…Simple comparisons of model and observed cloud parameters does not provide any insight into the realism of those processes essential to feedback."... "In summarizing our present understanding of cloud feedbacks and, in particular, cloud feedbacks in the GCM climate models, Stephens offers the following remarks: “GCM climate and NWP models represent the most complete description of all the interactions between the processes that establish the main cloud feedbacks, [but] the weak link in the use of these models lies in the cloud parameterization embedded in them. Aspects of these parameterizations remain worrisome containing levels of empiricism and assumptions that are hard to evaluate with current global observations."… "Most analysis of feedback concentrates on the global-mean climate system and global-mean surface temperature defining cloud feedbacks as those processes that connect changes in cloud properties to changes in global-mean temperature. There is, however, no theoretical basis to define feedbacks this way nor any compelling empirical evidence to do so…." "Thus we are led to conclude that the diagnostic tools currently in use by the climate community to study feedback, at least as implemented, are problematic and immature and generally cannot be verified using observations.” "Notably, Stephens’s article explaining the seemingly important limitations on scientific knowledge about cloud feedback effects is never even cited in the IPCC’s 2007 AR4. This failure to mention and discuss such a widely cited article, and one that appeared some years before the 2007 AR, seems to indicate that the 2007 AR was not a full and complete assessment."
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Post by Pooh on Jul 24, 2010 6:02:21 GMT
Page 45, 46 d) Clouds and The Relationship between Weather and Climate
"A look at the literature thus reveals that the IPCC has just hinted at the scientific controversy over cloud feedback effects, and at just how much the climate predictions it advances rely upon what are basically just guesses about whether cloud feedback is likely to be positive or negative, and big or small. But clouds are actually even more central to the climate change debate than this."...
"Basically (and colloquially),the more efficient is the precipitation system’s response to rising atmospheric temperature (and hence water vapor), the more water vapor is recycled back to the surface as rainfall and the less water vapor remains in the atmosphere. Since water vapor is by far the most important greenhouse gas, the more efficient are precipitation systems at removing water vapor, the lower the equilibrium temperature increase from any radiative forcing (such as an increase in a different greenhouse gas, such as CO2).... Clouds with high precipitation efficiency produce cold and dry climates. This happens because most of the cloud condensed water falls out as rain, leaving little available to moisten the atmosphere.” The great defect in GCM climate studies can now be understood:
"Since climate equilibrium can be very sensitive to the cloud microphysical processes, any cumulus convection scheme adequate for use in GCM’s should be strongly based on them. Considering that the cumulus convection schemes currently in use in GCM’s are based on somewhat arbitrary moistening assumptions, they are probably inadequate for climate change studies.”
"In slightly less technical language, the huge problem with GCM climate models is that these models do not actually model the physical processes that produce precipitation systems, but instead set various parameters at values such that the models accurately reproduce spatial and temporal patterns in average precipitation. These models cannot shed any light at all on how the efficiency of precipitation systems might change due to a forced atmospheric warming."...
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