Friday, May 1, 2009

Part 2 of Debunking the Silliness of Global Warming Skeptics


"What do the global warming crowd believe?"

The primary thrust of the page is that the climate can't be studied scientifically because it is too complex and can't be subject to experiments and that computer models can't be a substitute for experimentation. This is a very naive perspective. Complex and chaotic systems are studied all the time with rigorous scientific methodologies that recognize the difficulties in experimentation and adjust for them by examining a system's determinism and sensitivity to both initial conditions and changing inputs. There is a very good discussion of this at the New England Complex Systems Institute that talks about the science of complex systems. And the idea that models aren't part of the scientific process is ignorant - science is all about using theories and models to explain observed behavior.

The way to validate the accuracy of a model of a complex system is to examine the degree to which it can predict past and present observations. In this regard, the models used for AGW have actually been extremely good even before they were enhanced through computerization. Starting with Jim Hansen's predictions back in 1988 (see page 7 of his 1988 publication) which map very well to actual temperatures (see this graphic, the "scenario B" line, which was between optimistic and pessimistic scenarios and maps quite well with observed surface and ocean temperatures). And the IPCC reports in 2001 included model-to-actual comparisons that looked at natural causes only, man-made (anthropogenic) causes only and combined causes. The combined models matched observed temperatures very accurately.

The Transtronics article also seems to imply that the scientists working on climatology don't know what the scientific method is or what is the difference between a fact and a theory which is just ludicrous given the pedigree of the scientists that have contributed to the current body of knowledge. It helps to know that the first advancement of the theory of AGW was not Al Gore or the International Panel on Climate Change (IPCC), but was back in 1896 by Svante Arrhenius and although it wasn't so much a model, his formulas proved to be remarkably accurate in predicting current warming trends (although he over estimated the greenhouse effect of CO2 and underestimated the amount that would be emitted). In fact, there is a very good discussion of the history of climate science that shows how the science and theory has advanced over time, using the basic tenants of the scientific method all along. In short, this article takes a remarkably naive approach to climate science and one that is not based on any facts that I can find.

I can't let pass the fact that the first part of this article is the graph derived directly from the data the NSSTC. It's not clear what is supposed to be proven with this graph, but the text around it states "it is my take that the the claim of significant man caused global warming can only be called speculation at this point in time (2007)". It is my guess that the author (I'll just assume it's a "he") is trying to show a lack of warming in the raw satellite data, a situation that has had significant attention from real climate scientists. Turns out the satellite temperature data is complex and much of the previous conclusions from the data were false due to errors in the interpretation. Those errors have been scientifically identified and corrected and guess what - the more accurate interpretations match the climate model predictions quite well. And regardless, the atmospheric temperature record is just one component - surface and ocean temperatures are also rising at approximately the rate predicted by the climate models.

More to come later...

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