April 21, 2006

Media, academic journals in cahoots on global warming

According to Brian Montopoli writing for the CBSNews.com blog, 60 Minutes correspondent Scott Pelley said, “There is virtually no disagreement in the scientific community any longer about global warming. The science that has been done in the last three to five years has been conclusive…. What you do see in the data again and again and again is this almost lockstep increase between the levels of CO2 and the rise of temperature in the atmosphere. And the climate models that predicted these things happening 15 years ago have proven to be accurate…. It would be difficult to find a scientist worth his salt in this subject who would suggest this wasn’t happening.”

As to Pelley’s first point, that levels of carbon dioxide have risen in “lockstep” with temperatures: street-side lemonade sales rise in “lockstep” with increasing temperatures, and street-side hot-chocolate sales rise in “lockstep” with falling temperatures. However, it would be ridiculous to suggest that lemonade is causing higher temperatures or that hot chocolate is causing lower temperatures. Correlation does not imply causation.

Second, contrary to what CBS would have you believe, climatologists are not in agreement over the catastrophic consequences of a slight global temperature increase. According to Richard Lindzen, an Alfred P. Sloan Professor of Atmospheric Science at MIT, “If the models are correct, global warming reduces the temperature differences between the poles and the equator. When you have less difference in temperature, you have less excitation of extratropical storms, not more. And, in fact, model runs support this conclusion.

Alarmists have drawn some support for increased claims of tropical storminess from a casual claim by Sir John Houghton of the United Nations’s Intergovernmental Panel on Climate Change (IPCC) that a warmer world would have more evaporation, with latent heat providing more energy for disturbances. The problem with this is that the ability of evaporation to drive tropical storms relies not only on temperature but on humidity as well, and calls for drier, less humid air. Claims for starkly higher temperatures are based upon the presence of humidity, not less—hardly a case for more storminess with global warming.”

Lindzen and colleagues claim that clouds mitigate the effect of rising surface temperatures through a negative-feedback mechanism they dubbed the “Iris Effect.” A 2001 paper by Lindzen, Ming-Dah Chou, and Arthur Hou, argues that a rise in mean sea surface temperature (SST) will cause high-altitude clouds to contract, decreasing their area. In turn, that will mitigate the effect of rising surface temperatures.

According to Lindzen’s theory, the high clouds act analogously to an eye’s iris: When the surface temperature is high, the clouds contract to allow heat to escape, just as the pupil contracts when it is light and expands when it is dark. Lindzen finds that “the area of high cloud per unit area of cumulus decreases by about 22 percent per degree Celsius increase in cloud-weighted SST. Reflecting the reduced scatter, the standard error for the slope is about 8 percent. Again using three times the standard deviation as our uncertainty, the decrease for an increase of 1 Kelvin in cloud-weighted SST lies between 17 percent and 27 percent.”

Lindzen argues that climatologists have been “cowed” into silence by a scientific establishment wholly uninterested in scientific truth. According to Lindzen’s editorial, the IPCC defended many of its radical policy suggestions with the work of paleoclimatologist Michael Mann. Mann claimed that the ’90s were the warmest decade—and 1998 the warmest year—in the past thousand years. When Texas Representative Joe Barton sought the details of Mann’s research, Mann refused to release the details, making it nearly impossible for others to attempt to replicate his results. Lindzen writes, “The scientific community’s defense of Mr. Mann was, nonetheless, immediate and harsh.” Apparently, an elected official’s request for the details of taxpayer-funded analysis constituted “intimidation,” and the American Meteorological Society, American Geophysical Union, and National Academy of Sciences decided to circle the wagons around poor Mann.

Science is not advanced through consensus. The truth is determined through research, not majority vote (though CBS frequently finds facts inconvenient). Unless scientific societies, peer-reviewed journals, and, indeed, the scientists themselves are receptive to alternative models and minority theories, the academic environment will remain hostile to science.

The discussion on global warming is far from finished, but that’s certainly not the impression you get from watching CBS.