The current uproar over the posture of the Bush Administration on global warming and, most recently, on power-plant emissions vividly illustrates the political hypocrisy and opportunism imbuing debates on environmental issues. Take first global warming. The charge that the current phase of global warming can be attributed to greenhouse gases generated by humans and their livestock is an article of faith among liberals as sturdy as is missile defense among the conservative crowd. The Democrats have seized on the issue of global warming as indicative of President Bush’s willful refusal to confront a global crisis that properly agitates all of America’s major allies. Almost daily, the major green groups reap rich political capital (and donations) on the issue.
Yet the so-called anthropogenic origin of global warming remains entirely nonproven. Back in the spring of this year, even the Intergovernmental Panel on Climate Change, which now has a huge stake in arguing the “caused by humans” thesis, admitted in its summary that there could be a one-in-three chance its multitude of experts are wrong. A subsequent report, issued under the auspices of the National Academy of Sciences, is ambivalent to the point of absurdity. An initial paragraph boldly asserting the caused-by-humans line is confounded a few pages later by far more cautious paragraphs admitting that the thesis is speculative and that major uncertainty rules on the role played in climate equations by water vapor and aerosols.
It’s nothing new to say the earth is getting warmer. I myself think it is, and has been for a long, long time. On my shelf is an excellent volume put out in 1941 by the Department of Agriculture called Climate and Man, which contains a chapter acknowledging “global warming” (that same phrase) and hailing it as a benign trend that will return the earth to the normalcy in climate it enjoyed several hundred thousand years ago.
Anything more than a glance at the computer models favored by the caused-by-humans crowd will show that the role of carbon dioxide is grotesquely exaggerated. Indeed, the models are incapable of handling the role of the prime greenhouse gas, water vapor (clouds, etc), which accounts for twenty-five to thirty times as much heat absorption as carbon dioxide.
Similarly, the Intergovernmental Panel on Climate Change admits to a “very low” level of scientific understanding on an “aerosol indirect effect” that the panel acknowledges is cooling the climate system at a hefty rate (aerosols are particles so fine they float in air).
In a particularly elegant paper published in May in Chemical Innovation, journal of the American Chemical Society, Professor Robert Essenhigh of Ohio State reminds us that for the past 850,000 years, global temperature and carbon dioxide have been moving up and down in lockstep. Since 849,700 of these years were ones preceding any possible human effect on carbon dioxide, this raises the question of whether global warming caused swings in carbon dioxide or vice versa. Essenhigh argues convincingly that the former is the case. As global temperatures warm, a huge reservoir of carbon dioxide absorbed in the oceans is released into the atmosphere. Clearly, this is a much more potent input than the relatively puny human contribution to global carbon dioxide. Thus natural warming is driving the raised level of carbon dioxide, and not the other way round.