Global warming delusions..

An excellent article in the Wall Street Journal by Daniel Botkin, president of the Centre for the Study of the Environment and Professor Emeritus in the Department of Ecology, Evolution, and Marine Biology at the University of California.

Global warming doesn't matter except to the extent that it will affect life -- ours and that of all living things on Earth. And contrary to the latest news, the evidence that global warming will have serious effects on life is thin. Most evidence suggests the contrary.

Case in point: This year's United Nations report on climate change and other documents say that 20%-30% of plant and animal species will be threatened with extinction in this century due to global warming -- a truly terrifying thought. Yet, during the past 2.5 million years, a period that scientists now know experienced climatic changes as rapid and as warm as modern climatological models suggest will happen to us, almost none of the millions of species on Earth went extinct. The exceptions were about 20 species of large mammals (the famous megafauna of the last ice age -- saber-tooth tigers, hairy mammoths and the like), which went extinct about 10,000 to 5,000 years ago at the end of the last ice age, and many dominant trees and shrubs of northwestern Europe. But elsewhere, including North America, few plant species went extinct, and few mammals.

We're also warned that tropical diseases are going to spread, and that we can expect malaria and encephalitis epidemics. But scientific papers by Prof. Sarah Randolph of Oxford University show that temperature changes do not correlate well with changes in the distribution or frequency of these diseases; warming has not broadened their distribution and is highly unlikely to do so in the future, global warming or not.

The key point here is that living things respond to many factors in addition to temperature and rainfall. In most cases, however, climate-modeling-based forecasts look primarily at temperature alone, or temperature and precipitation only. You might ask, "Isn't this enough to forecast changes in the distribution of species?" Ask a mockingbird. The New York Times recently published an answer to a query about why mockingbirds were becoming common in Manhattan. The expert answer was: food -- an exotic plant species that mockingbirds like to eat had spread to New York City. It was this, not temperature or rainfall, the expert said, that caused the change in mockingbird geography.