Scientists studying variations in tropical heat and rainfall since the mid-1980s have found a strong link between warm periods and more extreme downpours.

The observed rise in the heaviest rains is about twice that produced by computer simulations used to assess human-caused global warming, said the researchers.

Other studies have already measured a rise in heavy rains in areas as varied as North America and India, and climatologists have long forecast more heavy rains in a world warmed by accumulating greenhouse gases.

Scientists studying variations in tropical heat and rainfall since the mid-1980s have found a strong link between warm periods and a rise in the frequency of the most extreme downpours.
The observed rise in the heaviest tropical rains is about twice that produced by computer simulations used to assess how human-caused global warming could change rainfall, said the researchers.

The National Center for Atmospheric Research, an important hub for work on the causes and consequences of climate change, has shut down a program focused on strengthening poor countries' ability to forecast and withstand droughts, floods and other climate-related hazards.

The move, which center officials say resulted from the shrinking of federal science budgets, is being denounced by many experts on environmental risk, who say such research is more crucial than ever in a world with rising populations exposed to climate threats.

By John P. Holdren Published: August 4, 2008

The few climate-change "skeptics" with any sort of scientific credentials continue to receive attention in the media out of all proportion to their numbers, their qualifications, or the merit of their arguments. And this muddying of the waters of public discourse is being magnified by the parroting of these arguments by a larger population of amateur skeptics with no scientific credentials at all.