Human activity drastically altering rainfall patterns

Sunday, December 09, 2007 by: David Gutierrez, staff writer
Tags: rainfall, health news, Natural News

(NewsTarget) Global warming caused by industrial emissions has changed precipitation patterns worldwide, according to a new study published in the journal Nature. While many prior studies have demonstrated that emissions have led to rising global temperatures, this is the first major international study to examine the effects of human-related emissions on rainfall.

"It's the first time that we've detected in precipitation data a clear imprint of human influence on the climate system," said lead author Francis Zwiers.

Various climate models have been predicting global-warming related changes in rainfall patterns for years. Starting with 1925, Zwiers and colleagues examined global rainfall data, then compared it with 14 different computer climate models. They found that rainfall changes in the past 80 years do indeed fall in line with those predicted by the models.

Industrial emissions and global warming have caused the water cycle to become stronger, so that more water moves north, away from the warm equatorial region. This has resulted in increased rainfall in already wet areas and less in dry ones. In addition, the scientists say that higher fossil fuel use in the Northern Hemisphere is pushing the equatorial rain belt farther south, into the Southern Hemisphere.

The study concluded that climate change caused by industrial emissions is responsible for the majority of precipitation increases south of the equator and in the middle latitudes of the Northern Hemisphere. It has also resulted in less rainfall in the regions just north of the equator, including Mexico, Central America and northern Africa.

Zwiers said that the results of the study are particularly alarming, even in the realm of climate predictions.

"Temperature changes we can cope with," Zwiers said. "But water changes are much more difficult to cope with. That will have economic impacts and impacts on food production, and could ultimately displace populations."