Global warming may worsen droughts in U.S. Southwest, Middle East
Global warming may worsen droughts in U.S. Southwest, Middle East
mongabay.com
February 14, 2007
A new NASA study says that global warming could increase droughts in southwest United States, Mexico, parts of North Africa, the Middle East, and Australia — areas already stressed by periodic water shortages.
Comparing historical records of the climate impact of changes in the sun’s output with models projecting higher atmospheric concentrations of greenhouse gases, the researchers found “that a warmer future climate likely will produce droughts in the same areas as those observed in ancient times, but potentially with greater severity.”
“These findings strongly suggest that greenhouse gases and long-term changes in solar activity both can have major influences on climate via similar processes,” said Dr. Drew Shindell, lead author of the paper that appeared in the Dec. 27, 2006, issue of Geophysical Research Letters and a scientist at NASA’s Goddard Institute for Space Studies in New York. “There is some evidence that rainfall patterns already may be changing. Much of the Mediterranean area, North Africa and the Middle East rapidly are becoming drier. If the trend continues as expected, the consequences may be severe in only a couple of decades. These changes could pose significant water resource challenges to large segments of the population.”
Courtesy of NASA |
The model showed that while incidence of drought may increase in some parts of the world, precipitation may increase in other regions including western Pacific, equatorial areas, and in parts of southeast Asia.
“Precipitation is hard to predict because it is so highly variable, but these results increase our confidence that continued warming will be associated with large-scale changes in rainfall,” said Shindell.
The researchers say climate change in drought-susceptible areas likely affected past civilizations like the Pueblo people of American Southwest who left their cities in the 1300s.
This article is based on a news release from NASA.