deserts on the move!

Over the past 25 years the tropics have expanded by as much as 300 miles (500 kilometers) north and south—evidence of climate change in action, a new study says.

This not only means that rain-drenched regions near the Equator are growing, experts say, but also that global warming may be pushing deserts poleward in places such as the U.S. Southwest, Mexico, Australia, South Africa, South America, and the Mediterranean.

“The rate of increase is pretty big,” said study lead author Dian Seidel of the National Oceanographic and Atmospheric Administration’s (NOAA) Air Resources Laboratory in Silver Spring, Maryland. “It’s several degrees of latitude over the course of 25 years.”

National Geographic, 3 Dec 2007