TBO.com - TBO is Tampa Bay Online

Earth's Tropical Zone Is Expanding

ADVERTISEMENT

By SETH BORENSTEIN, The Associated Press

Published: December 3, 2007

WASHINGTON - Earth's tropical belt seems to have expanded a couple hundred miles over the past quarter century, which could mean more arid weather for some already dry subtropical regions, new climate research shows.

Geographically, the tropical region is a wide swath around Earth's middle stretching from the Tropic of Cancer, just south of Miami, to the Tropic of Capricorn, which cuts Australia almost in half. It's about one-quarter of the globe and generally thought of as hot, steamy and damp, but it also has areas of brutal desert.

To meteorologists, however, the tropics region is defined by long-term climate and what's happening in the atmosphere. Recent studies show changes that indicate an expansion of the tropical atmosphere.

The newest study, published Sunday in the new scientific journal Nature Geoscience, shows that by using the weather definition, the tropics are expanding toward Earth's poles more than predicted. Climate scientists long have predicted a growing tropical belt toward the end of the 21st century because of manmade global warming.

What has happened in the past quarter century, however, is larger and more puzzling than initially predicted, said Dian Seidel, a research meteorologist with the National Oceanic and Atmospheric Administration lab in Silver Spring, Md. She is the author of the newest study.

Seidel said she has not determined the cause of this tropical belt widening.

Share this:

Loading Comments...

Email Print

ADVERTISEMENT