Transition from El Nino to La Nina Affected Vegetation

NASA scientists using satellite data have shown that shifts in rainfall patterns from one of the strongest El Niño events of the century in 1997 to a La Niña event in 2000 significantly changed vegetation patterns over Africa.

Assaf Anyamba and Compton Tucker of Goddard and Robert Mahoney of Global Science and Technology Inc (GST) analyzed satellite derived images of vegetation from 1997 to 2000. They noticed regions of above normal "greenness" over East Africa associated with patterns of above normal rainfall during the 1997-1998 El Niño event. At the same time, they observed below normal "greenness" over southern Africa associated below normal rainfall conditions there.

During the transition to La Niña, rainfall patterns reversed. Southern Africa experienced above normal rainfall and East Africa received below normal rainfall, resulting in a corresponding reversal of vegetation greenness patterns.

For the complete article on the affects of La Nina, go to: http://www.gsfc.nasa.gov/topstory/20021101elnino.html