The Miami Herald
December 18, 1998

             El Niño defeats rain forest benefit

             Associated Press

             In an El Niño year, Brazil's rain forest exhales millions of tons of heat-trapping
             carbon dioxide, potentially adding to global warming, scientists say.

             Under normal conditions the rain forest acts as the ``lungs'' of the planet. Its dense
             canopy of trees stretches for thousands of miles, releasing oxygen and absorbing
             as much as 700 million tons of carbon dioxide a year.

             But when global climate conditions are scrambled by El Niño and the rain forest
             becomes parched, the Amazon Basin produces as much as 200 million tons of
             excess carbon dioxide a year, scientists from the Woods Hole Research
             Laboratory in Massachusetts determined. The calculations were published in
             Thursday's journal Nature.

             The study examined three El Niño episodes from 1980 to 1994. It did not include
             measurements of the record-setting El Niño in 1997-98, but the trend is clear,
             researchers said.

             ``In El Niño years, which bring hot and dry weather to much of the Amazon, the
             ecosystems act as a source of carbon,'' said researcher Hanqin Tian.

             Scientists say understanding the planet's fluctuating carbon cycle is a key step in
             accurately predicting -- and managing -- global warming in the 21st Century.

             Many natural features on the planet act as ``carbon sinks'' to absorb excess
             carbon and help to stabilize the planet's climate. The oceans and the rain forests
             absorb the largest shares, along with tundra and rangeland.

             But not always.

             During an El Niño, a vast pool of warm water expands in the equatorial Pacific. It
             upsets weather patterns around the world. In the Amazon, it triggers severe

             Under such severe stress, the forest can't adequately photosynthesize and store
             carbon dioxide, Tian said.