"Certain aspects of El Niño, such as equatorial Pacific sea-surface temperatures and related changes in precipitation patterns can now be predicted with confidence more than one year in advance,"

The new study used data from the ten-year Tropical Ocean Global Atmosphere (TOGA) project, an international research program that studied how Earth's oceans and atmosphere affect one another. The team's paper will be published today in the journal "Science." Busalacchi's co-authors are Dr. Dake Chen, University of Rhode Island, and Dr. Stephen Zebiak and Dr. Mark Cane of Columbia University's Lamont Doherty Earth Observatory, Palisades, NY.

TOGA has successfully completed its decadal mission and the world legacy of the Topical Atmosphere Ocean array and all the research infrastructure is in place. New programs will continue to move this research into operational application mode. In November, an "International Forum on Forecasting El Niño" will be held in Washington, DC. The forum will launch an International Research Institute for climate prediction.

The impact of El Niño on the continental United States is less direct than in the tropics, but still distinct. Increased precipitation over the Gulf Coast states and warmer winter temperatures over the north-central tier of Gulf Coast states are common, with important implications for the agricultural sector of the economy.

A common indicator of El Niño occurs when the warmest water of the global ocean shifts from the International Dateline in the Pacific eastward by 3,100 miles (5,000 kilometers), increasing sea-surface temperature by 4 to 7 degrees Fahrenheit (2 to 4 degrees Centigrade). This eastward migration of a heat source critical to the atmosphere changes global weather patterns, including precipitation and temperature, far beyond the equatorial Pacific.

"That's the breakthrough," said Busalacchi. "This is the first time data are being assimilated into a coupled model, and that's what gives us this expanded forecasting capability."

"Developing and developed countries are getting this data through one-on-one contacts and through NOAA. They're beginning to use these forecasts to adapt to these events and to mitigate their dangers. Advances such as these suggest that it is time to implement a process to issue El Niño forecasts on a routine basis, so that the affected countries may benefit from this information," Busalacchi said.

This kind of computer model, and its use to predict changes in the Earth's environment, is the heart of NASA's Mission to Planet Earth and the U.S. Global Change Research Program. A long-term, coordinated research program, Mission to Planet Earth is designed to provide near-term benefits. The program provides improved forecasting of economically threatening climate changes such as El Niño, with improved understanding of the Earth's climate and how it changes.

Mission to Planet Earth combines surface measurements and computer models with space-based measurements to provide a view of the Earth's global environment. Busalacchi's model, for example, will increase in importance when the NASA Scatterometer begins returning worldwide data on sea-surface winds. The instrument is scheduled for launch in August 1996 aboard a Japanese satellite.