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Can malaria be predicted by changes in ocean temperatures? Can you foretell a dengue fever epidemic by reading atmospheric pressures? Does hantavirus disease follow El Niño? Are climatologists the doctors of the future?

The answer is yes. At least climatologist Nicholas Graham at Scripps Institution of Oceanography in La Jolla thinks so. If you can predict El Niño, Graham believes, you can predict where and when malaria will strike, where droughts will hit, where cholera can float to. You can save lives.

Since this latest El Niño began, Graham has become the world's tour guide to climate change. He's taken the phrase "applied science" to a new level. Will cows on the Serengeti plains have grass to eat in 1999? Ask Nick. Will the tsetse fly spread south of the Tropic of Cancer this year? Ask Nick. Ask him if cholera will become epidemic in Bangladesh in the next monsoon. If there will even be a monsoon next season.

Lots of world leaders ask Nick. The Scripps climatologist regularly consults with heads of state. Last week he was prophesying in Brazil, where half the country has been inundated with rains and the other half has endured drought conditions. This week, for the fourth time in a year, he's in East Africa, which is also suffering from El Niño-driven flooding.

El Niño, Graham says, is key to just about everything. It's because of El Niño that he has this job, that the National Oceanic and Atmospheric Administration (NOAA) decided to team up with Columbia University's Lamont-Doherty Earth Observatory and Scripps Institution of Oceanography to form the International Research Institute for Climate Prediction.

"We were all jerked into action by the 1982-1983 El Niño," says Graham. "It had devastating consequences around the world. There was a big effort to understand El Niño -- the warming of the tropical Pacific -- and its impact on the climate elsewhere. And to try to predict it next time."

They predicted this one fine.

The El Niño effect refers to a pool of warm water, twice as large as the U.S., that usually surrounds Indonesia on the far-western rim of the Pacific. It is normally kept in place there by the pressure of tradewinds blowing westward from the Americas. When those tradewinds fail, the whole pool drifts eastward, not stopping till it collides with Peru. But its influence is felt as far away as Africa. El Niño has been called the most influential worldwide natural event after the four seasons. It profoundly influences just about everything, from droughts in Australia to hantavirus dangers in California.

When he's not on the road, Nick Graham watches it all from his desktop screen in La Jolla, checking six or seven computer "models" -- projections of climate predictions -- from around the academic world. He clicks on his keyboard and great flumes of red gush out across his computer screen. They are satellite views of El Niño straddling the Pacific, like a rocket exhaust tail spewing out of Peru. Each of the models uses data from satellites, water-temperature statistics, and other input to predict what's going to happen next.

The stated goal of the research institute, Graham says, is to make "the best possible climate predictions and distribute the information in useful format especially rapidly for interested parties such as public health authorities and fishery people."

"This is the big test year," says Simon Mason, one of Graham's two assistants. Mason says El Niño is the perfect "test bed" because it covers a specific area of natural "global warming"-- the Pacific. El Niño acts as a model to work out the kinks in the quest to predict all weather and global warming on a worldwide basis.

Graham and his colleagues have teamed up with public- health experts to predict disease epidemics that El Niño may encourage. Warmer temperatures and increased rainfall to our region, he says, spread water and insect-borne diseases such as malaria, its cousin dengue fever, cholera, and hantavirus. Some researchers even believe that a current outbreak of cholera as far away as the horn of Africa is linked to El Niño.

Graham has been studying the spread of malaria -- which afflicts more than 300 million people a year around the world -- in Colombia. "There," he says, "you can see a very clear relationship between El Niño occurrences and malaria outbreaks. When there's an El Niño, there tends to be a lot of malaria. Also dengue fever."

He and a Colombian scientist have been studying cases of malaria reported there since 1960. The years with the most cases almost all coincide with the presence of El Niño. Ironically, Colombia, though warmer, is drier during an El Niño. "That means more stagnant puddles for mosquitoes to breed in," explains Graham. Graham reported to the American Geophysical Union in December that his models predicted increased temperatures for Colombia in 1998. More modeling showed that as the weather warms, mosquitoes and other insects will increase their range into higher elevations that were previously malaria-free. "It is temperature occurrences associated with El Niño that affect their life cycle," says Graham, "how often they eat, how fast the protozoa that spreads malaria takes to develop inside the mosquito depend on temperature fluctuations and contribute to the increase in malaria cases there."

At least, he notes, he has been able to warn the Colombians in time to stock up on appropriate medicines.

But not all countries react the same to El Niño: another study published in December suggests that in Venezuela, it is the year after an El Niño that the number of malaria cases shoots up by a third.

Graham believes the main element governing these outbreaks is the ocean temperatures. The warm waters are here off the Americas, but their effects can be far-ranging. "In Central East Africa, where they had tremendous flooding this year," says Graham, "they've got huge disease problems now. The flooding was induced by El Niño. Now [with unseasonal rains] in normally dry areas they have lots and lots of standing water. Then you get not just the vector-borne diseases [like malaria] but the ones spawned in overwhelmed sewage systems [that] flood into the public water supply."

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