|Vol. 24, No. 14||Feb. 10, 1999|
BY BOB NELSON
The recurrent warming of the eastern equatorial Pacific Ocean known as El Niņo set record highs last year. Sea surface temperatures rose 11 degrees Fahrenheit and chaotic weather plagued the Pacific rim and elsewhere.
But scientists missed the event. Computer models developed in several laboratories around the world, including that of Mark A. Cane and Stephen E. Zebiak at Columbia's Lamont-Doherty Earth Observatory, failed to predict the severity of the 1997-98 El Niņo, demonstrating the limits of physical models.
Now Cane, a Columbia climate scientist who with Zebiak was the first to develop computer models designed to predict El Niņo, will examine last year's severe event and use it to illustrate the perils and potential of climate forecasting.
He will deliver the 77th University Lecture on Monday, Feb. 15 at 8 p.m. in Low Rotunda. There is no admission fee and the public is invited to attend.
Cane, the G. Unger Vetlesen Professor of Earth and Climate Sciences, became intrigued by El Niņo after the severe winter of 1977 in the Northeast was blamed on the recurring phenomenon. The event of 1982-83, which caused $13 billion worldwide in weather-related crop damage, flooding, injury and death, not only was not predicted, but was not recognized as a single phenomenon even when well under way.
Working at Lamont, Columbia's earth sciences campus in Palisades, N.Y., Cane and his colleague Zebiak, senior research scientist, by 1986 had developed the first computer model that successfully predicted the El Niņos of the late 1980s. The model is based on physical laws that simulate the complex interactions between ocean and atmosphere in the tropical Pacific, where the eastward migration of a large pool of warm water has worldwide climatic effects.
In much of the tropics the consequences of El Niņo are virtually certain, but in subtropical latitudes such as those occupied by the United States, says Cane, El Niņo must be viewed as creating a bias to prefer certain climatic patterns, rather than a sure thing.
In 1994, Cane and colleagues showed that information about El Niņo could be used to predict corn harvests a year in advance and halfway around the globe in southern Africa, where the region's worst drought in a century affected nearly 100 million people in 1991-92. Expensive, large-scale relief efforts by local governments and the international community, including some $800 million by the United States, were needed to avert widespread famine. The drought could have been predicted with a high degree of confidence using computer models, Cane said.
To make use of the predictive capacities developed at Columbia and at the Scripps Institution of Oceanography at the University of California, San Diego, in 1997 a new International Research Institute for Climate Prediction (IRI) was formed as a partnership among Columbia, Scripps and the National Oceanographic and Atmospheric Administration.
The IRI now distributes climate forecasts several months to a year in advance to decision- makers around the globe. Scientists work actively with farmers, fisherman, relief workers, transportation experts, water resource and utilities managers and others to find the best way to use this forecast information to avoid or reduce the human and economic devastation caused by extreme weather.