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El Niño Bears Unwanted Gifts
El Niño is a weak warm current of water that appears for several weeks each Christmas off the coast of Ecuador and Peru. Every three to five years, however, this otherwise mild-mannered current becomes a real "hazard spawner," says NCAR senior scientist Michael Glantz, by growing in size and strength and lasting for many months. Unusual weather conditions result as tropical monsoons that normally center over Indonesia shift eastward, influencing atmospheric wind patterns around the world. Massive fish kills, droughts, heavy rains, hurricanes: These are just some of the gifts that a robust El Niño can bear.
After a particularly devastating El Niño event in 1982-1983, researchers vowed not to be caught off guard again. NSF coordinated a global scientific effort to set up a network of ocean-drifting, data-gathering buoys in the Pacific Ocean. In the spring of 1997, the investment paid off when the instruments began recording abnormally high temperatures off the coast of Peru, giving scientists and policymakers their first inkling of an El Niño event that would turn out to be the most devastating in fifty years. Supplemented with satellite observations, the advance warning from the buoys allowed farmers in Central and South America to steel themselves for record-breaking drought and Californians to fix their roofs before the onset of an unprecedented rainy season that also caused life-threatening floods and mudslides. Now NCAR researchers are incorporating what they've learned about this massive El Niño event into supercomputer-based climate models designed to simulate atmospheric circulation changes over the course of decades and even centuries. And in May 1999, NCAR began working with the United Nations Environment Programme to conduct a nineteen-month study of the impact of the 1997-98 El Niño, with the goal of developing programs to help countries better prepare themselves for the day when El Niño makes a muscular come-back.
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