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El Niņo El Niņo a warm current of water El Niņo (Spanish name for the male child), initially referred to a weak, warm current appearing annually around Christmas time along the coast of Ecuador and Peru and lasting only a few weeks to a month or more. Every three to seven years, an El Niņo event may last for many months, having significant economic and atmospheric consequences worldwide. During the past forty years, ten of these major El Niņo events have been recorded, the worst of which occurred in 1997-1998. Previous to this, the El Niņo event in 1982-1983 was the strongest. Some of the El Niņo events have persisted more than one year. In the tropical Pacific, trade winds generally drive the surface waters westward. The surface water becomes progressively warmer going westward because of its longer exposure to solar heating. El Niņo is observed when the easterly trade winds weaken, allowing warmer waters of the western Pacific to migrate eastward and eventually reach the South American Coast . The cool nutrient-rich sea water normally found along the coast of Peru is replaced by warmer water depleted of nutrients, resulting in a dramatic reduction in marine fish and plant life. Animation by: Shao In contrast to El Niņo, La Niņa (female child) refers to an anomaly of unusually cold sea surface temperatures found in the eastern tropical Pacific. La Niņa occurs roughly half as often as El Niņo. |