A climatic event occurring every two to seven years, characterized by warming of surface waters and reduced upwelling of cold, nutrient-rich water off the western coast of South America, causing die-offs of plankton and fish and influencing jet stream winds, altering storm tracks and affecting the climate over much of the world.
A warming of the surface water of the eastern and central Pacific Ocean, occurring every 4 to 12 years and causing unusual global weather patterns. An El Niño is said to occur when the trade winds that usually push warm surface water westward weaken, allowing the warm water to pool as far eastward as the western coast of South America. When this happens, the typical pattern of coastal upwelling that carries nutrients from the cold depths to the ocean surface is disrupted, and fish and plankton die off in large numbers. El Niño warming is associated with the atmospheric phenomenon known as the southern oscillation , and their combined effect brings heavy rain to western South American and drought to eastern Australia and Indonesia. El Niño also affects the weather in the United States, but not as predictably.
A variant, less correct, spelling of El NiÃ±o.
(place, proper) A warm inshore current annually flowing south along the coast of Ecuador and, about every seven to ten years, extending down the coast of Peru, where it has a devastating effect (El Niño Effect) on weather, crops, fish, etc.
Origin of el-nino
- American Spanish (originally used by fisherman in Ecuador and Peru as a name for the warm ocean current typically appearing around Christmastime in El Niño years) from Spanish the Christ child el the (from Latin ille al-1 in Indo-European roots) niño child (from Old Spanish ninno) (from Vulgar Latin nīnnus)
From American Heritage Dictionary of the English Language, 5th Edition