El Nino: it's back! (Climate).
When sea-surface temperatures across the equatorial Pacific Ocean measure 0.5[degrees]C above average for any particular 3-month period--as they did this year for April, May, and June--it heralds the onset of the worldwide weather maker known as El Nino.
Early this year, an increase in ocean temperatures in the central Pacific led researchers at the National Oceanic and Atmospheric Administration Noun 1. National Oceanic and Atmospheric Administration - an agency in the Department of Commerce that maps the oceans and conserves their living resources; predicts changes to the earth's environment; provides weather reports and forecasts floods and hurricanes and (NOAA NOAA
National Oceanic and Atmospheric Administration
Noun 1. NOAA - an agency in the Department of Commerce that maps the oceans and conserves their living resources; predicts changes to the earth's environment; ) to suggest that an El Nino was on the way. Around the same time, NASA NASA: see National Aeronautics and Space Administration.
in full National Aeronautics and Space Administration
Independent U.S. scientists analyzed patterns of wind and rainfall southeast of India and predicted an El Nino would appear between July and October (SN: 3/2/02, p. 142). From temperature data collected by satellites, buoys, and ships, NOAA made it official on July 11: The agency announced that the latest El Nino had indeed arrived.
The last El Nino, the strongest on record, began in 1997. It lasted about 13 months and, for that period, boosted average global land temperatures by more than 0.8[degrees]C. Although NOAA scientists aren't yet sure, they suspect that this year's El Nino will be weaker than 1997's says Jim Laver, director of the agency's Climate Prediction Climate prediction refers to :
In any case, effects of the new El Nino probably won't shown up in the United States United States, officially United States of America, republic (2005 est. pop. 295,734,000), 3,539,227 sq mi (9,166,598 sq km), North America. The United States is the world's third largest country in population and the fourth largest country in area. until fall. Typical El Nino winters bring warmer-than-normal temperatures to a region stretching from southern Alaska to the upper Midwest The Upper Midwest is a region of the United States with no universally agreed-upon boundary, but it almost always lies within the US Census Bureau's definition of the Midwest and includes the states of Minnesota and Wisconsin, as well as at least the Upper Peninsula of Michigan. and enhance rainfall across the country's southern tier. Other effects include increased rainfall in Peru and drought in Indonesia and other areas of the western Pacific.--S.P.