- Slides: 11
El Nino! The Climate Event of the Century By: Katie Durham & Mike Magnuson
Que es el nino? • El Nino is a crucial climatic disturbance of the ocean and the atmosphere. • Characterized by a large scale deterrent of the trade winds and warming of the surface areas in the central and east equatorial Pacific. • Usually occurs at intervals of 27 years, averaging every 3 -4 years, lasting 12 -18 months at a time.
When did El Nino occur? • It has always been a natural, world-wide phenomenon. • Strongest El Nino intensity occurred from 1982 -83 and 199798. • Impacts seen most clearly in the winter.
Before and After • Made with a coupled oceanatmosphere model of the tropical Pacific • Data is collected using tide gauge stations
Delayed Oscillator Theory • Theory of origin • El Nino is due to rossby waves, which are reflected from the western boundary of the atmospheric system. • Causes kelvin waves to propagate eastward, driving the cold water that gives rise to El Nino.
E. N. S. O. • “El Nino Southern Oscillation” • Multi-annual shift in tropical sea level pressure between the eastern and western hemispheres. • Events monitored by satellites.
El Nino v. La Nina • Antipodes of one • • another. La Nina brings colder than normal sea surface temperatures in the equatorial Pacific. It also causes drier, warmer conditions to much of the southern U. S. during winter.
Impacts of El Nino in the U. S. • Winter temperatures in the continental U. S. tend to be warmer than normal in the N and W coast states and cooler than normal in the SE. • Conditions tend to be wetter than normal over central and southern California, the SW states and across much of the South. • Conditions are drier than normal over the N portions of the Rocky Mountains and in the Ohio valley.
Global effects of El Nino • El Nino brings wetter than normal conditions to Peru and Chile. • It brings dry conditions to Australia and Indonesia.
El Nino: 1997 -1998 • Lasted 14 months. • Largest and warmest El • • Nino to develop during the past 100 years. Received more attention at all levels than had any previous climate event. Scientists were able to use El Nino conditions to successfully predict climate conditions of the winter 6 months in advance.
Works Cited • Caviedes, Cesar N. El Nino in History: Storming • • • Through the Ages. Gainesville: University P of Florida, 2001. 46 -49. Changnon, Stanley A. , ed. El Nino: 1997 -1998. New York City: Oxford UP, 2000. 3 -4. D'Aleo, Joseph S. The Oryx Resource Guide to El Nino and La Nina. Westport, Conneticut: Oryx P, 2002. 9 -17. "El Nino and La Nina. " World Almanac and Book of Facts. 2004: 701 -702. Academic Search Premier. Dayton. 25 Mar. 2004