El Nino BIG IDEA: Abiotic and biotic factors influence the environment

Large-scale changes in atmospheric and ocean current patterns in which, among other things, warms surface water in the Pacific moves further to the east than normal

NORMAL: A convection cell is driven by heat at the ocean surface Water from the surface evaporates and the warm, moist water rises, pulling in cool, dry air,and creating a loop that transfers heat and moisture out of the hot zone.

El Niño: During an El Niño, the hot spot moves east,creating two convection cells and altering climate around the Pacific basin.

The red indicates sea-surface temperature 5 degrees C above

A warmer ocean translates into more humidity and clouds in the area, thus creating global changes in jet stream circulation.

Since it's heat that drives the weather -- differences in temperature and pressure literally move air and moisture around the sky -- if you change the source of heat, you change the entire weather system.

Effects of El Nino More hurricanes in the Pacific Induced droughts in the Amazon and Indonesia leading to fires Intense rains in areas that are characteristically dry Major storms in the NE U.S. Flooding in the SE U.S.

catches of tropical fish off the West Coast of the United States Global economy losses of around 8 billion dollars

La Nina Large-scale changes in atmospheric and ocean current patterns in which, among other things, warms surface water in the Pacific moves further to the west than normal

This results in below-normal sea surface temperatures in the eastern equatorial Pacific Effects tend to be the opposite of El Nino such as below normal precipitation in areas of the U.S.

Why do El Nino and La Nina Occur? El Niño and La Niña result from interaction between the surface of the ocean and the atmosphere in the tropical Pacific. Changes in the ocean impact the atmosphere and climate patterns around the globe.

In turn, changes in the atmosphere impact the ocean temperatures and currents. The system oscillates between warm (El Niño) to neutral (or cold La Niña) conditions with an on average every 3-4 years.