El Nino

About every three to five years a large area of warmer water appears and persists for over a year. Rain fall patterns which lead to floods and droughts in tropical and semitropical areas, are strongly influenced by the surface temperature of ocean around the world particularly the pattern of ocean surface temperature in the Pacific off the coast of South America.

The warm shallow water of the ocean prevents nutrients needed by fish from reaching the surface from lower colder levels. The resulting decline in the fish population has a devastating effect on the fish industry.