El Nino occurs approximately every 5 years on average. It is also called El Nino Southern Oscillation Effect or ENSO. It occurs when the tropical Eastern Pacific Ocean has surface ocean temperatures that are warmer than usual. An increase of 0.5 degrees Celsius is the accepted definition for an El Nino and it can last between nine months to two years. It is coupled with high surface pressure in the Western Pacific. This leads to weather disturbances in areas all over the world. Droughts have been known to occur as well as flooding. This event is called El Nino because periodic warming usually occurs around Christmas time in South America and El Nino refers to the Christ child. The reasons behind El Nino are currently under scientific study.
El Nino is a natural phenomenon that refers to the Pacific Ocean warm currents near the coasts of Peru and Ecuador. The El Niño phenomenon dramatically affects the weather in many parts of the world. The strongest El Niño events of the 20th century occurred in 1982-'83 and in1997-'98. The effects of 1982-'83 included significant storms throughout the southwest United States and one of Australia's worst droughts of the century.According to the World Meteorological Organization, the 1997-'98 El Niño was a major factor in 1997s record high temperatures