Climate Change - El Nino

El Niño is an oscillation of the ocean-atmosphere system in the tropical Pacific, and has important consequences for weather around the world.

El Niño happens every three to seven years.

“El Niño” is Spanish for “The Christ Child”.

Peruvian fishermen named the event many years ago.
They noticed that every few years around Christmas, virtually no fish could be found in the unusually warm waters. 
El Niño is marked by unusually warm ocean temperatures in the Equatorial Pacific.

The opposite conditions are called La Nina, characterized by unusually cold ocean temperatures in the Equatorial Pacific. 

El Nino clearly affects global temperatures.

One piece of evidence that world temperatures are rising is that every La Nina ‘year’ since 1998 was warmer than every El Nino ‘year’ before 1995:  


As the Earth warms, each El Nino 'rides' on a higher base-line global temperature:

Information about El Nino is provided in bulletins produced by the US National Weather Service and the Australian Bureau of Meteorology.

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