La Niña

According to the National Oceanic and Atmospheric Administration, studies have shown that the temperature from La Niña has decreased since December 1997

December 1997 December 2000

Sea temperature anomalies in Celsius
http://www.elnino.noaa.gov/lanina.html

The La Nina is the opposite of El Nino. El Nino is to lower the surface temperature of a the sea, compares to La Nina which is suppose to raise the temperature of the sea's water. But lately when La Nina appears, the temperature has been declining.

http://en.wikipedia.org/wiki/La_Ni%C3%B1a