The tropical Pacific Ocean has transitioned from last winter's
El Niño conditions to a cool La Niña, as shown by new data about
sea surface heights, collected by the U.S-French Ocean Surface
Topography Mission (OSTM)/Jason-2 oceanography satellite. This
OSTM/Jason-2 image of the Pacific Ocean is based on the average
of 10 days of data centered on Sept. 3, 2010. A new image
depicts places where the Pacific sea surface height is higher
(warmer) than normal as yellow and red, with places where the
sea surface is lower (cooler) than normal as blue and purple.
Green indicates near-normal conditions. Sea surface height is an
indicator of how much of the sun's heat is stored in the upper
ocean. La Niña ocean conditions often follow an El Niño episode
and are essentially the opposite of El Niño conditions. During a
La Niña episode, trade winds are stronger than normal, and the
cold water that normally exists along the coast of South America
extends to the central equatorial Pacific. La Niña episodes
change global wea