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Recent (early June, 1999) record high temperatures along the United State’s east coast are being linked to La Niña by scientists at the National Center for Atmospheric Research and NOAA’s Climate Prediction Center. During La Niña unusually cold water pools along the tropical Pacific Ocean. This sea surface temperature anomaly causes strange summer weather around the world, such as drought in the Mid-Atlantic states, cool temperatures in California, and rain in Indonesia.
The above image shows the La Niña as seen by TOPEX-Poseidon and NOAA's polar orbiting environmental satellites. Above average sea surface heights are raised, while those lower than normal are lowered. Warm water is orange
and red and cooler than normal water is blue. When the data for this image was collected, in February of 1999, La Niña was expected to diminish, but it is currently predicted to increase in strength through the end of the
La Niña is an occurrence of unusually cold water temperatures in the Pacific Ocean along the equator (the precise area affected is outlined in black in the image above). La Niña and its opposite, El Niño, are linked to seesaw variations in air pressure over the tropical Pacific and affect weather patterns across the globe. NASA monitors developing El Ni&ntidle;o and La Niña events by observing sea surface temperatures. This image compares the water temperatures observed in late January 2006 to long-term average conditions for that time of year. The recent data were collected by the Advanced Microwave Scanning Radiometer for EOS (AMSR-E). Red shows where sea surface temperatures are warmer than normal and blue where they are colder than normal.