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Use the pull down menu below to go to any of the El Niño/La Niña Watch pages.
A Mostly Quiet Pacific
November 03, 2003
Some climate forecast models indicate there is an above average chance that
there could be a weak to borderline El Niño by the end of November 2003.
However, the trade winds, blowing from east to west across the equatorial
Pacific Ocean, remain strong. Thus, there remains some uncertainty among
climate scientists as to whether the warm temperature anomaly will form
again this year. The latest remote sensing data from NASA's Jason satellite
show near normal conditions across the equatorial Pacific. There are currently
no visible signs in sea surface height of an impending El Niño.
This equatorial quiet contrasts with the Bering Sea, Gulf of Alaska and U.S.
West Coast where lower-than-normal sea surface levels and cool ocean
temperatures continue (indicated by blue and purple areas).
The image above is a global map of sea surface height, accurate to
within 30 millimeters. The image represents data collected and composited
over a 10-day period, ending on Nov. 3, 2003. The height of the water
relates to the temperature of the water. As the ocean warms, its level
rises; and as it cools, its level falls. Yellow and red areas indicate where the
waters are relatively warmer and have expanded above sea level, green
indicates near normal sea level, and blue and purple areas show where the
waters are relatively colder and the surface is lower than sea level. The
blue areas are between 5 and 13 centimeters (2 and 5 inches) below normal,
whereas the purple areas range from 14 to 18 centimeters (6 to 7 inches)
below normal.
The Jason satellite carries a dual-frequency radar altimeter. This instrument
beam microwave pulses-at 13.6 and 5.3 Gigahertz, respectively-downward
toward the Earth. To determine the ocean's height, the instrument precisely
measures the time it takes for the microwave pulses to bounce off the
surface and return to the spacecraft. This measure, multiplied by the speed
of light, gives the range from the satellite to the ocean surface. (For more
details, visit the Jason Website.)
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