Use the pull down menu below to go to any of the El Niño/La Niña Watch pages.
Warm Pacific Water Wave Heads East, But No El Niño Yet
July 27, 2004
Recent sea-level height data from the U.S./France Jason altimetric satellite during a 10-day
cycle ending July 27, 2004, show that weaker than normal trade winds in the western and
central equatorial Pacific during June have triggered an eastward moving, warm Kelvin wave.
In the central equatorial Pacific, this "warm wave" appears as the large area of
higher-than-normal sea surface heights (warmer-than-normal sea surface temperatures) between
180 degrees W and 130 degrees W. These types of events, should they continue and persist
into the fall, can herald the beginnings of an El Niño episode.
"Although an El Niño would be welcome in the American west which definitely needs the
rainfall, it's way too early to even begin talking about a possible El Niño," said JPL
oceanographer Dr. Bill Patzert. "Scientists will continue to monitor the Pacific closely
for further signs of possible El Niño formation and intensity," said Dr. Lee-Lueng Fu,
JPL Jason Project Scientist.
The image shows a red area in the central equatorial Pacific that is about 10 centimeters
(4 inches) above normal. These regions contrast with the eastern equatorial Pacific, where
lower-than-normal sea levels (blue areas) continue that are between 5 and 13 centimeters
(2 and 5 inches) below normal. Along the equator, the red sea surface heights equate to
sea surface temperature departures greater than one degree Celsius (two degrees Fahrenheit).
These images show sea surface height anomalies with the seasonal cycle (the effects of
summer, fall, winter, and spring) removed. The differences between what we see and what
is normal for different times and regions are called anomalies, or residuals. When
oceanographers and climatologists view these "anomalies" they can identify unusual
patterns and can tell us how heat is being stored in the ocean to influence future
planetary climate events. Each image is a 10-day average of data, ending on the date
indicated.
The U.S. portion of the Jason mission is managed by JPL for NASA's Earth Science Enterprise,
Washington, D.C. Research on Earth's oceans using Jason and other space-based capabilities
is conducted by NASA's Earth Science Enterprise to better understand and protect our home planet.
|