These data, taken during a 10-day collection cycle ending August 18 by the TOPEX-Poseidon mission,
2001, show that above-normal sea-surface heights and warmer ocean
temperatures (indicated by the red and white areas) still blanket the
far-western tropical Pacific and much of the north (and south)
mid-Pacific. Red areas are about 10 centimeters (4 inches) above normal;
white areas show the sea-surface height is between 14 and 32 centimeters
(6 to 13 inches) above normal.
This build-up of heat dominating the Northern and Western Pacific was
first noted by Topex/Poseidon oceanographers almost three years ago and
has outlasted the El Niño and La Niña events of the past few years. (See
http://www.jpl.nasa.gov/elnino/990127.html.) This warmth contrasts with
the Bering Sea, Gulf of Alaska and Eastern tropical Pacific where
lower-than-normal sea levels and cool ocean temperatures continue
(indicated by blue areas). The blue areas are between 5 and 13
centimeters (2 and 5 inches) below normal, whereas the purple areas
range from 14 to18 centimeters (6 to 7 inches) below normal. Across the
tropics, the equatorial ocean remains calm with no indication of any El
Niño developing.
Looking at the entire Pacific basin, the Pacific Decadal
Oscillations warm horseshoe in the North and West Pacific and cool
wedge pattern in the Eastern Tropical Pacific still dominates this
sea-level height image. Most recent National Oceanic and Atmospheric
Administration sea-surface temperature data also clearly illustrate the
persistence of this basin-wide pattern. They are available at
http://psbsgi1.nesdis.noaa.gov:8080/PSB/EPS/SST/climo.html.
Image Courtesy Topex Poseidon Team, NASA JET Propulsion Lab and the Centre National dEtudes Spatiales