Pacific Recycles Last Year’s Winter
If you liked last winter, you’ll like this one. If not,
you won’t.
The Pacific ocean continues to be dominated by the
Pacific Decadal Oscillation, an above normal sea level pattern
that is larger and stronger than any El Nino/La Nina event,
according to the latest information from the U.S.-French
Topex/Poseidon ocean-monitoring satellite.
“It is striking how similar October 2001 looks to October
2000,” said Dr. William Patzert, an oceanographer at NASA’s
Jet Propulsion Laboratory, Pasadena, Calif. “Last winter the
weather- and moisture-delivering jet stream was steered north
by this pattern, resulting in a very chilly, stormy winter in
the Midwest and continuing drought on the West Coast.”
“Looks like a repeat performance to me,” Patzert added.
The Topex/Poseidon data were taken during a 10-day
collection cycle ending Oct. 29. They show that the near-
equatorial ocean has been very quiet during the past year, and
sea levels and sea surface temperatures are near normal.
Above normal sea surface heights and warmer ocean temperatures
still blanket the far western tropical Pacific and much of the
north mid-Pacific.
In the western Pacific, the buildup of the Pacific
Decadal Oscillation, first noted by Topex/Poseidon
oceanographers more than three years ago, has outlasted both
the El Nino and La Nina of the past several years. This
warmth contrasts with the Bering Sea, Gulf of Alaska and West
Coast, where lower than normal sea surface levels and cool
ocean temperatures continue.
“There will be winners and losers in the next few
months,” said Patzert. “The upper and lower Midwest should
expect intermittent blizzards, and the West Coast and
Southwest a continuation of below normal rainfall. The
outlook is not extreme nor catastrophic.”
These data are in line with the U.S. winter forecast
issued by the National Oceanic and Atmospheric
Administration’s National Weather Service. They also show a
repeat of last winter’s chill across the northern states and
relative warmth across the South, with continuing drought in
the southeastern states and possibly the western states.
“Next month’s launch of the Jason 1 satellite will
continue the revolutionary Topex/Poseidon data-gathering with
a smaller satellite based on new technologies,” said Dr. Lee-
Lueng Fu, the Topex/Poseidon and Jason 1 project scientist at
JPL. “It will further improve the understanding of ocean
circulation and global climate forecasts, as well as provide a
key step towards making sea surface height measurement a
permanent component of a global ocean observing system in the
future.”
The joint U.S.-French Topex/Poseidon mission and the
Jason 1 program are managed by JPL for NASA’s Earth Science
Enterprise, Washington, D.C. JPL is a division of the
California Institute of Technology in Pasadena.
For more information, see the following urls:
Topex/Poseidon — http://topex-www.jpl.nasa.gov
October 2001 Topex/Poseidon image —
http://www.jpl.nasa.gov/images/earth/pacificocean
Last year’s October pattern —
http://hail/Datasets/links/hail/air7/akh/TPimages/2000/o t2000_ball.gif .
NOAA seasonal weather forecasts —
http://www.noaanews.noaa.gov/stories/s794.htm
Jason 1 — http://sealevel.jpl.nasa.gov
