pacific_calm_000831 PASADENA, Calif. After three turbulent years, the equatorial Pacific Ocean has settled down, spelling an end to the El Nino and twin La Ninas that wreaked havoc with the climate, new
satellite measurements show.New data from the Franco-American TOPEX/Poseidon satellite show that tropical Pacific sea levels, which swell or shrink according to the amount of heat the water stores, have returned to near-normal levels after three years of ups and downs.
New data from the TOPEX/Poseidon satellite shows the Pacific is calming down after three years of turbulent La Ninas and El Ninos.
However, a NASA oceanographer warned that its not curtains for El Nino and La Nina.
"Itll come back, I always say its not adios, its hasta la vista," said Bill Patzert, a research oceanographer at NASAs
Jet Propulsion Laboratory (JPL).Persistent turbulence
Indeed, persistent turbulence in some areas of the ocean could mean longer-term effects on global weather.
In the latest satellite images, acquired over a 10-day period ending August 17, normal sea levels are shown in green. In images, cooler waters are blue to purple, indicating they are about 6 inches (14 centimeters) lower than normal. Warmer are red to white, indicating they are about 8 inches (20 centimeters) higher than normal.
Sea height, in turn, gives an indication of the ocean water's temperature, with warmer water generally higher than cooler.
"The tropical Pacific has indeed returned to near-normal. Really, if you look at the large-scale patterns, there isnt much to talk about," said Vernon Kousky, a research meteorologist with the Climate Prediction Center in Camp Springs, Maryland "Were probably in store for something different from what we experienced in the last the years."
The present calming began in earnest three to four months ago, Patzert said. That marked the end of the period of unrest begun in 1997-98 with El Nino, followed by back-to-back La Ninas.
Warmer-than-normal winter
Kousky said the calmed Pacific would now mean a warmer-than-normal winter for much of the U.S. but that temperatures will still be cooler than they have been in the last three years.
Looking at the entire Pacific, a horseshoe of warm water in the far-western tropical Pacific and much of the northern and southern mid-Pacific still persists, however. That contrasts with the cooler water in the Bering Sea and the Gulf of Alaska, although both patterns are weakening.
~
Those patterns will likely cause La Nina-like atmospheric effects to persist, with the Western United States experiencing hot and dry weather and a larger than normal number of hurricanes for the Pacific and Atlantic, according to JPL.
El Nino and La Nina live on in other ways too. The spate of wildfires plaguing the country this season burn on thanks to the drier-than-normal weather. And, in many cases, those fires are fueled by the abundant vegetation that sprang up thanks to large amounts of rainfall brought on by previous El Nino and La Nina events over the past three years.
During the 1997-98 El Nino, for example, Los Angeles received about twice as much rainfall as normal, turning the parched Mediterranean scrub that rings the city, emerald green. In contrast, during 1998-99s La Nina, Los Angeles received about one-half its normal rainfall, while places like the Mt. Baker Ski Area in Washington received a whopping 95 feet (29 meters) of snow.
Its follow-on mission, Jason, is slated for launch from Vandenberg Air Force Base, California, on March 7, 2001, although that date will likely slip.
advertisement
