SAN FRANCISCO
(Reuters) - El Nino and La Nina, the terrible twins blamed for
a spate of destructive weather patterns worldwide, have finally
dissipated. That's the good news.
The bad news:
Their impact on the weather will likely continue for some time
to come. That's the conclusion of National Aeronautics and Space
Administration (NASA) scientists based on the latest satellite
data gathered this month over the Pacific.
Armed with
this information, meteorologists at the National Oceanic and Atmospheric
Administration are sticking with earlier forecasts for continued
heat in the Western U.S. -- currently suffering its worst wildfire
season ever -- and an unusually active hurricane season in the
Atlantic and Pacific.
"It appears
that the global climate system is finally recovering from the
past three years of dramatic swings from the extra-large El Nino
of 1997/98, which was followed by two unusually cool and persistent
La Nina years," said William Patzert, an oceanographer at
NASA's Jet Propulsion Laboratory in Pasadena, Calif.
La Nina, Spanish
for "the girl child", is the term used to describe weather
patterns spawned by a vast body of abnormally cool water in the
Central and Eastern Pacific Ocean.
The term was
coined to describe the opposite phenomenon of El Nino, or "the
boy child", the name used for decades by South American fisherman
for a warming of the same waters, often around Christmas time.
"Unfortunately,
in the longer term, the reality is that the PDO (Pacific Decadal
Oscillation) pattern still dominates the Pacific and, in the short
term, the atmosphere is acting as though La Nina remains,"
Patzert said.
The Pacific
Decadal Oscillation refers to changes in Pacific Ocean temperature
patterns that wax and wane in cycles typically lasting 10 to 20
years.
While Pacific
water temperatures have gradually warmed over the past three to
four months to near normal in the tropics, the after effects of
La Nina are seen in persistent below-normal temperatures in the
Bering Sea and Gulf of Alaska.
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