Scientists see new signs of El Nino
CAMP SPRINGS, Maryland (CNN) -- A "steady evolution" of warming
temperatures in the mid-Pacific Ocean is pointing to the possible return
of El Nino later this year, scientists say. Further evidence in the next
few weeks would solidify the prediction.
"This warming represents an early stage of El Nino's onset. If the
warming persists, it will be several more months before mature El Nino
conditions develop," said Vice Admiral Conrad C. Lautenbacher Jr., head
of the National Oceanic and Atmospheric Administration.
Data from an array of heat-sensing satellites and a network of
monitoring buoys across the Pacific shows sea-surface temperatures have
jumped roughly 2 degrees Celsius -- from slightly below normal to
slightly above normal -- in the past year, NOAA said.
Past climate records suggest such a change often precedes the onset of
El Nino conditions, in which the warming ocean triggers a chain-reaction
of weather changes -- altering ocean currents, wind, weather and
rainfall patterns over much of the world.
In the 1997-98 El Nino, drought triggered catastrophic forest fires in
Indonesia; a warm, rainy winter in California was marked by a series of
storms that kicked off coastal mudslides; warm, wet weather also covered
the Southeast United States; and fishermen, sea lions, and seabirds
along the Pacific Coast from Peru to British Columbia suffered as fish
populations left for cooler waters.
El Nino conditions typically last one or two years, and are usually
followed by "La Nina" -- in which a cooling of those same mid-Pacific
waters triggers a complete reversal of climate impacts. Indonesia, for
example, suffered from three years of La Nina-inspired heavy rains after
the 1997-98 drought.
The climate phenomenon got its name from Peruvian fishermen, who noticed
an impact on their catch from the warming waters during the Christmas
season, when they were celebrating the birth of "El Nino" -- the Christ
child.
NOAA climatologist Vernon Kousky raised the latest warning in
mid-January, noting an abrupt warming of temperatures in the waters of
the Pacific Ocean near the equator. A handful of scientists agreed,
while many other climate experts demurred, saying it was much to soon to
declare El Nino to be under way.
Tuesday's NOAA announcement adds some weight to Kousky's prediction, but
virtually all climate experts agree that it's still much too soon to say
an El Nino will come, or how severe it will be.
Statistically, it's unlikely that a 2002 El Nino would match the severe
impact of the 1997-98 episode. An El Nino that severe tends to happen
only once or twice per century, according to climate experts.
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