A WEAK EL NIÑO MAY BE PRESENT BY THE END OF THE MONTH
Nov. 6, 2003 — The world may soon be getting an early holiday gift. Scientists at NOAA are observing oceanic telltale signs the climate phenomenon known as El Niño may be back in a weak form just in time for the holidays. The November 6 release of NOAA Climate Prediction Center's monthly El Niño-Southern Oscillation (ENSO) Diagnostic Discussion reports warmer-than-normal surface and sub-surface ocean temperatures were observed in most of the equatorial Tropical Pacific in the month of October 2003. (Click NOAA satellite image for larger view of developing El Niño in the tropical Pacific Ocean taken on Nov. 3, 2003, which is represented in red on the western coast of South of America. Click here to view latest satellite image. Please credit “NOAA.”)
"Based on the sea surface temperature observations for September, October, and those projected for the rest of November, as well as the NOAA definition for El Niño events, there is an above average likelihood sea-surface temperature conditions will be characterized as a weak or borderline El Niño by the end of November," said Vernon Kousky, lead ENSO scientist at NOAA. It is likely warmer-than-average conditions (borderline El Niño/ ENSO-neutral) will persist in the equatorial Pacific through the Northern Hemisphere winter of 2003-04. However, at this time, CPC does not anticipate major impacts from this event on U.S. winter weather.
NOAA defines El Niño as a phenomenon in the equatorial Pacific Ocean characterized by a positive sea surface temperature departure from normal (for the 1971-2000 base period) in the Niño 3.4 region greater than or equal in magnitude to 0.5 degrees C, averaged over three consecutive months. The last El Niño occurred during the period from May 2002 through March 2003. It is unusual, but not unprecedented, to have El Niño conditions during two successive winter seasons.
El Niño, which means the "Christ Child" in Spanish, originally signified the annual appearance of warm waters along the coasts of Ecuador and Peru that occurred near Christmastime. Fishermen along the coast of Ecuador and northern Peru were aware of this phenomenon and coined the term. The term El Niño now refers to a more extensive abnormal warming of the tropical Pacific waters that sometimes extends from the South American coast westward to near New Guinea in the west Pacific. This more extensive warming can have major impacts on temperature and precipitation patterns throughout the world.
NOAA will continue to monitor the fluctuation and changes in sea-surface and sub-surface temperatures and issue weekly and monthly updates via the CPC Web site. Also, NOAA will issue a U.S. Winter Outlook update via the NOAA home page on Nov. 20, 2003.
Diagnostic Discussion is published monthly by CPC and is a consolidated
effort of NOAA and its funded institutions. The CPC predicts and monitors
El Niño/La Niña and also produces the nation's official
long-range outlooks and extended range forecasts.