This is an excerpt from EERE Network News, a weekly electronic newsletter.

March 21, 2007

NOAA: This Winter was the Warmest on Record for the Globe

Global temperatures for December 2006 through February 2007 were the warmest on record, according to the National Oceanic and Atmospheric Administration (NOAA). El Niño conditions contributed to the season's record warmth, which was 1.3 degrees Fahrenheit above the mean temperature for the 20th century. Temperatures were above average across the globe, with the exception of Saudi Arabia, Iraq, and some areas in the central United States. In fact, the cooler central U.S. temperatures helped keep overall U.S. temperatures near average for the winter. NOAA also noted that the El Niño conditions rapidly weakened in February. See the NOAA press release and the report on global temperatures from NOAA's National Climatic Data Center.

With the El Niño conditions weakening, NOAA warned in late February that sea surface temperatures were indicating a possible transition to a La Niña event, which involves cooler-than-normal sea surface temperatures in the central and east-central equatorial Pacific. This is bad news for this year's hurricane outlook, since La Niña events tend to result in a greater number of hurricanes in the Atlantic Ocean. In contrast, El Niño events create wind shear over the Atlantic Ocean, which inhibits hurricane formation. This cycle explains the low number of hurricanes in 2006, but suggests a greater number of Atlantic hurricanes this year. In fact, back in December, researchers at Colorado State University (CSU) anticipated a weakening El Niño, and forecasted 14 named storms, seven hurricanes, and three major hurricanes this year. See press releases from NOAA and CSU and the CSU hurricane forecast.

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