New satellite data indicate that March 2010 was the third warmest month since December 1978, compared to seasonal norms, according to researchers at the Earth System Science Center (ESSC) at The University of Alabama in Huntsville.

Powered by the most intense El Nino Pacific Ocean warming event since 1997-1998, the first three months of 2010 have all landed among the six warmest months in the satellite temperature record, which starts in December 1978.

While 2010 has been significantly warmer than normal when averaged across large areas (global, hemisphere or the tropics), it isn't setting records in the continental U.S. No month so far this year has been in the top 50 warmest months in the contiguous 48 states; March was the only the 79th warmest month on record in the "Lower 48."

By comparison, Canada and especially the Canadian Arctic islands saw March temperatures that were as much as 8.5 C (15.3 degrees Fahrenheit) warmer than seasonal norms.

March temperatures (preliminary)

Global composite temp.: +0.65 C (about 1.17 degrees Fahrenheit) above 20-year average for March.

Northern Hemisphere: +0.85 C (about 1.53 degrees Fahrenheit) above 20-year average for March.

Southern Hemisphere: +0.45 C (about 0.81 degrees Fahreneheit) above 20-year average for February.

February temperatures (revised):

Global Composite: +0.60 C above 20-year average

Northern Hemisphere: +0.73 C above 20-year average

Southern Hemisphere: +0.45 C above 20-year average

(All temperature anomalies are based on a 20-year average (1979-1998) for the month reported.)