Record Breaking Temperatures Continue in March for Southern Hemisphere

NASA reports that record high temperatures in the Southern Hemisphere persisted into March 2010, following the warmest summer (Dec-Feb) on record there -- and its hottest year on record in 2009.  NASA data indicates that globally, surface temperatures were the second highest on record in March.

The data, released by NASA's Goddard Institute for Space Studies, shows that the land-ocean temperature index for the Southern Hemisphere was 0.62oC above the 1951-1980 mean for March.  The previous March record, set in 2002, was 0.61oC above the mean.  Globally, March surface temperatures were 0.84oC above the global mean for 1951-1980 of 14oC.  The warmest March on record globally, March 2002, was 0.85oC. 

These differences between March 2002 and March 2010 are very small both globally and for the Southern Hemisphere.  The bottom line: March 2002 and 2010 are the hottest on record for the globe overall and for the Southern Hemisphere.

The temperature anomalies were particularly large and positive in the Arctic and Antarctic, Canada and the northern U.S., Scandinavia, and in the area stretching roughly from Tibet to the Atlantic waters off the coast of West Africa (see figure below).

One of the few areas with large negative temperature anomalies was the Bering sea, where sea-ice extent was above normal (see our earlier post, Thinner than Normal Arctic Sea Ice Poised for a Rapid Decline in 2010, 4 April 2010). 

Above: Global surface temperature anomalies, March 2010.  Source: NASA GISS.

Among the notable positive temperature anomalies in March were in the eastern tropical Atlantic -- the Main Development Region for Atlantic hurricanes (see figure below).  Sea surface temperatures there were at record levels for March.  Should the anomalies persist into the hurricane season, there will be more energy available for the formation of hurricanes.  The high temperatures -- along with an anticipated fading of the current El Nino in the tropical Pacific -- is cited by experts who anticipate a relatively active hurricane season (1 June through 30 November) in 2010.

Above: Sea surface temperature (SST) anomalies, western hemisphere, 12 April 2010.

U.S. Temperature Anomalies

Data released last week (8 April 2010) for the U.S. by the National Oceanic and Atmospheric Administration (NOAA) shows that surface temperatures in March for the contiguous U.S. were above normal, continuing a long trend of rising temperatures since 1950.

NOAA's data also confirms what the global map at the beginning of this posting suggests: the northern U.S. was anomalously warm while much of the southeast was below normal.

NOAA reports that "Rhode Island had its warmest March on record. It was Maine's second warmest March, New Hampshire's third warmest, and the fifth warmest for Massachusetts, Connecticut, New Jersey, Vermont, and Minnesota. Five other states (for a total of thirteen) also had a March average temperature among their ten warmest."  In addition, NOAA reports that "According to the Canadian Ice Service, mid-March ice coverage over the Great Lakes was at a record low - only 3.5 percent of the Lakes’ surface. The average ice extent for the period is roughly 31 percent of the Lakes’ surface. The record dates back to 1973."

Like NASA, NOAA also issues global surface temperature data.  As of this posting, that data had not yet been released for March.

Online Resources:

NASA Goddard Institute for Space Studies:

•  Northern Hemisphere Land-Ocean Temperature Index
• Southern Hemisphere Land-Ocean Temperature Index
• Global Land-Ocean Temperature Index

State of the Climate, National Overview, March 2010.  See also the press release (8 April 2010) from NOAA, NOAA: U.S. Averaged Warmer-than-Normal, Drier-than-Normal in March.

Record Atlantic SSTs continue; very active hurricane season foreseen by CSU and TSR.  From Jeff Masters, Wunder Blog, 12 April 2010.

WWF Climate Blog:

• Southern Hemisphere Summer is Warmest on Record; Dec-Feb Period is Second Warmest Globally
• Southern Hemisphere in 2009 Saw Warmest Year on Record
• Antarctica Losing More than 24 cubic Miles of Ice Annually -- and the Pace is Accelerating.  WWF Climate Blog (13 January 2010)