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Despite cold temperatures in much of North America (including record-breaking cold in Florida), northern Europe, and northern Asia, global average temperatures in December 2009 were the 8th warmest on record, according to preliminary data posted earlier this afternoon by the National Climatic Data Center (NCDC). Although global land temperatures averaged the least amount above average since 2002, ocean temperatures were second warmest only to 1997, reflecting at least in part a strengthening El Niño pattern in the equatorial Pacific. The El Niño pattern is expected to continue through spring 2010. For 2009 as a whole, the global average temperature was tied with 2006 as the 5th warmest calendar year.
Regionally, temperatures were cooler than average in most of the contiguous United States, southwestern and south central Canada, the U.K., Ireland, northern Kazakhstan, Mongolia, northern China, and most of Russia. In the Southern Hemisphere, New Zealand, Argentina, and southern Chile were all cooler than normal. Temperatures were warmer than average in Alaska, eastern Canada, Australia, eastern Russia, southern Europe, southern Asia, and parts of northern Africa and northern South America. For the entire year, most areas were warmer than normal; exceptions were: central Russia, southern Canada, north central contiguous U.S., the higher-latitude southern oceans, and along the eastern North Pacific Ocean.
Images (click to enlarge): December 2009 global temperature departures from average, global December temperature history, 2009 annual global temperature departures; all from NCDC
2 days ago