For First Decade of the 21st Century, U.S. Annual Temperatures Remain Above Normal

The U.S. National Oceanic and Atmospheric Administration (NOAA) released yesterday (8 January 2010) temperature and precipitation data for the year 2009.  The temperature for the continguous U.S. was above normal, continuing the unprececented series of 13 years with above normal temperatures -- and continuing the longer term warming trend.  The last year for which the temperature was below normal was 1996.

The long term temperature trend is an increase of  0.12oF / decade.  As indicated by the table below, the annual average temperature for the contiguous U.S. is 52.79oF -- and every year since 1996 has fallen above that average. 

For Alaska, which is not included in the above data, 2009 was the 20^th warmest on record, with a temperature 0.7°F (0.4°C) above the 1971–2000 average.   This is consistent with a long term warming trend in the state, with most years since the late 1970s recording well above normal temperatures.

In its 2009 Annual Climate Summary for Barrow, the U.S Weather Service provides a sense of the extraordinary changes occurring in the northern reaches of the state along the Arctic ocean:

"This year will also go down in the books as the 6th warmest on record.... Seven of the top ten warmest years have ...happened within the last ten years. Twenty temperature records were either set or tied in 2009... For the first time in station history the temperature during the months of July and August remained above freezing. A record streak of 68 consecutive days of above freezing conditions began 1 July continuing through August and finally concluded on the morning of 7 September ...The month of October ended up as the 3rd warmest with four temperature records set or tied. "

The warm Arctic conditions were coupled to near record declines in Arctic sea ice, and in September walruses were forced ashore where they gathered in large "haul-outs."  Conditions were ripe for stampedes and in late September many dead walruses -- mostly calves and yearlings -- were found on a beach southwest of Barrow. Government scientists concluded that “the cause of death was consistent with trampling by other walruses.”  (see Dramatic Footage Shows Consequences for Walruses as Arctic Warms, 2 October 2009).

Online Resources:

• National Climate Summary, Year-to-Date, January-December 2009.  From NOAA's National Climatic Data Center.  Updated 8 January 2010.
• 2009 Annual Climate Summary for Barrow.  U.S Weather Service, 4 January 2010.
• Looking for Above Normal Temperatures? They are in the Arctic.  WWF Climate Blog, 5 January 2010. 
• Don't be Fooled by Weather's Ups and Downs: The Climate is Warming -- Rapidly.  WWF Climate Blog, 24 December 2009. 
• It's Cold so There is No Global Warming.  Video "Climate Denial Crock of the Week" by Peter Sinclair, 16 January 2010.