NOAA State of the Climate 2010

• For 2010, the combined global land and ocean surface temperature tied with 2005 as the warmest such period on record, at 0.62°C (1.12°F) above the 20^th century average of 13.9°C (57.0°F). 1998 is the third warmest year-to-date on record, at 0.60°C (1.08°F) above the 20^th century average.

• The 2010 Northern Hemisphere combined global land and ocean surface temperature was the warmest year on record, at 0.73°C (1.31°F) above the 20^th century average. The 2010 Southern Hemisphere combined global land and ocean surface temperature was the sixth warmest year on record, at 0.51°C (0.92°F) above the 20^th century average.

• The global land surface temperature for 2010 tied with 2005 as the second warmest on record, at 0.96°C (1.73°F) above the 20^th century average. The warmest such period on record occurred in 2007, at 0.99°C (1.78°F) above the 20^th century average.    

• The global ocean surface temperature for 2010 tied with 2005 as the third warmest on record, at 0.49°C (0.88°F) above the 20^th century average.

• In 2010 there was a dramatic shift in the El Niño–Southern Oscillation, which influences temperature and precipitation patterns around the world. A moderate-to-strong El Niño at the beginning of the year transitioned to La Niña conditions by July. At the end of November, La Niña was moderate-to-strong.

NOAA, NCDC State of the Climate, Global Analysis, Annual 2010