NOAA reports global land and ocean surface temperatures in 2009 tied with 2006 as the fifth-highest on record, 1 degree above the 20th-century average. The decade was the warmest on record, beating the 1990s by 0.2 degrees. Arctic sea ice in December fell 6.6 percent below the 30-year average, the fourth-lowest since records began in 1979. There were short-term cool signals, too. Northern Hemisphere snow cover in December was the largest since satellite records began in 1967.

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