The combined average global land and ocean surface temperatures for April 2009 ranked fifth warmest since worldwide records began in 1880, according to an analysis by NOAA’s National Climatic Data Center in Asheville, N.C.

The analyses in NCDC’s global reports are based on preliminary data, which are subject to revision. Additional quality control is applied to the data when late reports are received several weeks after the end of the month and as increased scientific methods improve NCDC’s processing algorithms.

Temperature Highlights

* April’s combined global land and ocean surface temperature was 1.06 degree F above the 20th century average of 56.7degrees F. The most significant warmth occurred in northern and northeastern Asia, Europe, and much of the planet’s southern oceans.

* The global combined land and ocean surface temperature of 55.8 degrees F is tied with 2003 for the sixth-warmest January-through-April period on record. This value is 0.97 degree F above the 20th century average.

* The global land surface temperature for April was 1.80 degrees F degrees above the 20th century average of 46.5 degrees F degrees.

Global Highlights

* Arctic sea ice coverage of 5.6 million square miles was the tenth-lowest April extent since satellite records began in 1979, according to the National Snow and Ice Data Center. This value is 2.8 percent below the 1979-2000 average. In contrast, the April Southern Hemisphere sea ice extent of 3.2 million square miles was 13.5 percent above the 1979-2000 average. April is early in the melt season for Arctic sea ice, and early in the growth season for Antarctic sea ice.

* Based on NOAA satellite observations, April snow cover extent was below the 1967-2009 average for the Northern Hemisphere. This marked the hemisphere’s sixth consecutive April with below-average snow cover extent. Warmer-than-normal conditions over Eurasia contributed to that region’s fourth-smallest April snow cover extent during the period. North American snow cover extent was slightly above average during the month.

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