Sea Ice Extent

July's Northern Hemisphere
Sea Ice Extent plot

According to the National Snow and Ice Data Center, the July 2008 Northern Hemisphere sea ice extent, which is measured from passive microwave instruments onboard NOAA satellites, was below the 1979-2000 mean. This was the fourth least July sea ice extent on record. The previous three years had the least July sea ice extent since records began in 1979, with 2007 having the least July sea ice extent (19.5 percent below the 1979-2000 mean) on record. Sea ice extent for July has decreased at a rate of 6.1 percent per decade (since satellite records began in 1979) as temperatures in the high latitude Northern Hemisphere have risen at a rate of approximately 0.37°C per decade over the same period.

July's Southern Hemisphere
Sea Ice Extent plot

Meanwhile, the July 2008 Southern Hemisphere sea ice extent was above the 1979-2000 mean. This was the tenth largest sea ice extent in July (1.2 percent above the 1979-2000 mean) over the 30-year historical period. Sea ice extent for July has increased at a rate of 0.7 percent per decade.

For further information on the Northern and Southern Hemisphere snow and ice conditions, please visit the NSIDC News page, provided by the NOAA's National Snow and Ice Data center (NSIDC).

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