Article Tags: World Temperatures
Sea ice extent for the past 5 years (in million km2) for the northern hemisphere, as a function of date.
Arctic Sea Ice Extent Highest in 6 Years
From the Copenhagen Centre for Ocean and Ice of the Danish Meteorological Institute
Total sea ice extent on the northern hemisphere since 2005. The ice extent values are calculated from the ice type data from the Ocean and Sea Ice, Satellite Application Facility (OSISAF), where areas with ice concentration higher than 30% are classified as ice.
The total area of sea ice is the sum of First Year Ice (FYI), Multi Year Ice (MYI) and the area of ambiguous ice types, from the OSISAF ice type product. However, the total estimated ice area is underestimated due to unclassified coastal regions where mixed land/sea pixels confuse the applied ice type algorithm. The shown sea ice extent values are therefore recommended be used qualitatively in relation to ice extent values from other years shown in the figure. In 2010 sea ice climatology and anomaly data will be available here.
H/T hockeyschtick.blogspot.com
Source: hockeyschtick.blogspot.com