The extent of sea ice in the Arctic is an important indicator for climate change, and the 2007 season has presented a record low in the extent. Map and trends have been updated from Global Outlook for Ice and Snow
There have been continous measurements of the extent of the sea in the Arctic Ocean since 1979, using various satellite surveys. Data from remote sensing shows that the September measurements for 2007 are the lowest in this time series, opening up the Northern Sea Route and the North West Passage, as well as exposing a large section of the Arctic Ocean. The September extent in 2007 was only 61% of the 1979-2000 average, and a long term trend shows a decrease of -10% per decade.
The extent of sea ice in the Arctic is an important indicator for climate change, that indicates the overall temperatures in the seas and in the air. In addition, sea ice represents a very important factor in the global climate system, reflecting incoming solar energy. With less ice, more solar energy is absorbed in the ocean, which increases the temperature further. Another aspect of the retreat of sea ice is new areas of the Arctic sea floor are easier to access for exploration, and shipping routes will be open for an extended season.
GRID-Arendal have updated graphics from the UNEP report Global Outlook for Ice and Snow, published June 2007, with the latest data for the year of 2007. The data was retrieved from the National Snow and Ice Data Center (NSIDC).