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CHALLENGES FOR THE FUTURE

The polar regions are unique in their biodiversity and wilderness values. Yet these are increasingly under threat from direct and indirect human impacts, especially global warming, tourism and long-range pollution.

There is a political will to address these and other polar issues and steps are being taken towards regulation and controls. The challenges of global warming and long-range pollution are much broader in their origins, but these too must be addressed if the polar environments are to remain stable.

Our Changing Environment
Arctic Seas: Shrinking ice cover

The extent of Arctic sea ice in September – the end of the summer melt period – is the most valuable indicator of the state of the ice cover. On average, sea ice in September covers an area of about seven million km2, a little smaller than the continent of Australia.

The scale indicates the per cent by which the local sea ice extent differs above or below the average for the period 1979–2000. The median ice edge for 1979–2000 is indicated by the black outer line. In 2002, total September ice extent was 15 per cent below this average. This represents a reduction equivalent to an area roughly twice the size of Texas or Iraq. From comparisons with records prior to the satellite era, this was probably the least

amount of sea ice that had covered the Arctic over the past 50 years.

Quite often, a ‘low’ ice year is followed by recovery the next year. However, September of 2003 was also extreme, with 12 per cent less ice extent than average. Calculations performed for 30 September 2004 show a sea ice extent loss of 13.4 per cent, especially pronounced north of Alaska and eastern Siberia.

Source: National Snow and Ice Data Centre News
http://nsidc.org/news/press/20041004_decline.html


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