The Arctic ice shelf has melted for the fourth straight year to its smallest area in a century, driven by rising temperatures that appear linked to a buildup of greenhouse gases. Scientists at NASA and the National Snow and Ice Data Center, which have monitored the ice via satellites since 1978, reported that the total Arctic ice in 2005 will cover the smallest area since they started measuring. It is the least amount of Arctic ice in at least a century, according to both the satellite data and shipping data going back many more years, according to a report from the groups. As of September 21, the Arctic sea ice area had dropped to 2.05 million square miles, the report said.
From 1978 to 2000, the sea ice area averaged 2.70 million square miles, the report said. It noted the melting trend had shrunk Inuit hunting grounds and endangered wildlife. The report warns that if melting rates continue, the summertime Arctic may be completely ice-free before the end of the century. The NSIDC, part of the University of Colorado at Boulder, helps NASA analyse satellite data.