Warming causes record Arctic ice melt

Driven by rising temperatures that appear linked to a build-up of greenhouse gases, the Arctic ice shelf has melted for the fourth consecutive year, U.S. scientists said on Wednesday.

Scientists at NASA and the National Snow and Ice Data Centre have been monitoring ice formation via satellites since 1978. Findings reveal that the total Arctic ice mass in 2005 will cover the smallest area since measuring began. It is the least amount of Arctic ice in at least a century, according to both the satellite data and shipping data.

As of September 21, the Arctic Sea ice area had dropped to 5.31 million square kilometres. From 1978 to 2000, the sea's ice area averaged 7 million square kilometres, the report said. Melting has reduced Inuit hunting grounds and endangered polar bears, seals and other wildlife.

The report warns that if the melting rate continues, the Arctic may be completely ice-free in the summertime before the end of the century, echoing last yearีs findings from the Arctic Council, an eight-nation report by 250 experts.

าItีs increasingly difficult to argue against the notion that at least part of what we are seeing in the Arctic, in terms of sea ice, in terms of warming temperatures ... is due to the greenhouse effect,ำ Mark Serreze, a research scientist at NSIDC, said in an interview.

Most scientists believe greenhouse gases, including carbon dioxide that is mainly released by cars and utility smokestacks, cause global warming by trapping solar heat in the atmosphere. Many believe global warming can lead to catastrophic consequences, including rising sea levels and strengthening weather events such as hurricanes.