New Delhi, Friday, September 21, The Arctic sea ice, a key indicator of climate change, melted to its lowest level on record this year before beginning its autumnal freeze. The extent of ice probably hit its low point on September 16, when it covered 1.32 million square miles (3.42 million square km) of the Arctic Ocean, the smallest amount since satellite records began 33 years ago. Changing weather conditions could further shrink the extent.
The record was broken on August 26, when the ice shrank below the record set in 2007. After that, it kept melting for three more weeks, bringing the ice extent - defined as the area covered by at least 15 percent ice - to nearly half of the 1979-2000 average.
While we have long known that as the planet warms up, changes would be seen first and be most pronounced in the Arctic, few of us were prepared for how rapidly the changes would actually occur.
The summer ice is not just dwindling. It is also thin, relatively fragile seasonal ice instead of the hardier multi-year ice that can better withstand bright sunlight.
The Arctic is a potent weather-maker for the temperate zone, and is sometimes dubbed Earth's air conditioner for its cooling effects. However, as ice wanes and temperatures rise in the far north, the Arctic could add more heat and moisture to the climate system.
