Agence France Presse: Arctic sea ice is melting "significantly faster" than predicted and is approaching a point of no return, conservation group the World Wildlife Fund (WWF) warned in a new study. The volumes of the Greenland Ice Sheet and ice in the Arctic Ocean were estimated at 2.9 million and 4.4 million cubic metres respectively in September 2007 — the lowest ever levels recorded, the organization said Wednesday. The sea ice shrank to 39 percent below its 1979-2000 mean volume, it …