This video shows Arctic sea ice from March 7, 2011, to Sept. 9, 2011, ending with a comparison of the 30-year average minimum extent, shown in yellow, and the Northwest Passage, in red.

Okay this is another global warming effect. Don't think easy, this is a FACT guys! i have been read a book about the earth future. the book said that in 2020 there's no ice in the earth surface anymore. Some countries are sink because the increases of sea surface. Much diseases make almost 1/3 people in the world are dying. That awesome.. :'((