A while back PBS covered the issue in the interview below.
In this article from Chomsky called Issues that Obama and Romney Avoid Chomsky talks about how prior projections had been that we might see summers without Arctic ice by the end of this century. Now it could be as early as 2020? And the response is not alarm from our politicians and world leaders. It's how do we exploit newly exploited territory for more oil and other materials. This will accelerate the problem.
As discussed in the interview, the ice caps are like the earth's air conditioners. They reflect tons of solar radiative heat. With the ice gone and water in its place more heat will be absorbed. We're in big trouble here. Things are already grim for the poor in Africa thanks to the drought from this year. Meanwhile our politicians are focused on who can talk the toughest about Iran.