The Melting of Sea Ice

There is a lot of news about the melting of Arctic sea ice and how we are on the brink of a disaster because of Global Warming. But I find that gloom-and-doom puzzling when I look at the following graphic showing an increasing sea ice spreading around Antarctica. It is even more puzzling because the news is filled with stories of Antarctic ice shelves breaking off and melting. How can they be melting away if the actual extent of the ice is increasing?

The above image is from the NSIDC site.

Here is a wonderful discussion (with lots of graphs) about ice ages and the effect of the sun given the orbital dynamics of the earth.