The melt of the summer sea ice in the Arctic is dramatic. Each September, when the ice reaches its annual minimum, there used to be around 7.5 million sq km of ice. It is now regularly below 5 million sq km, and hit a record low of 3.6 million sq km in 2012. This downward trend is projected to continue as global temperatures increase, but somewhat erratically.

The year at which the Arctic first becomes ‘ice-free’ (traditionally defined as 1 million sq km) is much discussed by scientists and the media, but is often a controversial topic. Continue reading Predicting an ice-free Arctic summer →