Arctic sea ice extent shrunk down to 2.0 million square miles (5.1 million square kilometers) in September 2013—18 percent below the 1981-2010 average, but larger than record low set in 2012.

In 2012, sea ice melted to a record-breaking minimum extent. At the end of the summer melt season, ice covered only about half of the average area it did from 1979–2000.