Arctic sea ice volume - 1980-2012

Artic sea ice volume has dropped far faster than coverage. In September the ice that remains is down by nearly 80% from its volume in 1980. At current pace of volume loss, the first ice-free Arctic day could come in just a few years.
Source: ScientificAmerican
URL:     http://blogs.scientificamerican.com/guest-blog/2012/09/21/arctic-sea-ice-what-why-and-what-next/