Geophys. Res. Lett. doi:10.1029/2010GL042496 (2010)

Rapid loss of floating sea ice is contributing a tiny amount, 50 micrometres, to the current annual global sea-level rise of around 3 millimetres.

Andrew Shepherd of the University of Leeds, UK, and his colleagues combined satellite observations with an ice–ocean model to estimate the floating ice lost between 1994 and 2004. They found that about 750 cubic kilometres of ice melted each year in the Arctic Ocean and off Antarctica. The melting and freezing of sea ice do have small effects on sea level, the authors say, because fresh water is about 2.6% less dense than sea water.