Glob. Planet. Change 65, 83–88 (2009)

Global warming causes sea levels to rise in two ways: by melting land ice and by thermally expanding ocean water. In the past, the two factors have proved difficult to accurately tease apart, but Anny Cazenave of the Laboratory for Studies in Space Geophysics and Oceanography (LEGOS) in Toulouse, France, and her colleagues succeeded in measuring the two processes separately. They used gravity data from the GRACE satellites and temperature records collected by the Argo network of buoys.

They calculate that the thermal expansion of sea water has slowed recently and contributed only 0.3 millimetres per year to sea-level rise between 2003 and 2008. Meanwhile, melting land ice caused ocean levels to increase by about 2 millimetres per year.