The research was carried out by Germany’s Alfred Wegener Institute Helmholtz Center for Polar and Marine Research and published in the European Geosciences Union journal The Cryosphere. For the study, engineers attached a radar altimeter to the ESA’s orbiting satellite, CryoSat-2, and then monitored the planet’s ice sheets for three years.
The altimeter, known as SIRAL, has allowed scientists to produce the most detailed maps of land-based and floating ice formations to date. Veit Helm, the report’s lead author, says their new maps “cover close to 16 million square kilometers, which is 500,000 square kilometers more – about the size of Spain – than previous elevation models from altimetry.”
The research team compared SIRAL’s data to measurements taken by NASA’s ICESat satellite (which ended its mission in 2010) and found that the Greenland and Antarctic ice sheets are melting at a combined rate of 500 cubic kilometers per year.
Though West Antarctica was found to be rapidly losing ice, East Antarctica is actually growing in volume. However, the buildup of ice on the eastern side of the continent cannot make up for the rate of loss, which researchers report as a net 125 cubic kilometers per year. Greenland’s ice is melting at 375 cubic kilometers per year.
“Since 2009, the volume loss in Greenland has increased by a factor of about two, and the West Antarctic ice sheet by a factor of three,” said Angelika Humbert, one of the report’s authors.
This rate of melt means that the ice sheets’ yearly contributions to ocean volume has doubled since 2009, confirming an earlier study by the Potsdam Institute for Climate Impact Research that predicted growing emissions levels would lead to faster sea level rise.