While most of us are well aware of the extent of the loss of glacial ice in both Greenland and the Antarctic, new findings from a composite of satellite surveys have discovered that the volume of ice loss has been so dramatic in Western Antarctica that it has changed the region’s gravitational constant.
While for the most part, the Earth’s gravitational pull is relatively the same all over the globe, minute variations in gravity exist, due to different thicknesses and densities in the Earth’s crust, variations that we otherwise wouldn’t notice. While it’s assumed that these variations in the gravitational field remain stable, data from the European Space Agency’s GOCE satellite, corroborated with data from Germany’s GRACE and ESA’s Cryosat satellites, have found that the sheer mass of ice loss from the Pine Island and Thwaites glaciers, and the Getz Ice Shelf, have caused a minute, albeit measurable, reduction in the gravitational field on that side of the continent. The change in the gravity map was also over a fairly short time period — 2009 through 2012 — underscores the rapidity of the ice loss.
The ESA plans to expand this investigation to include the rest of the Antarctic continent, in an effort to understand the ongoing phenomenon of ice melt, and hopefully to build a better predictive model for sea level rises.