The unexpectedly rapid rebound of the Amundsen Sea Embayment (ASE) may help stabilize the West Antarctic Ice Sheet against catastrophic collapse, says a new study offering a rare silver-lining in glacier research. The marine portion of the WAIS accounts for a quarter of the world’s ice contribution to global sea level rise and is currently vulnerable to catastrophic collapse.
As glaciers and ice sheets ebb and flow, they deform the Earth’s crust. When loaded with icy weight, the crust is depressed, and as ice retreats, the surface rebounds like a spring, uplifting at a rate largely determined by the viscosity of the upper mantle underlying the region. This slow process is called glacial isostatic adjustment (GIA) and was thought to occur over a 10,000 year-timescale.
However, Barletta et al. now show that in fact, the ASE is undergoing one the fastest glacial isostatic uplift rates ever recorded – a 41 millimeters annually.