Scientists Discover Massive Instability Under East Antarctica Glacier

(Bloomberg) -- An Antarctic glacier that contains enough water to eventually raise global sea levels by 5 feet has been melting dramatically in the last two decades, according to NASA-led research published today in the journal Geophysical Research Letters. The finding brings new attention to the eastern coast of the coldest continent. Scientists previously thought ice melt there was slower than on the disintegrating western peninsula. 

“These observations challenge the view of glacier stability in East Antarctica,” the authors write. 

Denman Glacier receded almost three miles during the period of study, 1996 to 2018. What makes the glacier particularly worrisome, the scientists say, is its massive size and the unusual shape of the land beneath it, which is divided into two flanks. Where Denman meets the sea, its eastern side is protected from warming water by a tall, rocky ridge. Its western flank is a sitting duck for higher-temperature currents washing in and melting ice. The land under many glaciers slopes downward from the interior of the continent to the sea. With Denman’s western flank, it’s the reverse. Its land falls as far as two miles below sea-level, which makes it both the planet’s deepest canyon on land—and much more susceptible to ice loss. The unusual slope extends almost 30 miles into the continent.

The new paper builds on a transformative discovery from December that “redefines the high- and lower-risk sectors for rapid sea level rise from Antarctica.” Both the paper published today and the work from December are expected to influence projections of sea-level rise for the coming centuries. The current highest emission scenarios project global seas rising by a cataclysmic 8 feet by the year 2100. 

The researchers plan to continue closely monitoring the glacier using Italy’s Cosmo-SkyMed satellites. 

©2020 Bloomberg L.P.