SOURCE: Scientific American

DATE: November 6, 2017

SNIP: Significantly more ice in Greenland’s glaciers may be exposed to warming ocean waters than previously thought, new research suggests. Indeed, more than half the ice sheet may be subject to the melting influence of the sea.

These are the latest conclusions of a detailed mapping project exploring the topography of the seafloor and bedrock around and beneath Greenland’s glaciers.

Published in their final form last week in the journal Geophysical Research Letters, the maps draw on a variety of data sources, including satellite radar and aerial imagery, as well as special sonar data collected on ship expeditions to the front of the ice sheet.

Included in the new paper are some of the most detailed data yet on the depths of the canyons and fjords scarring the Greenland coast, which carry water in from the sea to lap against the ice. The results suggest that the western and northern regions of Greenland are most exposed to the influence of ocean water. Out of 139 ocean-touching glaciers the team identified, they also found that 67 rest in waters 200 meters (about 650 feet) or more below sea level, where warm water is typically found—at least twice as many as previously thought.