Below the surface, the Petermann Glacier, one of Greenland’s largest, is actively melting–from beneath. Researchers at UCI and NASA’s JPL have discovered that the glacier’s grounding line–that is, the point where the glacier leaves its bed of land and extends into the ocean, responds to the tide. Surges in tide force warming water further into the glacier’s base between 2-6km, accelerating its melt rapidly. Consequently, between 2016-2022, the grounding line has retreated 4km inland. This research is significant as it shows that glaciers terminating beneath the ocean surface are not resistant to melting, as previously believed.

Dr Helen Millman, the new WEF Hoffmann Fellow on Polar Issues, highlights some of the catastrophic significance. According to Millman, “Projections of sea level rise from ice sheets could double as study shows that tidal action causes melt rate to increase dramatically. This means that we may be heading for the worst-case scenario for global sea level rise and hundreds of millions of people could be displaced by the end of this century.”

To learn more, check out this article.

Image was captured by NASA’s AQUA satellite in July, 2012.