Greenland has melted all the way to bedrock before, and it could happen again—especially if we keep pouring carbon into the air like there’s no tomorrow. Now, scientists have released a detailed map showing what the vast ice island would look like if it shed all of its ice.
A disturbing prospect, but the images sure are lovely.
Greenland Basal Topography BedMachine v3 is now the most complete 3D map of the land beneath the Greenland ice sheet. It was assembled by researchers at the British Antarctic Survey, the University of Bristol, and the University of California, Irvine, based on airborne survey data from two NASA-led missions, Ocean Melting Greenland and Operation IceBridge, that was synthesized and published in a research paper last month.
The map offers a preview of the sort of landscape a future human hiking across an ice-free Greenland can expect to encounter, from rugged, channel-incised mountains along the island’s eastern and southern shorelines to relatively low, flat terrain toward the interior. Travelers would gain elevation again trekking toward the vast, glacier-carved fjords along the Greenland’s west coast.
Future backpacking adventures aside, this map is important for science because it “gives... a bird’s eye view of the fringes of Greenland which are experiencing the most changes,” according to BAS cartographer Peter Fretwell.
“This map will improve our understanding of the ice-ocean interactions and how the ice sheet will evolve in a changing climate,” Jonathan Bamber at University of Bristol added.
Indeed, as Earther reported recently and these maps makes clear, many of Greenland’s coastal outflow glaciers are deeply rooted, making contact with the bedrock over 200 feet below sea level. From an ice melting perspective, that’s bad. More deeply-rooted glaciers are exposed to warmer waters, hastening their melting. In order for these thick icy slabs to lose contact with that heat source, they often have to retreat very far inland.
With a refined picture of Greenland’s bedrock topography, the recent study estimated that global sea levels will rise about 7.42 meters (24 feet) if the ice sheet melts completely.
That process of melting is already well underway. Between 2011 and 2014, Greenland shed 1 trillion tons of water.
I’m getting this map because I’m a nerd and because it would go nicely with my growing space tourism poster collection. But unlike posters of Saturn’s moons, this map does more than inspire. It reminds us how precarious our planet’s cryosphere is, and how quickly Earth’s coastlines could be reshaped by changes that occur seemingly a world away.
You can purchase the map for yourself here.