Beneath Greenland’s massive ice sheet lies a landscape that looks nothing like the frozen white expanse visible today. Strip away the ice, and you’d find a giant bowl-shaped landmass with a deeply depressed interior, ringed by coastal mountains, carved by a mega-canyon longer than the Grand Canyon, and dotted with dozens of lakes. The terrain would also slowly rise over thousands of years as the land, freed from trillions of tons of ice, rebounded upward.
A Bowl-Shaped Interior With Mountain Rims
Greenland’s bedrock has been pushed down by the sheer weight of ice sitting on top of it for hundreds of thousands of years. Radar mapping shows the interior is scooped out like a shallow basin, with large portions sitting below current sea level. The coastal edges, by contrast, are ringed by mountain ranges that poke above the ice in some places today. Without ice, the center of the island would initially look like an enormous low-lying depression, possibly filled with seawater or freshwater depending on how connected it was to the ocean.
That depression wouldn’t last forever, though. Once the ice was gone, the land would slowly spring back upward in a process called post-glacial rebound. Modeling published in Scientific Reports estimates that Greenland’s central bedrock would eventually rise by up to 783 meters (about 2,570 feet), with an average uplift of around 301 meters across the island. That rebound would take thousands of years to complete, gradually transforming the sunken interior into higher ground.
A Mega-Canyon Longer Than the Grand Canyon
One of the most striking hidden features is a winding canyon buried beneath the northern part of the ice sheet. Discovered using NASA airborne radar data, it stretches at least 750 kilometers (460 miles), making it longer than the Grand Canyon. In places it plunges 800 meters (2,600 feet) deep, comparable to the deepest segments of its Arizona counterpart. The canyon has the characteristics of an ancient river channel, suggesting it was carved by flowing water long before the ice sheet formed. Without ice, it would be one of the most dramatic geological features on the planet.
Dozens of Hidden Lakes
An ice-sheet-wide survey using airborne radar identified 56 subglacial lakes beneath Greenland’s ice. Most sit in the northern and eastern regions, trapped between bedrock and the ice above. Some are stable and long-lived. Others are “active,” meaning they periodically fill and drain. A handful of smaller lakes near the ice sheet’s edges form seasonally, filling with meltwater in winter and draining during summer.
Without the ice sheet, many of these would become surface lakes of various sizes, scattered across the landscape. Combined with meltwater rivers flowing through valleys and the mega-canyon, ice-free Greenland would have a surprisingly water-rich interior rather than the barren rock desert some people imagine.
From Tundra to Boreal Forest
Greenland wasn’t always frozen. Sediment cores drilled from beneath 1.4 kilometers of ice at Camp Century in northwest Greenland contained preserved plant material, including moss stems and woody tissue. Chemical analysis of that plant matter is consistent with both tundra and boreal (subarctic forest) vegetation. Pollen records from nearby ocean sediment fill in more of the picture: during the Late Pliocene, roughly 3 million years ago, Greenland supported boreal forests in a humid, cool-temperate climate. As temperatures dropped heading into the ice ages, those forests gave way to tundra before the ice sheet eventually buried everything.
If the ice disappeared today, what grew back would depend on how warm the climate became. At minimum, you’d expect tundra grasses, mosses, and shrubs across much of the island. In a significantly warmer world, patches of forest with spruce and birch could return, particularly in the sheltered southern and coastal valleys where conditions would be mildest.
Why It Would Look Darker, and Why That Matters
Ice-free Greenland would be dramatically darker than it is today. Fresh snow reflects up to 85% of incoming sunlight back into space. Bare ice reflects less, around 57%, and once biological growth like algae takes hold on exposed ice surfaces, reflectivity can drop below 25%. Exposed rock and soil are darker still. This shift from a bright white surface to dark ground creates a powerful feedback loop: the darker surface absorbs more solar energy, which raises local temperatures, which accelerates further melting and warming. Observations from a 2021 atmospheric event over Greenland showed that bare ice exposure alone increased melting by 51% at mid-elevations compared to what would have happened with a snow-covered surface.
In practical terms, an ice-free Greenland would have a fundamentally different local climate. Summers would be warmer without a giant reflective ice sheet cooling the air. Coastal areas would likely experience more rainfall. The interior basin, once it rebounded, could develop its own weather patterns shaped by surrounding mountain ranges, much like other large islands.
What Happens to Sea Levels
Greenland’s ice sheet holds enough frozen water to raise global sea levels by about 7.4 meters (roughly 24 feet) on its own. That’s enough to submerge significant portions of coastal cities worldwide. For context, the U.S. Geological Survey estimates that melting all glaciers and ice caps on Earth, including Greenland and Antarctica, would raise seas approximately 70 meters (230 feet).
Greenland’s contribution alone would redraw coastlines around the globe. Major population centers like Miami, Shanghai, Amsterdam, and Dhaka would face severe flooding or complete inundation. The irony is that while Greenland itself would gain new land as its interior rebounded upward, much of the world’s existing coastal land would disappear beneath rising oceans. The island revealed beneath the ice would be a fascinating, rugged landscape of canyons, lakes, and eventually green valleys, but the cost of revealing it would reshape civilization far beyond Greenland’s shores.