when you picture Antarctica, you probably see vast white ice stretching evenly into the distance. But below all that ice, the terrain is surprisingly rugged, which could have serious consequences for how the continent's glaciers melt.

That's according to a recent paper published in the journal Geophysical Research Letters. In the paper, a team of scientists reported that they'd discovered three massive canyons in the land beneath Antarctica's ice.

"Massive" is no understatement: The largest of the three is more than 200 miles long, its width in places spanning 20 miles, and certain parts more than a mile deep. The scientists named it "Foundation Trough." The other two aren't anything to sniff at, either: One is 180 miles long and the other 90 miles.

"If climate conditions change in Antarctica, we might expect the ice in these troughs to flow a lot faster towards the sea," first author Kate Winter, a scientist at Northumbria University in the U.K., told the BBC. "That makes them really important, and we simply didn't know they existed before now."

To understand the landscape beneath Antarctica's ice, the scientists used a radar. Beams of light were shot at a surface, and the time it took for the signal to bounce back was measured, producing a map of the hidden terrain.

Winter and her colleagues were particularly interested in an area scientists dubbed the "bottleneck" zone, where the east and west Antarctic ice sheets come together.

Scientists suspected that if something triggered serious melting in the Antarctic, this area's geology would shape how that melting played out.

And the giant canyons mean it's probably true: They could act as channels, funneling melting water away from the continent and into the ocean. That would encourage the ice sheets to melt faster. That means scientists have even more reason to figure out what's below the ice, before the ice is gone