(CNN)The sea ice off the coast of northern Greenland is normally some of the thickest in the entire Arctic, with ridges of ice piled as high as 70 feet in some places.
And despite the rapid retreat of sea ice across the region due to climate change, this harsh corner of the globe was expected to be the last to retain year-round sea ice cover.
But recent satellite imagery shows that some of the Arctic’s oldest ice has been replaced by miles of open water for the first time on record, surprising scientists and ice monitors.
