The image pair above shows part of Greenland along Melville Bay (a sub-section of Baffin Bay) on September 3, 2000, and September 21, 2021. The images were acquired with the Enhanced Thematic Mapper Plus (ETM+) on Landsat 7 and the Operational Land Imager (OLI) on Landsat 8, respectively. (Note that Earth Observatory originally published a version of the 2000 image in false color. Both images above are natural color and show a slightly wider view.)
The images show a 80-kilometer (50-mile) stretch of coastline. Like so many places around the edges of Greenland, a series of glaciers here carry ice from the island’s interior toward the coast and onto the ocean. Most of these marine-terminating glaciers are retreating. Kjer and Hayes—the two main outlet glaciers shown above—are also speeding up.
Notice that in 2000, Kjer Glacier abutted a few rocky outcrops. These rocks helped buttress the ice and slowed its oceanward flow. Then sometime in 2012, the glacier’s floating ice shelf disintegrated. The rocks became free-standing islands, surrounded in the 2021 image by open water and a mixture of sea ice and icebergs, or mélange. Having lost contact with the rocks, the glacier’s inland ice can flow even more rapidly toward the ocean.
According to Alex Gardner, a snow and ice scientist at NASA’s Jet Propulsion Laboratory, data from the NASA MEaSUREs project ITS_LIVE show that one year before the ice shelf’s breakup, the glacier flowed at an average speed of 1,200 meters per year. By 2018, the glacier’s average speed was more than 4,000 meters per year....
