The Copernicus Sentinel-2 mission takes us over Alaska’s Columbia Glacier, one of many quickest altering glaciers on the planet.
Zoom in to discover this picture at its full 10 m decision or click on on the circles to be taught extra.
The Columbia Glacier, seen simply above the center of the picture, is a tidewater glacier that flows down the snow-covered slopes of the Chugach Mountains, which dominate the higher a part of the picture. The mountains maintain Alaska’s largest focus of glacial ice.
Because the early Nineteen Eighties, the Columbia Glacier has retreated greater than 20 km and misplaced about half of its complete quantity. This one glacier accounts for practically half of the ice misplaced within the Chugach Mountains.
The altering local weather is assumed to have induced its retreat. Till 1980, when its speedy and fixed retreat started, the glacier’s terminus was noticed on the northern fringe of Heather Island, which lies close to the top of Columbia Bay, the inlet into which the glacier at present flows earlier than draining into Prince William Sound. This satellite tv for pc picture, acquired in September 2023, exhibits as an alternative the deep principally ice-free Columbia Bay dotted with quite a few icebergs and fragmented sea-ice.
Relying on the quantity of sediment coming from the Chugach Mountains, water our bodies all through the picture will be seen in an array of colors: clear waters of the Pacific Ocean seem darkish blue, whereas turbid waters in inlets and glacial lakes seem in mild blue or cyan.
Columbia is simply one of many many glaciers affected by the results of local weather change. A lot of the glaciers world wide are dropping mass. Nevertheless, earlier than the appearance of satellites, measuring their retreat and finding out their vulnerability to local weather change was tough contemplating their dimension, remoteness and rugged terrain they occupy.
Totally different satellite tv for pc devices now can collect data systematically and over massive areas, offering an efficient means to observe change, hold observe of all calving levels and quantify the melting charge and their contribution to sea-level rise.
