According to Wikipedia, the albedo (a measure of the reflective ability of a surface) of snow is about 0.8 to 0.9. This means that snow-covered glaciers can reflect back about 80% to 90% of the energy from the sun’s rays. So when ice on glaciers melts, the reflective properties of the glaciers are lost. The earth beneath the ice sheets gets uncovered. The glacier then absorbs more heat, which in turn causes more of its ice sheets to melt away. The result is reduced glacier mass.
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