Aletsch Glacier in Switzerland

December 01, 2011

Great Aletsch Glacier (2)

Photographer: Piero Armando
Summary Authors: Piero Armando; Jim Foster

December 2011 Earth Science Picture of the Day Viewer's Choice The photo above showing the sinuous Aletsch Glacier was captured from near the summit of Eggishorn (9,600 ft or 2,926 m), in the eastern Bernese Alps. The Aletsch Glacier is the longest glacier in the Alps Mountains, stretching to a length of nearly 14 mi (23 km). Note the chalky band of rock between the glacial ice and the zone of vegetation (green) on the far side of the valley -- clear evidence that this glacier is in retreat. Between 2005 and 2006 alone, the Aletsch Glacier receded approximately 330 ft (100 m). Medial moraines, formed when glaciers merge, line the Aletch Glacier. The debris signature of such mergers is often carried many miles downstream. Photo taken on July 20, 2010.

Photo details: Canon EOS 30D camera; 17mm focal length; f/11.0 aperture; 1/250 sec. exposure; ISO equivalent 100; sRGB color space; two separate exposures stitched together.