A classic example of the ice rivers descending the Alps, the Glacier des Bossons is one of the very few glaciers in the world which drop below the tree line. Following a local habit, it is named after the tiny French village located at its feet. This composite view (my camera was not wide-angled enough) was taken from the cable-car station at Aiguille du Midi (3842 m) while the two smaller insets are more distant views from an intermediate location above Chamonix.
The bottom right corner of the composite picture shows a patch of bare gravel due to the retreating frontline of the glacier (once it menaced the roads in the valley). So far, global warming has done little visible damage to this glacier thanks, no doubt, to its location on the cool western slopes of Mont Blanc. The situation is very different on the other side of this mountain range, just about 10 km away.
I want to keep this picture as a reference and a testimonial for the future.
Chamonix, France, September 15, 2007. See also: Courmayeur Glacier, Scenic Mont Blanc and Mont Blanc album.
A physicists note: Ice, the solid state of water is an extremely complex material. Regarding the above picture, perhaps the most important of its properties is that it flows. Imperceptibly if you just look at it, but fast enough if you set up some marks and keep watching for a few months. The Glacier des Bossons drops into the warm area below the tree line where the temperature exceeds the melting point of water for a major part of the year. Therefore, it is being continuously melted at its lower end, but manages to keep its shape because enough ice continues to flow in from the above. High up, the ice is being formed from the accumulated winter snow and then "cascades" down the slope in a majestic ultra-slow motion. Flowing glaciers are dynamic structures which maintain their form even though their substance is being continuously replaced. Other examples of such structures are vortices, tornadoes, rivers, etc. And living organisms, of course!
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