It's been a while: On August 7, 2010 we climbed from Grindelwald (Swiss Alps) towards Schreckhorn hut to below the Rots Gufer. Our goal was to create first panorama photos for comparison photos of the glaciers of this region. When we were already back on the descent, we were able to observe and photograph an aesthetic and spectacular icefall of the Grindelwald Fiescher Glacier in the area of the rock face called Heissi Blatta.
Phase 1: Under loud noise, the ice on the rock, broken off at the edge, breaks into smaller pieces.
Phase 2: The smaller ice chunks flow down the rock face like water.
Phase 3: The broken ice is deposited on a cone at the foot of the rock face.
This process shows how glaciers grow or lose length and mass.
The yellow rectangle shows the area in which the ice collapse occurred. The glacial ice forms in layers above the break-off edge. The pressure of the ice mass ensures that the ice flows downwards and in this case breaks off above the edge of the rock.
If more ice flows in than melts further down, the glacier gains in length and mass. Over time, the cone below the rock face would become so high that the rock face would be covered with ice.
Currently, the situation is developing in the other direction: As a result of climate change, more ice is melting away below the rock face than is being formed at the top and breaking off over the rock face. In this case, the glacier loses length and mass.