Information Page: Glacier Calving
Block Calves of Glacier Front
|Model name:||Animation model name|
|Where:||Disko Bay, Greenland|
|When:||< 1 min|
Statement: Block calves of a glacier front in Disko Bay, Greenland
Abstract: One can see a big block calving of a tidewater glacier front. A tidewater glacier ends in a body of water, in this case Disko Bay in Western Greenland. The ice that calves of the glacier front forms floating icebergs. Calving happens rapidly. One can often hear a crackling or booming noise and then see the ice tumble into the ocean. The ice mass can be extremely large, and this produce significant waves. This movie was made from a boat sailing through the fjord.
A calving glacier (also called tidewater glacier) is a glacier that ends in a body of water. Calving glaciers occur in Alaska, Arctic Canada, Patagonia, as well as along the Greenlandic Ice Sheet and Antarctica. It is these systems that produce icebergs floating in the world oceans.
Calving glaciers behave very differently than land-based glaciers. Their velocity accelerates at the terminus, and they are much more dynamic than land-based glaciers. Calving glaciers need a large accumulation area to compensate for the ice mass lost by calving. Calving rates of tidewater glaciers in Alaska were found to be controlled by the depth of the water at the glacier front (Brown et al., 1982).
Vc = calving speed (m/yr) C = calving coefficient (27.1 +/- 2 per yr for a study of 13 Alaskan glaciers) Hw = water depth at the glacier front (m) D = constant (0 m/yr for a study of 13 Alaskan glaciers)
Calving glaciers can advance and retreat at great rates. Some of the Alaskan calving glaciers retreated over > 100 km in the last two centuries.