December 8, 2010
Midtdalsbreen Glacier, Norway retreat Continues in 2010
Posted by Mauri Pelto
The Norwegian Water Resources and Energy Directorate is the most extensive national glacier monitoring program in the world. They noted in 2010 that 27 of 31 glaciers monitored retreated. Midtdalsbreen near Finse drains the eastern portion of the Hardangerjøkulen (Hardanger ice Cap). This glacier retreated 34 meters from 2009 to 2010 and has retreated 143 meters in the last 10 years. This retreat is less than the retreat of Rembesdalsskaka Glacier which drains west from the Hardangerjokulen and has retreated 311 meters in the last decade. The 2010 Image below indicates the area beyond the terminus that is quite fresh and lacks any new vegetation as yet, the small hillocks and ridges are ice cored. The debris has not stabilized yet. The terminus is quite lacking in crevasses and the slope modest, suggesting the retreat will be ongoing. Beyond the current margin are a series of low moraines some of them forming annually with no retreat from October-May and then summer retreat. Moraines like this tend to be ice cored when formed and are prominent. The moraine is really a 20-50 cm or debris overlying a core of dirty ice. Once this ice melts years later the once obvious moraines are hardly noticeable. The terminus of the glacier is well defined. The upper section of the glacier that drains the ice cap lacks clear margins. The ice cap generally does retain snowpack throughout the summer season, continuing to feed the glacier outlets. The reduction in the area and depth of this seasonal snowpack by summers end leads to less outflow from the ice cap through the outlet glaciers and hence terminus retreat.