Ice Divide Migration in Franz Josef Land

Migrations of ice divides within complex glacier systems are sensitive to changes in individual glacier regimes (i.e., glacier geometries, shapes, or balances). Ice divides, or boundaries of divergent ice flow, as well as glacier extents for several glaciers in the Franz Josef Land archipelago were mapped using historic topographic maps and satellite imagery over the past three decades. Observed movements in the position of the ice divides are thought to be influenced by changes in the external boundaries of the glaciers. Such changes in the position of ice divides in return influence changes in glacier geometries by altering the direction of ice flow. This study examines the dynamics of changes in ice flow, glacier extent, and ice divide location by incorporating each into a finite difference model for ice flow. Results from the ice flow model depicting the relationship between ice divides and glacier extents as well as the sensitivity of ice divide migration to glacier extent will also be presented.