Features of ice sheet flow in East Dronning Maud Land, East Antarctica

The Japanese Antarctic Research Expeditions (JAREs) have done glaciological studies on ice sheet dynamics and surface mass balance in East Dronning Maud Land, mainly around the Shirase Glacier drainage basin, during more than 30 years. The surface mass balance, obtained mainly by the snow stake method, was more than 250 mm/a in the coastal region, less than 50 mm/a in the inland region higher than 3500 m in altitude, and about 100 mm/a on average in the five drainage basins in East Dronning Maud Land. The ice flow velocity was observed around East Dronning Maud Land in three observation periods: on a route transversal to the Shirase Glacier flow in 1969 to 1974, along a route longitudinal to Shirase Glacier and a transversal route from Mizuho Station (70 degree 42'S, 44 degree 17'E, 2250 m a.s.l.) to the Soer Rondane Mountains area in 1982 to 1987, and along a route from S16 (69 degree 02'S, 40 degree 03'E, 554 m a.s.l.) near the coast to Dome Fuji Station (77 degree 19'S, 39 degree 42'E, 3810 m a.s.l.) in 1992 to 1995. Assuming steady ice flow, the balance velocity is calculated by integrating the surface mass balance in the upstream area from a specific point to the flow origin between adjacent stream lines. From the relation between balance velocity and basal shear stress, the basal sliding area was specified.