Possible causes of ice sheet thinning in the Mizuho Plateau

Abstract

To measure the horizontal and vertical movements and strain rates of the ice sheet surface in the Mizuho Plateau, East Antarctica, the Japanese Antarctic Research Expedition carried out the first triangulation survey on the network in November–December 1969 and a resurvey in December 1973–January 1974 along a route shown in Fig. 1 (see ref. 1). The surface slope¹ and accumulation rate² along the route were also measured. The route starts from point B fixed on rock in the Yamato Mountains and it traverses flow lines most of which are converging into the Shirase Glacier. The route is almost parallel to the equal elevation contours of the ice sheet surface except near points B and C. We report here the thinning of the ice sheet and discuss how it was caused.