Mass balance of the Antarctic ice sheet at Patriot Hills

Abstract

Glaciological data collected at Patriot Hills, Antarctica (80°18' S, 81°22'W), are used to assess the local mass balance of the ice sheet. The data were collected during two field campaigns conducted by the Instituto Antartico Chileno in January and November 1995. Measurements included surveying of stakes, and ice thickness derived from discrete radar soundings with a ground-based high-frequency impulse system. Ablation occurred on the bare-ice field at the base of Patriot Hills, with a maximum value of 7 g cm-2 a-1. Net accumulation was detected away from the mountains, over the firn-covered area of the glacier, with a maximum rate of 10 g cm-2 a-1. Ice thickens rapidly away from the mountains, reaching a thickness of 383 m, the maximum range of the radar system, near the center of the blue-ice field. No significant difference in surface elevation of the ice was detected over the 305 d period, which indicates that the ice is in near-equilibrium at Patriot Hills.