Diurnal Frost-Heave Activity in The Sør-Rondane Mountains, Antarctica

Abstract

Measurements of diurnal frost heave and ground temperature were conducted on a humid debris slope in the Sør-Rondane Mountains, an inland ice-free area of East Antarctica. In the antarctic midsummer of 1987, diurnal freeze-thaw activity frequently occurred to form a diurnal active layer, the thickness of which had an influence on the amount of diurnal frost heave. Refreezing just after a thaw of more than 8 cm in depth produced a visible heave (≥0.2 mm), when the frozen layer seems to be supersaturated through water migration from the active layer. Further increase in the thaw depth also results in an increase in the amount of heave. The maximum heave (1.8 mm) during the measurement period occurred after the period of maximum thaw (15 cm in depth). Simple calculation based on cumulative diurnal frost heave in this period predicts the maximum potential frost creep rate on a 20° slope of about 5 to 7 mm yr^–1.