A hydromechanically coupled flowline model for simulating glacier surge behaviour of land-terminating, hard-bedded, temperate glaciers

Glacier surge behaviour is characterized by multiyear, quasi-periodic changes in glacier geometry and ice flow. Various attempts have been done on modelling glacier surge behaviour. The focus of this research will be on land-terminating, hard-bedded, temperate glaciers (LHT-glaciers). Whereas the drainage system at the base of the glacier is thought to be the key element in the surge behaviour of those glaciers, developed models do not include a basal drainage model. The surges of LHT-glaciers are characterized by a sudden initiation and a sudden termination of the surge. This sudden on- and offset is assigned to switches in basal drainage system. Therefore, a description of the transformation of the basal drainage system during a surge cycle of LHT-glaciers is proposed. The proposed transformation is based on observations of the 1982-1983 surge of Variegated Glacier, Alaska. Despite the fact that models that are capable of simulating quasi-periodic behaviour related to basal frictional lubrication do not include a basal drainage model, building blocks of a basal drainage model for surging glaciers have been proposed for a long time. By means of translating the proposed transformation of the basal drainage system into those building blocks, a basal drainage model is constructed. The constructed basal drainage model is coupled to the ice mass continuity equation. By means of implementing the coupled model, it is shown that the model simulates the characteristic features of the surge cycle of LHT-glaciers.Environmental FluidmechanicsHydraulic EngineeringCivil Engineering and Geoscience