Ocean circulation beneath Filchner-Ronne Ice Shelf from three-dimensional model results

A high-resolution three-dimensional ocean circulation model is applied to the cavity beneath Filchner-Ronne Ice Shelf (FRIS). The model predicts predominantly barotropic currents which form a series of cyclonic gyres in the deep basins and anticyclonic circulations around the islands. The surface circulation can be such that the water moves in the direction of decreasing or increasing ice thicknesses, in the former case leading to freezing, while melting at the ice shelf base results in the latter case. The pattern of melting and freezing is consistent with known distributions of marine ice and melting areas beneath FRIS. An anticyclonic circulation around the Korff and Henry Ice Rises with melting west of Korff Ice Rise and freezing on the eastern side and north of Henry Ice Rise is the main source for an ice-pumping mechanism that produces the observed large marine ice body in the central Filchner-Ronne Ice Shelf. The estimates for net melting for realistic conditions at the open ocean boundary are 40-50 km(3) yr(-1) indicating that ice shelf-ocean interaction is an important contribution to the mass balance of the ice shelf.