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

A high-resolution three-dimensional ocean circulation model is applied to t he cavity beneath Filchner-Ronne Ice Shelf (FRIS). The model predicts predo minantly barotropic currents which form a series of cyclonic gyres in the d eep basins and anticyclonic circulations around the islands. The surface ci rculation can be such that the water moves in the direction of decreasing o r 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 m elting and freezing is consistent with known distributions of marine ice an d 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-pum ping mechanism that produces the observed large marine ice body in the cent ral Filchner-Ronne Ice Shelf. The estimates for net melting for realistic c onditions 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 balan ce of the ice shelf.