Analysing the development of meltwater networks on Antarctica

Abstract

Meltwater features play an important role in the stability of the Antarctic ice shelves. They can destabilize ice shelves by exerting additional loading forces due to the weight of the water concentrated on one location. However, it is possible that developed meltwater networks transport water from an ice shelf into the ocean. In this way, they prevent this destabilization. A better understanding of the development of meltwater features on an ice shelf is needed to make predictions on future ice shelf stability. This research investigates the development of meltwater features during one melting season on the Nivlisen ice shelf. The investigation consists of three elements. First, satellite imagery is used to analyse the change of meltwater area and volume. Next, a potential routing network is created to study the influence of topography on the shape of meltwater features. Finally, climate data is compared to the calculated volumes of the meltwater features. This study shows that it is possible to create a routing network that predicts the shape of meltwater features very well. It is essential that surface depressions are correctly incorporated in the flow routing algorithm. The currently available climate data underestimates the meltwater production significantly. The growth of observed meltwater features during the melting season is not reflected in the modelled melt data. To further study the development of meltwater features, the representation of hydrological processes in climate models has to be improved.