The oceanic sensitivity of the Antarctic Ice Sheet

Resumen

Sea-level rise is one of the most serious consequences of climate change for humanity. The Antarctic Ice Sheet (AIS) is the largest ice sheet in the world and, therefore, potentially the largest contributor to future sea-level rise. In particular, the West Antarctic Ice Sheet (WAIS) contains the two largest ice shelves of the world, the Filchner-Ronne (FRIS) and the Ross ice shelf (RIS). These ice shelves are components of the climate system that are highly prone to suer an abrupt change. Their collapse would facilitate the acceleration of the inland ice streams feeding them, causing a sea-level rise of several meters. This process is forced by an oceanic warming and is considered likely for the following centuries. The aim of this work is to study the relevant forcing factors of the ice-ocean interactions and to constrain the future evolution of the AIS and specically the WAIS by assessing its sensitivity to and its interactions with the ocean. These are fundamental issues for the understanding of climate dynamics, and necessary for accurately projecting future sea-level rise. In order to achieve this, a three-dimensional ice sheet model capable of representing both the dynamics of grounded ice sheet and oating ice shelves is used. Here we present a new parametrization of the basal melt of the oating parts of Antarctica. Our results show that a massive retreat of the FRIS and RIS is possible, which could lead to a collapse of the whole WAIS.