VAST

We want to carry out an in-depth analysis of how the circum-antarctic thermocline depth depends on changes in wind speed and direction, putting their relation into functional form. Based on that, we aim to find critical wind-stress thresholds, indicating the regional potential of future warm-water intrusion into the different ice-shelf cavities around Antarctica. Further, we plan to implement this process of a wind-driven thermocline into a sophisticated, yet computationally efficient ice-sheet model. For the first time this will allow simulations of the flow dynamics of the entire AIS in response to basal ice-shelf melting that is sensitive to wind-driven thermocline changes. Conducting an ensemble of simulations, we plan to provide projections of the future Antarctic sea-level contribution, associated with projected regional changes in the atmosphere. In further sets of experiments, we intend to systematically vary the thermocline depth to conceptually explore the ice-sheet’s sensitivity to changes in larger-scale atmospheric variability, e.g., to changes in frequency, amplitude and trend of recurring El-Niño events. In a final step we envisage to generate an Antarctic risk map that indicates the regional impact of potential warm-water entrainment with respect to the long-term ice-flow response and ice-sheet stability.