A fast and simplified subglacial hydrological model for the Antarctic Ice Sheet and outlet glaciers
Year: 2024
Type: article
Abstract: . We present a novel and computationally efficient subglacial hydrological model that represents in a unified way both hard and soft bed rheologies as well as a dynamic switch between efficient and inefficient subglacial discharge. The subglacial model is dynamically linked to a regularized Coulomb friction law, allowing for a coupled evolution of the ice sheet on decadal to centennial time scales. The hydrological model is tested on an idealized marine ice sheet and subsequently applied to the drainage basin of Thwaites Glacier, West Antarctica, that is composed of a heterogeneous (hard/soft) bed. We find that subglacial hydrology embedded in the sliding law accelerates the grounding line retreat of Thwaites Glacier under present-day climatic conditions. Highest retreat rates are obtained for hard bed configurations and/or inefficient drainage systems. We show that the sensitivity is particularly driven by large gradients in effective pressure, more so than the value of effective pressure itself in the vicinity of the grounding line. Clearly, a better understanding of the subglacial system is needed with respect to both the spatial and temporal variability in effective pressure and bed rheological conditions.
Source: The cryosphere
Institutions: Université Libre de Bruxelles, University of Liège
Language: English
Subfield: Atmospheric Science
Field: Earth and Planetary Sciences
Domain: Physical Sciences
SDG: Climate action
Open Access status: gold
Estimated APC paid: $1,574
OpenAlex ID: W4405416965