Biological and Environmental Research - Earth and Environmental System Sciences
Earth and Environmental System Modeling
19 September 2020

Using SciDAC Ice Sheet Models to Bound Antarctica’s Potential Contribution to Future Sea-Level Rise

Ice sheet models from DOE SciDAC’s ProSPect project have contributed to a multi-model intercomparison on the importance of ice shelf buttressing to Antarctica ice sheet evolution and sea level rise.

Science

Ice sheet models from DOE SciDAC’s ProSPect project have contributed to a multi-model intercomparison on the importance of ice-shelf buttressing to Antarctica ice sheet evolution. Results provide an upper bound estimate for potential sea-level rise from Antarctica ice sheet dynamics.

Impact

DOE’s contributions represent the highest-resolution, highest fidelity, and largest-scale computational simulations contributed. Multiple models applied to identical experiments provide an estimate for the impacts of model structural uncertainty on sea-level projections from ice sheet models.

Summary

Antarctica’s ice shelves modulate the flow of ice to the oceans and thus the rate of sea-level rise. Weakening of ice shelves due to climate forcing will decrease their ‘buttressing’ effect. While the processes governing ice-shelf weakening are complex, uncertainties in the response of the ice sheet are also difficult to assess. The Antarctic BUttressing Model Intercomparison Project (ABUMIP) compares ice-sheet model responses to a decrease in ice shelf buttressing by investigating the ‘end-member’ scenario of total and sustained loss of ice shelves. While unrealistic, this scenario enables estimating the sensitivity of a 15-member ice sheet model ensemble to a total and sustained loss of ice-shelf buttressing. All models predict that this scenario leads to multiple meters (1–12) of sea-level rise over 500 years, starting from the present day. West Antarctic ice sheet collapse alone leads to a 1.91–5.08 m sea-level rise. Improvements to marine ice-sheet models have greatly reduced variability between modeled ice-sheet responses to extreme ice-shelf loss.

Contact
Stephen Price
Los Alamos National Laboratory
Publications
Sun, S, F Pattyn, E Simon, T Albrecht, S Cornford, R Calov, C Dumas, et al.  2020.  "Antarctic ice sheet response to sudden and sustained ice-shelf collapse (ABUMIP)."  Journal of Glaciology 1-14.  https://doi.org/10.1017/jog.2020.67.