Modeling Antarctic Ice Sheet Dynamics in Response to Solar Radiation Management

The Antarctic Ice Sheet (AIS) could become the largest single contributor to future sea level rise (SLR). However, its response to rising global mean temperature remains highly uncertain, and potential Solar Radiation Modification (SRM) interventions during the 21st century further complicate the projections. Among these interventions, Stratospheric Aerosol Injections (SAI) have been proposed to limit atmospheric warming and potentially moderate or prevent AIS’ impact on SLR. This study examines the dynamic response of Antarctica to such SAI interventions, in the short-term (until the year 2100) and on centennial time scales. We use the Parallel Ice Sheet Model (PISM) forced by the Community Earth System Model 2 (CESM2) to compare the evolution of AIS under SAI scenarios with that under the Shared Socioeconomic Pathway 2-4.5 (SSP2-4.5). Our findings indicate that, on centennial timescales, SAI may be counterproductive in mitigating sea level rise due to the reduced Antarctic surface mass balance compared to the SSP2-4.5 scenario. Ice shelf thinning and grounding line dynamics emerge as dominant factors driving mid- and long-term AIS behavior, where ice dynamics dominate over the effects of constant climate forcing. Variations in the sliding law parameterization further influence simulated outcomes. Unsurprisingly, the results are highly dependent on the individual earth system model employed. To address this, we compare our findings with a suite of the Ice Sheet Model Intercomparison Project for CMIP6 (ISMIP6) scenarios, as well as additional SRM simulations performed using the Hadley Centre Global Environment Model version 2 (HadGEM2-ES).