Climate intervention on a high-emissions pathway could delay but not prevent West Antarctic Ice Sheet demise

Abstract

Solar radiation modification (SRM) is increasingly discussed as a tool to reduce or avert global warming and concomitantly the risk of ice-sheet collapse, as is considered possible for the West Antarctic Ice Sheet (WAIS). Here we analyse the impact of stratospheric aerosol injections on the centennial-to-millennial Antarctic sea-level contribution using an ice-sheet model. We find that mid-twenty-first-century large-scale SRM could delay but ultimately not prevent WAIS collapse in a high-emissions scenario. On intermediate-emissions pathways, SRM could be an effective tool to delay or even prevent an instability of WAIS if deployed by mid-century. However, SRM interventions may be associated with substantial risks, commitments and unintended side effects; therefore, emissions reductions to prevent WAIS collapse seem to be the more practical and sensible approach at the current stage.