Reduced ice loss from Greenland under stratospheric aerosol injection

J. C. Moore, R. Greve, C. Yue, T. Zwinger, F. Gillet-Chaulet and L. Zhao


Sea level rise due to dynamic losses from the ice sheets – that is via accelerated flow of glaciers into the sea, is something that may be potentially mitigated by cooling the ice sheet and oceans via solar geoengineering. We use two ice dynamic models driven by changes in surface mass balance to estimate the sea level rise contribution from the Greenland ice sheet under the IPCC Representative Concentration Pathway (RCP) 4.5, and 8.5 and GeoMIP (Geoengineering Model Intercomparison Project) G4 scenarios. The G4 scenario adds 5 Tg/yr sulfate aerosols to the equatorial lower stratosphere (equivalent of 1/4 the 1991 Mt Pinatubo SO2 emission rate) to the IPCC RCP4.5 scenario which itself approximates to the Nationally Determined Contribution (NDC) greenhouse gas emission commitments agreed in Paris in 2015. Over the 2020–2090 period mass loss under G4 is about 38% that under RCP4.5. Ice lost across the grounding line under both G4 and RCP4.5 is reduced in future as the termini of many southeast Greenland outlets retreat onto higher bedrock. Glaciers with large low-lying catchments in the west, north and northeast of Greenland (e.g. Jakobshavn, 79N, Zachariae Isstrøm, and Petermann glaciers), drain more ice from the ice-sheet interior under RCP4.5 than under G4.

Journal of Geophysical Research: Earth Surface (submitted).

Last modified: 2023-01-05