Geoengineering's role in reducing future Antarctic mass loss is unclear

Using the BISICLES ice sheet model, we compare the Antarctic ice sheets response over the 22nd century in a scenario where idealised large scale, instantaneous geoengineering is implemented in 2100 or 2050 (geoengineering), with scenarios where the climate forcing is held constant in the same year (stabilisation). Results are highly climate model dependent, with larger differences between models than between geoengineering and stabilisation scenarios, but show that geoengineering cannot prevent significant losses from Antarctica over the next two centuries. If implemented in 2050, sea level contributions under geoengineering are lower than under stabilisation scenarios. If implemented in 2100, under high emissions, geoengineering produces higher sea level than stabilisation scenarios, as increased surface mass balance in the warmer stabilisation scenarios offsets some of the dynamic losses. Despite this, dynamic losses appear to accelerate and may eventually negate this initial offset, indicating that beyond 2200, geoengineering could eventually be more effective.