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This study considers the influence of both stratospheric and tropospheric aerosol changes on Arctic sea ice extent on interannual to decadal timescales. While it is well-known that accounting for volcanic aerosol increases the skill of interannual to decadal predictions of surface temperature, its impact on sea ice prediction has not been widely considered. Here we analyze the impact of historical volcanoes on Arctic sea ice extent using a large ensemble of 20th-century climate simulations, and demonstrate that an increase in Arctic sea ice extent following these eruptions persists for up to a decade. Even though we do not find a detectable response in observations, these results suggest that inclusion of the effect in seasonal to interannual predictions of sea ice extent should improve skill on these timescales. Secondly, while the influence of future greenhouse gas changes on sea ice extent is known to be important for predictions on decadal timescales, the influence of projected tropospheric aerosol changes has received less attention. We examine the simulated response of Arctic sea ice to projected aerosol and aerosol precursor emissions changes under the Representative Concentration Pathway (RCP) scenarios, and show that projected aerosol emissions decreases drive approximately 20-30% of the projected decrease in annual mean Arctic sea ice extent on decadal timescales.