23 January, 2018

Climate impacts from a removal of anthropogenic aerosol emissions

Authors

Samset BH, Sand M, Smith CJ, Bauer SE, Forster PM, Fuglestvedt, J. S., Osprey, S., Schleussner, C.-F

Limiting global warming to 1.5 or 2.0°C requires strong mitigation of anthropogenic greenhouse gas (GHG) emissions. Concurrently, emissions of anthropogenic aerosols will decline, due to coemission with GHG, and measures to improve air quality. However, the combined climate effect of GHG and aerosol emissions over the industrial era is poorly constrained. This study shows the climate impacts from removing present-day anthropogenic aerosol emissions and compares them to the impacts from moderate GHG-dominated global warming.

Key messages

Aerosol emission removal can warm the climate by more than 0.5°C
Key climate variables are more sensitive to aerosol removal than to GHG increase
Regional impacts of 1.5°C warming depend on the balance between aerosol and GHG forcing

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Decarbonisation targets and 1.5℃ pathways

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