Stronger Arctic amplification from ozone-depleting substances than from carbon dioxide

• Published in: Environmental Research Letters
• Main Authors: Yu-Chiao Liang, Lorenzo M Polvani, Michael Previdi, Karen L Smith, Mark R England, Gabriel Chiodo
• Format: Article in Journal/Newspaper
• Language: English
• Published: IOP Publishing 2022
• Subjects: ozone depleting substance; carbon dioxide; Arctic amplification; Environmental technology. Sanitary engineering; TD1-1066; Environmental sciences; GE1-350; Science; Q; Physics; QC1-999; Arctic; albedo; Sea ice
• Online Access: https://doi.org/10.1088/1748-9326/ac4a31; https://doaj.org/article/b920499c59d0441cb8ff08f771c1542a

Arctic amplification (AA)—the greater warming of the Arctic near-surface temperature relative to its global mean value—is a prominent feature of the climate response to increasing greenhouse gases. Recent work has revealed the importance of ozone-depleting substances (ODS) in contributing to Arctic warming and sea-ice loss. Here, using ensembles of climate model integrations, we expand on that work and directly contrast Arctic warming from ODS to that from carbon dioxide (CO _2 ), over the 1955–2005 period when ODS loading peaked. We find that the Arctic warming and sea-ice loss from ODS are slightly more than half (52%–59%) those from CO _2 . We further show that the strength of AA for ODS is 1.44 times larger than that for CO _2 , and that this mainly stems from more positive Planck, albedo, lapse-rate, and cloud feedbacks. Our results suggest that AA would be considerably stronger than presently observed had the Montreal Protocol not been signed.