Aerosol-driven North Pacific High anomaly enhances sea ice loss in the Chukchi Sea

Abstract

The Arctic has warmed significantly faster than the rest of the globe, leading to rapid sea ice decline. Anthropogenic aerosols are traditionally viewed as cooling agents that do not contribute to Arctic sea ice loss. Here we investigate how aerosol-induced changes in atmospheric circulation patterns contribute to Arctic sea ice decline using a fully-coupled global earth system model. We compared single forcing experiments to examine individual and combined effects of greenhouse gases and anthropogenic aerosols. Aerosols contribute to intensification of the North Pacific anticyclone, which enhances heat transport into the Arctic through the Bering Strait. When combined with greenhouse gas-induced warming, aerosols have a greater impact on Arctic sea ice decline in the western Chukchi Sea compared to when either forcing acts independently. This compound effect challenges the traditional view of aerosols as solely cooling agents, demonstrating that anthropogenic aerosols can accelerate Arctic sea ice melting.