Current and Future Arctic Aerosols and Ozone FromRemote Emissions and Emerging Local Sources-Modeled Source Contributions and Radiative Effects

摘要

The Arctic is influenced by air pollution transported from lower latitudes, and increasingly by local sources such as shipping and resource extraction. Local Arctic emissions could increase significantly in the future due to industrialization in a warming Arctic and further influence Arctic climate. We use the regional model Weather Research and Forecasting, including chemistry, to investigate current (2012) and future (2050) sources of Arctic aerosol and ozone pollution and their radiative impacts, focusing on spring and summer emissions from midlatitude anthropogenic sources, biomass burning, Arctic shipping, and Arctic gas flaring. Results show that remote anthropogenic and biomass burning emissions are likely to remain the main source of Arctic pollution burdens and of black carbon (BC) deposition over snow, and the main contributors to direct aerosol and ozone radiative effects in the Arctic. However, local Arctic flaring emissions are already a major source of BC in northwestern Russia, with a direct radiative effect of ~25 mW/m~2, and Arctic shipping is a strong current source of aerosols and ozone during summer in the Nordic Seas. We find that the direct effect of ozone and aerosols from summertime Arctic shipping is respectively negative (due to frequent temperature inversions) and positive (because of the high surface albedo) in our simulations, two new results. With the development of diversion shipping through the Arctic Ocean in summer 2050, Arctic shipping emissions could become the main source of surface aerosol and ozone pollution at the surface, with strong associated indirect effects of -0.8 W/m2, while flaring would remain an important BC source.