November 19, 2021
Journal Article

Aerosol Responses to Precipitation Along North American Air Trajectories Arriving at Bermuda

Abstract

North American pollution outflow is ubiquitous over the western North Atlantic Ocean, especially in winter, making this location an ideal natural laboratory for investigating the impact of precipitation along air mass trajectories during pollution long-range transport. We take advantage of observational data collected at Bermuda to seasonally assess the sensitivity of aerosol mass concentrations and volume size distributions to accumulated precipitation at the surface along trajectories (APT). The mass concentration of particulate matter with aerodynamic diameter less than 2.5 µm normalized by the enhancement of carbon monoxide above background at Bermuda (PM2.5/?CO) was used to estimate the degree of aerosol loss during transport to Bermuda. Results for December-February (DJF) show most trajectories come from North America and have the highest APTs, which results in the most significant reductions (by 53%) in PM2.5/?CO under high APT conditions (> 13.5 mm) relative to low APT conditions (

Published: November 19, 2021

Citation

Dadashazar H., M. Alipanah, M. Hilario, E. Crosbie, S. Kirschler, H. Liu, and R. Moore, et al. 2021. Aerosol Responses to Precipitation Along North American Air Trajectories Arriving at Bermuda. Atmospheric Chemistry and Physics 21, no. 21:16121-16141. PNNL-SA-162998. doi:10.5194/acp-21-16121-2021