Source Apportionment of Size Resolved Airborne Particulate Matter on Sable Island, Nova Scotia, Canada

Abstract

Marine biogenic VOC rapidly undergo gas-to-particle conversion, and can serve as a significant natural source of ultrafine airborne particulate matter, that can alter global climate. However, the role phytoplankton emissions play in UFP and cloud formation, and subsequent mediation of climate are still not well understood. In this study, the relationship between marine phytoplankton abundance and size-resolved particle number and mass was studied on Sable Island as part of the NASA NAAMES study. Utilizing the USEPA PMF source apportionment model yielded four size-resolved factors (sources of PM): sea spray (2.2% of total UFP), secondary marine biogenic particles (78.2%), long range transport (4.4%) and island surface dust (15.2%). The strong correlations between UFP (20-30 nm & 30-50 nm) and chlorophyll a (R2 = 0.815 and R2 = 0.815), was the most salient feature of this study and provides powerful insight into ocean-atmosphere dynamics that remain high uncertainty in global climate.