Wet deposition in shallow convection over the Southern Ocean

Abstract

Southern Ocean (SO) air is amongst the most pristine on Earth, particularly during winter. Historically, there has been a focus on biogenic sources as an explanation for the seasonal cycle in cloud condensation nuclei concentrations (NCCN). NCCN is also sensitive to the strength of sink terms, although the magnitude of this term varies considerably. Wet deposition, a process encompassing coalescence scavenging (drizzle formation), is one such process that may be especially relevant over the SO. Using a boundary layer cloud climatology, NCCN and precipitation observations from Kennaook/Cape Grim Observatory (CGO), we find a statistically significant difference in NCCN between when the upwind ..