Field Measurements of Aerosol Production from Whitecaps in the Open Ocean

Simultaneous measurements of near-surface aerosol and bubble spectra were made during 6 buoy deployments in the open ocean during two cruises in the North Atlantic as part of the SEASAW project, a UK contribution to the international SOLAS program. The measurements were used to estimate the sea-spray aerosol production from a unit area of whitecap for each deployment. Estimates of the mean sea spray flux were then made by scaling the whitecap production fluxes with photographically derived in-situ estimates of whitecap fraction. The mean bubble number concentrations for each deployment were also measured; they were found to be in broad agreement with other open ocean spectra, and one to two orders of magnitude lower than bubble spectra from a previous laboratory study and measurements from a surf zone.