Concentrations of particulate mercury in the Atlantic marine atmosphere

The concentrations of mercury have been determined in atmospheric particulates collected by a shipboard filter method from locations over the North and South Atlantic Ocean. In the North Atlantic westerlies at 57°N the geometric mean mercury concentration was 0.035 ng (SCM)^?1, whilst at middle and low latitude the mean was 0.011 ng (SCM)^?1. A geometric mean concentration of 0.007 ng (SCM)^?1 was observed in the South Atlantic. The interhemispheric differences in concentration were interpreted as reflecting variations in the anthropogenic contribution to the marine aerosol. The results were used to estimate the flux of mercury to Atlantic surface waters. An upper limit for the flux of mercury from the atmosphere to the North Atlantic was calculated to be between 600-380 t yr^?1 and 150-100 t yr^?1 for the South Atlantic.