| Summary: | Abstract--During a study of marine aerosol characteristics ata coastal site on South Uist in the Outer Hebrides, early in August 1986, an extended period with untypically low wind speeds (below 7 m s-1) was experienced. Over this period, lasting several days, very low particle concentrations were measured for all observed particle radii from 0.09 to 23.5/~m, and atmospheric visibilities of up to 80 km were noted. Particles larger than about 0.2 #m in radius howed a decline in concentration throughout this episode, suggesting that these data could yield information on particle loss rates, as well as providing a true very low wind speed background aerosol distribution for this region of the North Atlantic. Analysis of these data indicates that the decay of aerosol concentration, for all particle radii greater than 0.25 gm, may be approximated by an exponential function, and is consistent with a simple model of turbulent dry deposition of the aerosol to the ocean surface. Key word index: Marine aerosol, size spectra, dry deposition.
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