CONCENTRATIONS AND SIZE DISTRIBUTIONS OF AEROSOL-PARTICLES IN COASTALZONE

This paper presents the behaviour of aerosol size distributions and nu mber concentrations with respect to specific meteorological conditions , deduced from experiments conducted over a period of 3 yr, in the Med iterranean coastal zone.Specific meteorological conditions, ''East'' w ind and ''Mistral'' wind lead to specific size distributions and total number concentrations. In an ''East'' wind situation (steady winds, w eak sunniness, high humidity), the size distributions are characterize d by only accumulation and coarse particle modes. ''Mistral'' wind sit uations (gusty winds, strong sunniness, low humidity), lead to greater concentrations and the corresponding size distributions are often cha racterized by an Aitken peak but no accumulation peak. After a specifi c time-lag which depends on the particle size and meteorological condi tions, the concentrations of coarse particles are well correlated with the wind velocity. In case of high ''Mistral'' winds, particles in th e Aitken range and the wind velocity also are well correlated. It seem s likely that the wind, by bursting small bubbles at the sea-air inter face, is the major generation mechanism for these particles. Copyright (C) 1996 Elsevier Science Ltd