Mineral and sea salt aerosol concentrations over low latitude tropical Atlantic and Pacific oceans During FGGE

Abstract

During the two periods of field observations of the First Garp Global Experiment (FGGE), from January to March and May to July, 1979, atmospheric aerosol samples were taken on board the Mexican R/V "Mariano Matamoros" and "DM 20", at two geographical points over the Pacific (7° N, 84° W) and Atlantic (7° 30'N, 42° 30'W) Oceans. The determined components were mineral and sea salt aerosol. On the Atlantic Ocean the geometric mean of the mineral aerosol was 7.27 μg/m3, and for the sea salts 2l.38: μg/m3. On the Pacific ocean, the concentration of these components was 0.62 and 6.28 μg/m3, respectively; these were the first extensive studies about mineral and sea salt aerosol in this region. A criterion of the minimization of the error given by x2 was used for the statistical analysis of mineral and sea salt concentrations. Bi-modal log-normal distributions were obtained for the Atlantic Ocean, and only simple log-normal distribution for the Pacific Ocean; these results show statistically the presence of two and one sets of physical phenomena related with the presence of aerosol. For the Atlantic Ocean, the concentrations reported in this work agree with those reported by other authors. For the Pacific Ocean, the values reported here are higher than those reported in the literature for other regions of this ocean.