Dust concentration in San Jorge Gulf and adjacent Patagonian Shelf (Argentina)

AUGUSTO C. CRESPI-ABRIL; RODRIGO J. GONÇALVES; ANTONELLA DE CIAN; ELENA S. BARBIERI; FLAVIO E. PAPARAZZO; GASPAR SORIA

Bari

Conferencia; III International Conference on Atmospheric Dust - DUST 2018; 2018

Italian Association for the Study of Clays (AISA - onlus) and Institute of Methodologies for Environmental Analysis (IMAA) - CNR

Patagonia is the major source of aeolian dust into the southern part of the Atlantic Ocean and Argentinean shelf. However, few measurements of dust concentration were conducted over the ocean in these regions. The objective of this study is to analyze the spatial distribution of dust concentration over the Argentinean continental shelf on the northern Patagonia (43oS-48oS). Dust concentration was measured on 74 stations on an oceanographic survey conducted on board of the O/V Puerto Deseado between October 28 and November 8 of 2017. Measurements were conducted with a particle counter (PCE-PCO 1) and the concentration (number of particles per liter of air: p/l) was estimated in six classes of particle sizes: 0.3um, 0.5um, 1.0um, 2.5um, 5.0um and 10um. Additionally, complementary data of relative humidity and air temperature were measured. Particle concentrations varied inversely of particles sizes: the highest concentration was observed for smaller particles and the lowest concentration was observed for higher particles (mean concentration for 0.3um: 18500 p/l; 0.5um: 7030 p/l; 1.0um: 1750 p/l; 2.5um: 390 p/l; 5.0um: 80 p/l; 10um: 44 p/l). Regarding the spatial distribution, the highest concentration of particles was measured in the southern part of the studied area,between 46oS and 48oS, while the lowest concentration was measured in the northern part between 43o30?S and 45oS. Based on these results, the southern part contributed with more dust particles to the Argentinean shelf than the northern part.