DUST CONCENTRATION IN THE PATAGONIAN SHELF (ARGENTINA).

AUGUSTO CÉSAR CRESPI ABRIL; DE CIAN, ANTONELLA; SORIA, GASPAR; GONÇALVES, RODRIGO; BARBIERI, ELENA; PAPARAZZO, FLAVIO

Bari

Congreso; III International Conference on Atmospheric Dust; 2018

Patagonia is the major source of aeolian dust into the southern part of the Atlantic Ocean and Argentineanshelf. However, few measurements of dust concentration were conducted over the ocean in these regions. Theobjective of this study is to analyze the spatial distribution of dust concentration over the Argentineancontinental shelf on the northern Patagonia (43ºS-48ºS). Dust concentration was measured on 74 stations on anoceanographic survey conducted on board of the O/V Puerto Deseado between October 28 and November 8 of2017. Measurements were conducted with a particle counter (PCE-PCO 1) and the concentration (number ofparticles per liter of air: p/l) was estimated in six classes of particle sizes: 0.3um, 0.5um, 1.0um, 2.5um, 5.0umand 10um. Additionally, complementary data of relative humidity and air temperature were measured. Particleconcentrations varied inversely of particles sizes: the highest concentration was observed for smaller particlesand 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 spatialdistribution, 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 and45ºS. Based on these results, the southern part contributed with more dust particles to the Argentinean shelfthan the northern part.