SO2 and aerosol evolution over the very clear atmosphere at the Argentina Andes range sites of San Antonio de los Cobres and El Leoncito

PIACENTINI RUBEN; MICHELETTI MARÍA ISABEL; GARCÍA BEATRIZ; FREIRE MARTÍN MIGUEL; DELLA CECA LARA

Basel

Congreso; Second International Electronic Conference in Atmospheric Sciences; 2017

Multidisciplinary Digital Publishing Institute

Abstract: The atmosphere at North-Central Argentina Andes range is exceptionally clear for theplacement of astrophysical/astronomical/solar observatories (Piacentini et al, Advances SpaceResearch, 2016). However, this region is part of the Pacific fire belt, due to the large number of activevolcanoes. Consequently, the possibility of having strong sporadic emissions of different gases andaerosols needs to be investigated. In the present work, we analyze in particular the SO2 trace gas,since it can affect significantly the solar UVB (280-320 nm) radiation. Also, particulate matter canattenuate this radiation in the UV-visible ranges. One of the most significant contributions tovolcanic eruptions that could arrive at the selected San Antonio de los Cobres (SAC) location is thenear Lascar volcano. We used satellite images form the OMI/KMNI/Aura/NASA satelliteinstrument, for deriving the intensity of the eruption at the SAC geographical point. An importanteruption was that of the Puyehue/CordónCaulle volcanic complex at Chile Patagonia, in June 2011.No significant influence on the other selected El Leoncito (LEO) location was registered. We presentaerosol optical depth (AOD550) satellite data obtained with the Deep Blue Level 2 data providedby the SeaWiFS/SeaStar/NASA satellite instrument for SAC and LEO places, showing thatAOD550 for the whole period is extremely low (0.0262 for SAC and 0.0266 for LEO). We alsopresent ground atmospheric aerosol concentration measurements as a function of aerosol diameterwith a high quality GRIMM laser instrument for some days of campaing performed in those sites.