Padrões atmosféricos associados com altos valores de espessura ótica sobre a América do Sul

Abstract

Aerosols are particles suspended in the atmosphere in the form of liquid or particles that, due to their influence on the formation of precipitation, atmospheric visibility and radiative balance, are the subject of studies on their presence and quantity in the atmosphere. This work aims to perform a synoptic analysis on the days with the highest values of Optical Aerosol Thickness (EOA) in the period from 2013 to 2018 in South America (SA) aiming at the existence of atmospheric patterns that may influence this increase. Applying the 99th percentile to the entire data series (0.955), the points with the highest EOA value (above P99) were separated, and among these points that showed similarities in the performance of some atmospheric systems, such as the UPC, were separated. GEAB Valledupar (Colombia), UNC Palmira, (Colombia), Quito USFQ (Ecuador) and Pilar Cordoba (Argentina). The increase in EOA was investigated using images of fire outbreaks through the INPE fire bank and the trajectory of these aerosols to the EOA point was traced 96 hours before the day of the maximum point value. Among the similarities found between the points selected for optical thickness analysis, the 4 had their maximum values during the performance of two meteorological systems operating simultaneously (Alta da Bolivia and VCAN), 3 of these points with peaks in the same month of the same year. When observing the first three points, a consecutive decrease in OAE values can be seen, which may mean that the aerosols from the second and third point were transported from the region of the first point and the Pilar Cordoba region shows no connection. with the other 3 points. No patterns were found in EOA behavior due to the different data period found for each AERONET measurement point. The only systems that were repeated, due to the months in which the high values of EOA were identified, were AB and VCAN, which were found acting at the same time at all points. It was also detected that JBNs can be major contributors to the transport of aerosol particles due to their detection and their position in the different days analyzed in this work.