Utilización de información satelital para estimar la calidad del aire a nivel de superficie : Evaluación de los datos satelitales de material particulado en contraste con la información de superficie de la Red Metropolitana de Monitoreo Atmosférico de Quito.

Abstract

In this study, the quality control and statistical processing of the database of the Metropolitan Atmospheric Monitoring Network of Quito (REMMAQ) are presented, as well as the processing of satellite information from the MODIS and Sentinel 2 satellites for the estimation of particulate matter less than 2.5 microns (PM2.5) based on aerosol optical thickness (AOT). These two types of information are contrasted to determine the feasibility of using satellite information as an optimal alternative for air quality monitoring at the local and national levels. The results indicate that the MODIS satellite provides more reliable and feasible raw data for modeling and estimating PM2.5 from AOT, as the correlation coefficients of the polynomial regressions range from 0.79 to 0.96, suggesting a strong and intimate relationship between these two variables. On the other hand, results with the Sentinel 2 sensor indicate that more exhaustive image processing is required. Additionally, air quality estimated from satellite images, both at the local and national levels, has resulted in an overestimation or underestimation of PM2.5 concentration in the study area. This may be due to various factors related to the quantity, quality, level of processing, characteristics, and structure of the satellite image, such as excessive cloud cover or illumination, the presence of specialized layers in atmospheric variables, absence of data in the area and period of study, among others.