Dr. Salini-Calderon, Giovanni

We present here a study about the possible spread of covid-19 pandemic between human’s beings through aerosols contained in urban air polluted by respirable particulate matter and tropospheric ozone, as well as the incidence of local meteorology in an area with orographic basin characteristics and in a certain period of time. Hourly time-series data of three meteorological variables—temperature, relative humidity, wind speed—and three pollutants—PM10, PM2.5 and O3—were considered together with hourly data from the highest number accumulated sick's in seven communes—chosen at random—in Santiago, Chile, studying a probable link between them. From the epidemic perspective, the infected patients number was linked to the hourly time-series of meteorological and pollutant variables, generating new time-series. Nonlinear analysis and the chaos theory formalism was applied to these new time-series, obtaining the largest Lyapunov exponent, correlation dimension, Kolmogorov entropy, Hurst exponent and the Lempel-Ziv complexity. Our preliminary results show meteorological and air pollution variables can be part of the elements fraction that give sustainability to the accumulated growth of infected patients and favor the pandemic spread, making the accumulated sick’s curve chaotic and complex. In addition, environmental pollution could worsen disease conditions like coronavirus (COVID-19) infection. For all time-series, the Lempel-Ziv complexity turned out to be between 0 and 1 which is indicative of connectivity and chaos. The largest Lyapunov exponent as well as the Kolmogorov entropy were positive which also exhibits chaos. The Hurst exponent was found to be greater than 0.5 and less than 1 for all time-series, indicating positive long-term autocorrelation. Finally, the correlation dimension was less than 5, revealing that new time-series constructed are not random. © 2021, AAGR Aerosol and Air Quality Research. All rights reserved.

El objetivo de esta investigación es contrastar un modelo Gaussiano de dispersión de contaminantes, usando la rosa de los vientos de la ciudad de Andacollo (Chile), con un modelo cuya génesis está en la teoría del caos y que emplea datos crudos de carácter público de mediciones de la estación Andacollo del Sistema de Información Nacional de Calidad del Aire (SINCA) de Chile. Los datos conforman series de tiempo de material particulado, temperatura, humedad relativa, presión, radiación solar y magnitud de la velocidad del viento. El tratamiento caótico de cada serie entrega su exponente de Lyapunov, su coeficiente de Hurst y su entropía de correlación. La aproximación caótica muestra que las entropías de las variables meteorológicas actúan sobre la del contaminante provocando su decaimiento asintótico según perdida de persistencia, explicando sus interacciones térmicas localizadas. Se concluye que los modelos exhiben predicciones similares al comparar el decaimiento del contaminante PM10.