Footprints of COVID-19 on Pollution in Southern Spain

Abstract

Background: Many annual deaths in Spain could be avoided if pollution levels were reduced. Every year, several municipalities in the Community of Andalusia, located in southern Spain, exceed the acceptable levels of atmospheric pollution. In this sense, the evolution of primary air pollutants during the March–June 2020 lockdown can be taken as reliable evidence to analyze the effectiveness of potential air quality regulations. Data and Method: Using a multivariate linear regression model, this paper assesses the levels of NO2, O3, and PM10 in Andalusia within the 2017–2020 period, relating these representative indices of air quality with lockdown stages during the pandemic and considering control variables such as climatology, weekends, or the intrusion of Saharan dust. To reveal patterns at a local level between geographic zones, a spatial analysis was performed. Results: The results show that the COVID-19 lockdown had a heterogeneous effect on the analyzed pollutants within Andalusia’s geographical regions. In general terms, NO2 and PM10 concentrations decreased in the main metropolitan areas and the industrial districts of Huelva and the Strait of Gibraltar. At the same time, O3 levels rose in high-temperature regions of Cordoba and Malaga. Antecedentes: muchas muertes anuales en España podrían evitarse si se redujeran los niveles de contaminación. Cada año, varios municipios de la Comunidad de Andalucía, situada en el sur de España, superan los niveles aceptables de contaminación atmosférica. En este sentido, la evolución de los contaminantes atmosféricos primarios durante el confinamiento de marzo a junio de 2020 puede tomarse como evidencia confiable para analizar la efectividad de las posibles regulaciones de calidad del aire. Datos y Método: Mediante un modelo de regresión lineal multivariante, este trabajo evalúa los niveles de NO2, O3 y PM10 en Andalucía en el período 2017-2020, relacionando estos índices representativos de la calidad del aire con las etapas de confinamiento durante la pandemia y considerando variables de control como como la climatología, los fines de semana o la intrusión del polvo sahariano. Para revelar patrones a nivel local entre zonas geográficas, se realizó un análisis espacial. Resultados: Los resultados muestran que el confinamiento por la COVID-19 tuvo un efecto heterogéneo sobre los contaminantes analizados dentro de las regiones geográficas de Andalucía. En términos generales, las concentraciones de NO2 y PM10 disminuyeron en las principales áreas metropolitanas y los distritos industriales de Huelva y el Estrecho de Gibraltar. Al mismo tiempo, los niveles de O3 aumentaron en las regiones de alta temperatura de Córdoba y Málaga.Background: Many annual deaths in Spain could be avoided if pollution levels were reduced. Every year, several municipalities in the Community of Andalusia, located in southern Spain, exceed the acceptable levels of atmospheric pollution. In this sense, the evolution of primary air pollutants during the March–June 2020 lockdown can be taken as reliable evidence to analyze the effectiveness of potential air quality regulations. Data and Method: Using a multivariate linear regression model, this paper assesses the levels of NO2, O3, and PM10 in Andalusia within the 2017–2020 period, relating these representative indices of air quality with lockdown stages during the pandemic and considering control variables such as climatology, weekends, or the intrusion of Saharan dust. To reveal patterns at a local level between geographic zones, a spatial analysis was performed. Results: The results show that the COVID-19 lockdown had a heterogeneous effect on the analyzed pollutants within Andalusia’s geographical regions. In general terms, NO2 and PM10 concentrations decreased in the main metropolitan areas and the industrial districts of Huelva and the Strait of Gibraltar. At the same time, O3 levels rose in high-temperature regions of Cordoba and Malaga.