“New Normal”: The Dynamics of Air Pollutants on the Interruption–Recovery Pattern Related to the COVID-19 Pandemic in Recife, Northeastern Brazil

Abstract

Recife, located in Northeastern Brazil, was one of the first cities in the country to suffer the devastating effects of the COVID-19 Pandemic. The strict measures adopted in the first months of the pandemic seem to have had results and the city had a second wave less intense than other Brazilian capitals. This condition allowed a series of measures to make human activities more flexible until September 2021. In this context, the aim of the study was to evaluate the behavior of Air Pollutants between the months of May 2020 and September 2021, observing the timeline of Interruption-Recovery of economic activities. The concentrations of pollutants (O 3 , NO 2 , SO 2 , PM 2.5 , PM 10 and CO) were obtained by satellite, as well as meteorological variables, used to predict the levels of pollutants in the year 2021 using machine learning. The comparison of monthly averages of pollutants between 2020 and 2021 showed a significant increase in NO 2 , SO 2 , PM 2.5 , PM 10 and CO, in addition to a decrease in O 3 concentrations. Estimated data for the year 2021 from machine learning showed that the levels of NO 2 , SO 2 , PM 2.5 , PM 10 and CO were higher than expected at 15.9%, 14.6%, 25.9%, 15.3% and 2.2%, respectively, while O 3 levels were 6.7% lower than expected. The results show the return of pollutant levels (except O 3 ) to higher levels compared to those measured in the months of greater restriction of human mobility, a behavior similar to that found in other parts of the world.

Weekend effect of air pollutants in small and medium-sized cities: The role of policies stringency to COVID-19 containment

“…However, the similarity in behavior of meteorological parameters between the two periods analyzed, as detailed in the supplementary material ( Tables 2S, 3S and 4S ), allows for a degree of certainty that the differences observed may be attributed to the level of restrictions imposed to curb the spread of COVID-19. This hypothesis is supported by previous studies that have identified similar patterns of response to air pollutants during different phases of the pandemic (e.g., interruption and recovery of normal activities) when comparing data with and without taking meteorological parameters into account, as demonstrated by da Silva Júnior (2022) .…”

“…If an annual assessment were performed, they would probably also observe increases after the pandemic, but with more expressive intensities. In a Brazilian study investigating the interruption–recovery pattern related to the COVID-19 pandemic in Recife, showed an increase in levels of air pollutants (with the exception of O 3 ) in the scenario considered as “new normal” ( da Silva Júnior 2022 ).…”

“…The levels of all assessed atmospheric pollutants (O 3 , NO 2, SO 2, PM 2.5 and PM 10 ) were obtained from satellite data of the Copernicus Atmospheric Monitoring Service (CAMS) from the European Centre for Medium-Range Weather Forecasts (ECMWF) and manually obtained in real time from The Weather Channel application (IBM, USA). The procedure was performed according to Da Silva Júnior et al (2020) and other studies ( Carvalho et al, 2022 ; da Silva Júnior, 2022 ; Tavella et al, 2022b ). To ensure data quality control, all extractions were performed at regular intervals and by trained personnel.…”