Development of multi-scale indices of human mobility restriction during the COVID-19 based on air quality from local and global NO2 concentration

Larissa Haringer Martins da Silveira; Marcio Cataldi; William Cossich Marcial de Farias

doi:10.1016/j.isci.2023.107599

Development of multi-scale indices of human mobility restriction during the COVID-19 based on air quality from local and global NO₂ concentration

iScience. 2023 Aug 11;26(9):107599. doi: 10.1016/j.isci.2023.107599. eCollection 2023 Sep 15.

Authors

Larissa Haringer Martins da Silveira¹, Marcio Cataldi^{1

2}, William Cossich Marcial de Farias³

Affiliations

¹ LAMMOC Group, Department of Agricultural and Environmental Engineering, Biosystems Engineering Graduate Program, Universidade Federal Fluminense, Niterói 24210-240, Brazil.
² MAR Group, Department of Physics. School of Chemistry. University of Murcia, 30100 Murcia, Spain.
³ National Electric System Operator, Rio de Janeiro 20211-160, Brazil.

Abstract

This study investigated whether variability in air quality, especially related to vehicular emissions, during the COVID-19 pandemic could indicate social distancing. Data from in situ measurements and satellite estimates were used. The study areas were São Paulo, Brazil, and Bologna, Italy. We focused our analysis on NO₂, a combustion-derived pollutant, because of its availability in surface stations and satellite tracking, and because it has a short atmospheric lifetime. The analyses included graphical, statistical, and wavelet transform-based approaches to understand NO₂ concentrations before and during the pandemic. After confirming the reduction in vehicular emissions during the pandemic, we created normalized indices to assess the social remoteness in 2020 in different locations, with a focus on São Paulo and Bologna. These indices were compared to existing indices based on cell phone mobility. The indices proposed in this study suffered high sensitivity to social distance compared to existing ones and helped to understand the actual application of social distance and contamination rates, considering the various dimensions of the problem.

Keywords: Atmospheric science; Health sciences; Remote sensing.