“…Because of its importance as an air pollutant, surface concentrations of NO 2 have been measured routinely throughout the world to monitor compliance with environmental regulations. These in situ measurements of NO 2 surface concentrations relate most directly to ambient exposures and have therefore informed many studies documenting the correlation between NO 2 concentrations in the atmosphere with human morbidity and mortality (Abdolahnejad et al., 2018; Brønnum‐Hansen et al., 2018; He et al., 2020; J. H. Lin et al., 2015; Linares et al., 2018; Orellano et al., 2020; Samoli et al., 2006; Tao et al., 2012; Williams et al., 2014; Zúñiga et al., 2016). Because of the sparsity of long‐term surface‐based monitoring networks throughout much of the world, satellite observations of the atmospheric column abundance of NO 2 have also proved extremely valuable in assessing global and regional changes in NO 2 (Abdelsattar et al., 2021; Barkley et al., 2017; Bauwens et al., 2020; Duncan et al., 2013; Goldberg et al., 2021; Gu et al., 2017; Huang & Sun, 2020; Jeong & Hong, 2021; Lorente et al., 2019; Mashat et al., 2016; Miyazaki et al., 2012; Mostafa et al., 2021; Ngo et al., 2021; Russell et al., 2012; Schaap et al., 2013; Vinken et al., 2014; C. Wang et al., 2020; L. Zhang et al., 2017).…”