National and Intraurban Air Pollution Exposure Disparity Estimates in the United States: Impact of Data-Aggregation Spatial Scale

Abstract

Air pollution exposure disparities by race/ethnicity and socioeconomic status have been analyzed using data aggregated at various spatial scales. Our research question is this: To what extent does the spatial scale of data aggregation impact the estimated exposure disparities? We compared disparities calculated using data spatially aggregated at five administrative scales (state, county, census tract, census block group, census block) in the contiguous United States in 2010. Specifically, for each of the five spatial scales, we calculated national and intraurban disparities in exposure to fine particles (PM 2.5 ) and nitrogen dioxide (NO 2 ) by race/ethnicity and socioeconomic characteristics using census demographic data and an empirical statistical air pollution model aggregated at that scale. We found, for both pollutants, that national disparity estimates based on state and county scale data often substantially underestimated those estimated using tract and finer scales; in contrast, national disparity estimates were generally consistent using tract, block group, and block scale data. Similarly, intraurban disparity estimates based on tract and finer scale data were generally well correlated for both pollutants across urban areas, although in some cases intraurban disparity estimates were substantially different, with tract scale data more frequently leading to underestimates of disparities compared to finer scale analyses.

Impacts of wind power on air quality, premature mortality, and exposure disparities in the United States

“…InMAP estimates at the census tract level are virtually identical to results from the same model aggregated at county scale, suggesting that the spatial resolution of air quality modeling and demographic information has little effect on estimated distributional impacts. This is consistent with a recent work showing that the exposure disparities among racial/ethnic groups are primarily driven by the regional (not local) variability in air quality (24) and the robustness of exposure disparity calculations at the census tract level compared with finer scale analyses (52). We observe similar variability and heterogeneity of wind power impacts on racial/ethnic minority and low-income populations across states between GEOS-Chem and InMAP (see fig.…”

Spatial Decomposition of Air Pollution Concentrations Highlights Historical Causes for Current Exposure Disparities in the United States

“…Findings from environmental justice (EJ) research documents higher-than-average exposures and attributable health risks for communities of color in the United States (US). − Studies on the underlying causes of environmental disparities − point to longstanding systems of racism, oppression, and unequal power, reflecting actions by individuals, companies, and government (more detailed literature review in the SI − ). Current explanations generally focus on neighborhood- and urban-scale inequalities, rather than the nature and causes of national-scale disparities.…”

Simulation of Neighborhood-Scale Air Quality with two-way coupled WRF-CMAQ over Southern Lake Michigan-Chicago Region

“…Observing platforms that do have better spatial coverage, e.g., remote sensed satellite observations, often have temporal limitations such as making only one observation a day in the case of polar orbiters (Goldberg et al, 2021). Given the need to resolve pollutants across impact-relevant scales (Clark et al, 2022), researchers often turn to physics-and chemistrybased Chemical Transport Models (CTMs) which allow for the spatial heterogeneity of pollutants to be estimated at high temporal resolutions in areas that are otherwise unmonitored (Hu et al, 2019;Southerland et al, 2021).…”