Program on the Environment

Historical redlining contributed to systematic disinvestment of certain neighborhoods which continues to shape environmental health disparities today. Such disparities include reduced greenspace, higher temperatures, and poorer air quality, thus disproportionately burdening historically marginalized communities. The purpose of my project with the Nature Conservancy (TNC) was to examine how these inequities persist in the Tacoma Mall neighborhood, located about 35 miles south of Seattle. And to communicate these findings in an accessible way for both policymakers and local communities via an ArcGIS Story map. To address this, I conducted a literature review of 15 academic sources on redlining, environmental health disparities, and urban greening (tree planting) benefits. I also used ArcGIS to develop spatial maps incorporating temperature and PM2.5 air quality data from local TNC sensors, as well as landcover and tree canopy datasets from NOAA and the City of Tacoma. These methods allowed for empirical analysis, quantitative analysis, and visual communication of environmental health disparities. My results indicate that higher tree canopy coverage is associated with reduced temperatures and improved air quality at both 250-foot and 50-foot buffer boundary scales. These findings demonstrate that urban greening can have meaningful environmental health benefits at both neighborhood and highly localized scales. This work highlights the importance of greening initiatives as a climate resiliency and environmental justice strategy. By visualizing these disparities, this project supports more informed, equitable policy decisions and emphasizes the need for targeted investment in historically underserved communities.