Urban Heat Island Disparities: A Geospatial Analysis of Household Income and Land Surface Temperatures in Lafayette, Louisiana

Abstract

The urban heat island (UHI) effect increases heat exposure in cities and disproportionately affects vulnerable groups. This study investigates the relationship between household income, vegetation cover, and land surface temperature (LST) in Lafayette, Louisiana. We used Landsat 8 thermal infrared imagery from July 30, 2023, to measure LST at a 30-m resolution. We then compared these results with 2018 U.S. Census block group income data.  We classified land cover into vegetation and non-vegetation classes using 2023 NAIP aerial images, and we validated our classification with an accuracy assessment based on 200 random points. Our results show a negative relationship (r = −0.38, R² = 0.14, p < 0.05) between income and surface temperature and a positive relationship (r = 0.41, R² = 0.17, p < 0.05) between income and vegetation. Block groups with lower incomes also had less vegetation cover. This suggests that the lack of vegetation contributes to higher LST. We did not find a significant relationship between parcel size and income, which means that land ownership density alone does not explain differences in heat.  These findings highlight how socioeconomic and environmental factors work together to create uneven heat burdens. Policymakers may consider targeted tree planting and green infrastructure projects in vulnerable communities to mitigate heat-related risks and reduce energy costs.