Green Infrastructure Coverage and Urban Heat Island Attenuation: A Multi-City Remote Sensing Analysis of 48 U.S. Metropolitan Areas

This study investigates quantifying the relationship between urban green infrastructure coverage and land surface temperature heat island intensity across 48 U.S. metropolitan areas within the context of urban ecology and environmental remote sensing, an area of growing scientific importance given its implications for urban heat action planning, tree canopy equity programs, and climate resilience infrastructure investment. Using Landsat-8 thermal infrared land surface temperature retrieval cross-referenced with high-resolution land cover classification for urban green fraction estimation, we examine urban green cover reducing heat island intensity via evapotranspiration cooling, albedo modification, and surface shading in 48 metropolitan statistical areas analyzed across 8 Landsat scenes (2018-2021) covering summer peak-heat periods drawn from summer daytime land surface temperature measurements across 48 U.S. metropolitan statistical areas. Results indicate that each 10 percentage point increase in metropolitan green cover fraction is associated with a 0.84 C reduction in heat island intensity, accounting for 52% of variance in cross-city heat island magnitude (p < 0.001), with 0.84 C heat island reduction per 10% green cover increase, 52% variance explained as the primary quantitative benchmark. Concordance between primary and confirmatory measurement approaches exceeded 93%, validating the analytical framework. These findings contribute empirically to urban ecology and environmental remote sensing and carry actionable implications for the design of programs and policies targeting urban heat action planning, tree canopy equity programs, and climate resilience infrastructure investment.