Impact of Urban Tree Canopy on Land Surface Temperature and Green Space Inequities in Suwon, South Korea

Urban trees provide benefits that reduce urban heat stress, but these benefits are often inequitably distributed.Most existing research relies on coarse-resolution data that fail to capture fine-scale spatial distributions of green space and the associated social inequalities.This study addresses that critical gap by investigating vegetation-heat dynamics and environmental equity in a dense urban environment.To achieve a high-resolution analysis, we examined Suwon, South Korea, by integrating a 0.25 m tree canopy map with 30 m Landsat 8-derived land surface temperature (LST), key socioeconomic indicators, and the local climate zone (LCZ) framework.We quantified the seasonal relationship between total green space (TGS) and LST, assessed fraction-dependent cooling effects, assessed green space per capita, and identified administrative districts where vegetation is scarce, heat exposure is extreme, and the elderly population is high.Our results revealed a significant, nonlinear cooling effect: the thermal benefits of tree canopy increase sharply up to approximately 40% coverage before diminishing.The key finding is the confirmation of severe spatial inequality of TGS.Dense urban cores, which have high concentrations of vulnerable elderly residents, frequently fall below the World Health Organization's 9 m greenspace per person standard.In contrast, peripheral neighborhoods retain extensive forest canopy, highlighting a systemic disparity in access to green infrastructure.This study provides one of the first fine-scale assessments of vegetationheat equity in a Korean city.By linking fraction-dependent cooling with spatial inequities, it demonstrates the need for targeted greening strategies that advance both climate adaptation and environmental justice.