Assessment of the surface urban heat island in Ho Chi Minh City using remote sensing and geographic information systems

The rapid urbanization of Ho Chi Minh City (HCMC) has led to an increasingly intense urban heat island (UHI) phenomenon, significantly impacting its environment and inhabitants. This study investigates the spatiotemporal dynamics of the surface UHI (SUHI) in HCMC by utilizing a 36-year time series of Landsat satellite imagery (1988, 1995, 2002, 2010, 2017, and 2024), processed within a geographic information system framework. Land surface temperature (LST) was derived to map and quantify UHI patterns. The results reveal a substantial and progressive intensification of the SUHI effect, with the citywide mean LST increasing from 25.4°C in 1988 to 28.7°C in 2024. Spatially, the SUHI has expanded from the urban core into peripheral suburban zones, particularly toward the east and northwest. A strong and consistent negative correlation (R2 > 0.7) was observed between LST and the normalized difference vegetation index, underscoring the critical role of green spaces in mitigating urban heat. These findings provide crucial, data-driven insights for urban planners and policymakers, highlighting the urgent need for sustainable development strategies—such as enhancing green infrastructure and adopting cool materials—to combat the adverse effects of urban warming in this rapidly expanding tropical metropolis.