Analyzing Urban Heat Islands in Pokhara Metropolitan City-Nepal through Remote Sensing Techniques

Abstract

This study provides a comprehensive analysis of the temporal and spatial dynamics of Surface Urban Heat Islands (SUHI) in Pokhara Metropolitan City, Nepal, over the period from 2013 to 2022. Utilizing advanced satellite data and various indices to quantify Land Surface Temperature (LST) variations, this research uniquely focuses on a rapidly urbanizing region in the context of a developing country facing the consequences of climate change. The results reveal significant temperature disparities between urban and suburban areas, with urban zones exhibiting markedly higher maximum (39.13 °C), mean (33.23 °C), and minimum (28.48 °C) LST values compared to their suburban counterparts (34.43 °C, 29.49 °C, and 25.90 °C, respectively). Temporal assessments indicate a consistent increase in LST and an expansion of thermal hotspots, particularly during warmer months, underscoring the intensifying SUHI effect. Correlation analyses further elucidate a moderate negative relationship between the Normalized Difference Vegetation Index (NDVI) and LST (r = -0.58), highlighting the cooling influence of vegetation, while a strong positive correlation with the Normalized Difference Built-up Index (NDBI) (r = 0.82) emphasizes the impact of urbanization on rising temperatures. These findings underscore an urgent need for sustainable urban planning that integrates green spaces and adaptive design strategies to mitigate SUHI effects, reduce thermal stress on residents, and enhance urban resilience against climate change impacts, thereby advocating for increased vegetation cover, sustainable construction practices, and innovative cooling solutions to improve overall urban living conditions.