Assessment of urban heat island using geospatial techniques: a case of vagamon hill Station, Kerala

This study investigates the formation of Urban Heat Island (UHI) of Vagamon, a hill station, Kerala, India, with a focus on winter months (December and January). While UHI is typically studied during summer, this study examines its presence and characteristics in cooler months of winter season. Utilizing satellite imagery from 2013 and 2024, the study employs Land Surface Temperature (LST), Normalized Difference Built-Up Index (NDBI), and Normalized Difference Vegetation Index (NDVI) for analysis. The findings reveal the presence of UHI in Vagamon during winter. Four specific UHI spots exhibit high LST and high NDBI, indicating a correlation between built-up structures and high surface temperatures. Temporal analysis from 2013 to 2024 suggests an increase in UHI intensity, with the spatial extent when low UHI values decreases in Vagamon. This highlights the potential expansion of UHI further in Vagamon. Notably, despite the area's rich ecosystem and high elevation, UHI formation persists even during winter. The study concludes that non-climatic factors like land-use change (LULC), urbanization, and human activities contribute to UHI development in Vagamon, even within its winter months. The increasing UHI intensity necessitates mitigation strategies to reduce surface temperature and safeguard the ecological balance of this unique hill station.