Temporal Analysis of Land Surface Temperature for Urban Heat Island Detection in Thimphu, Bhutan

Abstract

Climate change is a matter of considerable global importance, as evidenced by the increased urban surface temperatures in developed and undeveloped areas. Hence, this study aims to analyze the threshold and index of the urban heat island (UHI) phenomenon within the urban region of Thimphu, Bhutan. This study conducts a temporal analysis of the Normalized Difference Vegetation Index (NDVI), Normalized Different Buildup Index (NDBI) and Land Surface Temperature (LST) to detect Urban Heat Islands (UHIs) in Thimphu, Bhutan. The research focuses on assessing changes in vegetation cover and surface temperatures over time to identify and understand the patterns of UHI development in urban areas. This has potential benefits for urban planners involved in urban planning and management, as well as for increasing public awareness regarding the urban heat island effect. Advancements in thermal remote sensing, GIS, and statistical techniques have facilitated the monitoring of LST and its association with Land Use and Land Cover (LULC). To investigate this connection, supervised classification, and change detection were conducted to ascertain the spatial trends in LULC changes. Subsequently, the spatial distribution of LST was acquired using the thermal band of Landsat imagery. Regression analysis was then applied to investigate the link between surface temperature and various land surface characteristics, including both types of land use and land cover, as well as associated indices. In summary, this analysis contributes to the broader understanding of urbanization impacts on the local climate and provides valuable insights for sustainable urban planning and climate mitigation strategies in Thimphu, Bhutan.