Ananya Roy, Syeda Tasnim Nowshin, Marufa Jahan Tonni, Md Habibur Rahman Habib and Mst. Tanjina Akter
DOI: https://doi.org/10.55706/jae1915
Abstract
Rapid unplanned urbanization, particularly in developing countries, significantly alters land surface characteristics and microclimatic conditions through LULC changes that increase urban surface temperatures, damage vegetation and water bodies, and contribute to ecosystem degradation, climate change, and accelerated global warming. This study evaluates the spatiotemporal relationships among changes in LULC, surface temperature, and the DI in Mymensingh District, Bangladesh. Satellite images were analyzed for the years 2004, 2015, and 2025, along with meteorological data, using GIS and RS techniques. The results show that the proportion of natural bodies is decreasing because of rapid expansion of built-up areas, resulting a sharp rise in surface temperature and higher DI values. The LULC classification achieved satisfactory accuracy, with overall accuracy ranging from 86–90% and Kappa coefficients between 0.82–0.87. From 2004 to 2025, built-up areas increased by approximately 78%, while vegetation cover and water bodies decreased by 10.54% and 82.28%, correspondingly. The year 2015 represented a transitional phase of urban expansion, during which increased vegetation cover contributed to a decrease in average LST from 25.47°C (2004) to 22.73°C. However, by 2025, rapid urbanization increased the average LST to 24.08°C. Discomfort Index analysis revealed that the region was thermally comfortable in 2004, whereas moderate discomfort zones emerged in 2015 and intensified by 2025, when over 53% of the population is projected to experience moderate discomfort and 4.23% extreme discomfort. Rising thermal stress may increase heat-related illnesses, dehydration, cardiovascular risks, sleep disturbances, mental stress, and economic burdens, with children, elderly people, and vulnerable individuals being the most affected.
Keywords: Land Use Land Cover (LULC); Land Surface Temperature (LST); Discomfort Index (DI); Urbanization; Thermal Discomfort.
