Population pressure, infrastructural development, and economic growth are the reasons for increasing urbanization process although urban expansion. Land-use change, vegetation degradation, and also climate change are the results of urban heat island (UHI). Land surface temperature (LST) is an essential aspect of global climate change studies, calculating radiation budgets, heat balance studies, and also estimating the climate change scenario. In this study, investigate the UHI using thermal remote-sensing data. Satellite thermal data are used to calculate the thermal variation in Kolkata metropolitan and surrounding area. The remote-sensing technique is used to detect land use in 2020 using supervised classification, calculation of LST, and variation of mean LST from this region. The maximum and minimum temperatures are 33 °C and 18 °C individually. This study analyzes the LST distribution correlation with different spectral indicator. The relationship between NDVI and SAVI results shows negative correlation (R² 0.20 and 0.15, respectively) because of vegetation area effect on urban expansion. The urban heat island shows positive relation between LST and NDBI and UI because of urbanization and industrial development. The R² values are show 0.61 and 0.27, respectively. The relationship between MNDWI and NDBal is showing 0.0003 and 0.04 individually. Kolkata metropolitan and surrounding urban areas are increased temperature due to urbanization, climate change and global warming and overuse of public vehicles. The UHI was increased due to anthropological activities. This study helps to identify the recent thermal variation of this area and build a proper management and planning for sustainable urban development.

尽管城市扩张，人口压力、基础设施发展和经济增长是城市化进程不断加快的原因。土地利用变化、植被退化以及气候变化都是城市热岛 (UHI) 的结果。地表温度 (LST) 是全球气候变化研究、计算辐射收支、热平衡研究以及估计气候变化情景的重要方面。在本研究中，使用热遥感数据调查 UHI。卫星热数据用于计算加尔各答大都市及周边地区的热变化。遥感技术用于使用监督分类、LST 计算和该地区平均 LST 的变化来检测 2020 年的土地利用。最高和最低温度分别为 33 °C 和 18 °C。本研究分析了LST分布与不同光谱指标的相关性。NDVI与SAVI结果呈负相关（R² 0.20 和 0.15），因为植被面积对城市扩张的影响。由于城市化和工业发展，城市热岛在 LST 与 NDBI 和 UI 之间显示出正相关关系。R ²值分别显示为 0.61 和 0.27。MNDWI 和 NDBal 之间的关系分别显示为 0.0003 和 0.04。由于城市化、气候变化和全球变暖以及公共交通工具的过度使用，加尔各答大都市和周边城市地区的气温升高。由于人类学活动，UHI 增加。这项研究有助于确定该地区最近的热变化，并为可持续城市发展建立适当的管理和规划。