Impact of land use dynamics on land surface temperature: a multi-decadal analysis in Indian Sundarbans region

In order to ascertain the issue of rapid environmental changes, this paper attempts to analyse the dynamics of land use patterns and their inter-relationship with land surface temperature in the Indian Sundarbans region using multi-temporal satellite imageries covering 34 years (1990–2024) of time period. The changes are shown in five time periods such as 1990, 2000, 2010, 2020, and 2024. Supervised classifier algorithm is used for image classification while single-window algorithm and spectral radiance model are applied for extracting land surface temperature (LST). Additionally, several indices are also prepared along with classified images to show the specific changes. Significant alterations are found in respective intervals, while 1990–2000 interval indicates larger degradation in dense forest, second one (2000–2010) highlights major progress in built-ups, and third one (2010–2020) reveals maximum improve in aquaculture. Overall (1990–2024), areas under dense vegetation, and fallows are found to be decreased, whereas areas under sparse vegetation, built-ups, aquaculture, agricultural land, waterbodies, and mud floods are seen to be increased. In supporting this change, normalized differential vegetation index (NDVI) shows a decreasing trend while it has increased for both (NDWI) normalized differential water index and (NDBI) normalized differential built-up index from 1990 to 2024. Such alterations seem to have increased the mean surface temperature. Maximum LST is obtained from built-up area, followed by agricultural land, open forests, and aquacultural land. Hence, the study concludes that rapid alterations in land use patterns have serious implications for the local climate in Indian Sundarbans.