Dynamic trends in land surface temperature and land use/land cover transitions in semi-arid metropolitan city, Jaipur.

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The increasing surface heat in metropolitan areas is one of the biggest issues, especially as natural surfaces are being replaced by impermeable concrete surfaces. This study uses Landsat data (1991-2022) to examine the spatio-temporal dynamics of LST and LULC in Jaipur, highlighting the impact of urban expansion and the city's semi-arid nature on the thermal landscape. We have used the maximum likelihood classifier for supervised LULC classification and the mono-window algorithm for retrieving LST. The evaluation is done using buffer analysis. Furthermore, to assess the interrelationship between LST and LULC indices (NDVI & NDBI), regression analysis is used. The CA-ANN model is employed to project LSTs of 2032 and 2042. The findings indicate that the built-up land in the study area grew by 52.80% from 1991-2022. Most of this expansion has come at the expense of agriculture/open land, and vegetation cover. The mean LST in the city has risen by 5.9°C, with the inner zone (B1) increasing from 35.44°C to 41.93°C, indicating urbanisation-induced heat stress. In the outer zones (B5-B6), dry sandy and rocky soils contribute to elevated temperatures. Water bodies show the lowest LST, while open and barren lands have the highest. LST exhibit a positive correlation with NDBI and a weak negative correlation with NDVI. Predictions indicate that by 2042, about 99% of the urban landscape will encounter surface temperatures above 40°C, with 28.79% exceeding 45°C. Raised temperatures could exacerbate the UHI effect, leading to serious health and environmental concerns.