Urban Expansion and its Influence on Land Surface Temperature: A Case Study of Patna City, India

Abstract

Rapid urbanization in developing countries has significant implications for local climate and environmental conditions. This study examines land use/land cover (LULC) changes and their impact on land surface temperature (LST) in Patna, India from 1988 to 2022 using Landsat imagery and geospatial techniques. Rapid urbanization in developing cities can significantly alter local climate, but the dynamics in Patna were not well understood. Using supervised classification and thermal band analysis, the research quantified LULC transformations and LST changes over 34 years. Results show dramatic urban expansion, with built-up area increasing from 38 % to 80 % of the total area, while vegetation cover decreased from 44 % to just 7 %. These changes corresponded with an overall increase in LST, with maximum temperatures rising by 1.06°C and minimum temperatures by 6°C. Strong correlations were found between LST and spectral indices like NDVI (negative) and NDBI (positive). The study reveals accelerated urban growth and temperature increases, especially after 2005, highlighting the need for sustainable urban planning strategies to mitigate heat island effects and improve thermal comfort in Patna. This research provides valuable baseline data for understanding urbanization impacts on local climate in rapidly growing Indian cities.