Urban sprawl impact assessment on the land surface temperature over the green capital of Gujarat using a geo-spatial approach

Abstract

In developing countries, examining land use land cover (LULC) change pattern is crucial to understand the land surface temperature (LST) effect as urban development lacks coherent policy planning. The variability in LST is often determined by continuously changing LULC pattern. In this study LULC change effect analysis on LST has been carried out using geometric and radiometric corrected thermal bands of multi-spectral Landsat 7 ETM + and 8 TIRS/OLI satellite imagery over Gandhinagar, Gujarat in the years 2001 and 2022 respectively. Maximum likelihood classification (MLC) was applied to assess LULC change while NDVI-based single channel algorithm was used to retrieve LST using google earth engine (GEE). Results showed a substantial change in built-up (+ 347.08%), barren land (-50.74%) and vegetation (-31.66%). With change in LULC and impervious surfaces, the mean LST has increased by 5.47 ℃. The impact of sparse built-up was seen on vegetation and agriculture as maximum temperature of > 47℃ was noticed in all LULC classes except agriculture where the temperature reached as high as > 49℃ in 2022. Since Gandhinagar is developing on a twin-city (Gandhinagar-Ahmedabad) plan this study could be used as scientific basis for sustainable urban planning to overcome dynamic LULC change impacts.