Monitoring land use dynamics, urban sprawl, and land surface temperature in Dimapur urban area, Nagaland, India

The study's primary objective is to measure the rate and pattern of land use and land cover changes in Dimapur city, as well as their impact on land surface temperature (LST). Landsat TM (Thematic mapper) data from 2000 and 2007, as well as Landsat OLI (Operational land imager) and TIR (Thermal infrared sensor) data from 2020, were used in the study. In order to examine the city's population patterns, the study was supplemented using LandScan global gridded data for the pre-defined years (1KM x 1KM). The urban sprawl index (USI) was employed to detect urban sprawl in Dimapur, while the urban thermal field variant index (UTFVI) was utilized to investigate surface urban heat islands. Dimapur's built environment grew from 14.74 percent to 39.36 percent between 2000 and 2020, while green spaces shrank from 33.21 percent to 19.44 percent. Between 2000 and 2007, the USI value increased from 0.0037 to 0.0055, indicating substantial urban sprawl in recent years. Between 2000 and 2020, these changes resulted in an increase in mean LST of 17.27 degrees C (winter) and 26.86 degrees C (summer) to 19.01 degrees C (winter) and 31.43 degrees C (summer). According to UTFVI, the number of locations classified as ecologically bad or worse in Dimapur has increased in recent years. The larger positive correlation between population and built-up areas and LST, as well as the stronger negative correlation between vegetation and population and LST, support the impact of population-induced land use and land cover change on LST development in Dimapur urban area.