Impact of Urbanization on Land Use Land Cover and Urban Climate, using Spatio-temporal Techniques: A case study of Islamabad, Pakistan

An increase in urban population has been considered a major challenge over the past few years, especially in developing countries like Pakistan. It reduces vegetation area that directly affects land surface temperature (LST) and thus causes major changes in urban climate. This research mainly focuses on the surface temperature of Islamabad using LULC, LST, and Normalized Difference Vegetative Index (NDVI) as major parameters. This study spans over four years i.e., 2019, 2020, 2021, and 2022. The land use land cover maps are obtained from ESRI Sentinel 2 Land Use Land Cover Explorer. In contrast, LST maps are obtained from Level 2 Sentinel 2B Sea and Land Surface Temperature Radiometer (SLSTR) sensor LST product. NDVI is calculated using Sentinel 2B bands 4 and 8 respectively. The resulting LULC maps show that the vegetation area decreases by 7% and the built-up area increases by 8% from 2019 to 2022. Moreover, the area of dense vegetation decreased from 6.01% to 0.17% from 2019 to 2022 shown by NDVI maps. The study further reveals that the built-up areas exhibit higher LST than other classes. This is validated through Pearson’s Correlation Coefficient between LST and NDVI which shows a negative correlation of -0.41. This research concludes that the built-up area and rangeland are increasing during the studied years while the area of vegetation and bare ground is decreasing in Islamabad. This decrease directly influences LST and consequently the climate of the area. This should be mitigated by adopting such sustainable plans that involves building green alternatives into urban management.