Geospatial Analysis of the Impact of Land Cover Change on Land Surface Temperature in Abuja, Nigeria (1986-2021)

Abstract

Urbanization has significantly altered land cover patterns, leading to rising land surface temperatures (LST) and the intensification of the Urban Heat Island (UHI) effect. This study examines the impact of land cover change on LST in the Federal Capital Territory (FCT) - Abuja, Nigeria, from 1986 to 2021, using geospatial techniques. Landsat 5 TM, Landsat 7 ETM+, and Landsat 8 OLI imagery were analyzed to assess land cover changes, extract LST, and compute the Normalized Difference Vegetation Index (NDVI). Supervised classification was performed using ERDAS Imagine, and LST was derived through radiometric calibration, brightness temperature estimation, and regression analysis. Results indicate a substantial decline in vegetation cover from 52.7% in 1986 to 37.5% in 2021, alongside a significant increase in built-up areas from 3.15% to 16.8%. Correspondingly, LST values showed an upward trend, with mean surface temperatures rising from 27.4°C in 1986 to 33.2°C in 2021, highlighting the intensification of UHI effects. A strong inverse correlation (-0.76) between NDVI and LST suggests that vegetation loss contributes directly to rising surface temperatures. The study recommends enhanced urban planning policies focused on afforestation, green infrastructure, and Climate-responsive land use to mitigate urban heating effects and enhance sustainability.