Landscape Transitions and Spatial Evolution of Surface Urban Heat Island in Abuja City, Nigeria: A Multitemporal Geospatial Analysis

Rapid urban expansion alters land-surface processes by replacing vegetated and agricultural landscapes with impervious built-up materials, thereby modifying surface energy exchange, vegetation condition, and urban thermal comfort. This study assessed long-term landscape transitions, vegetation spatial configuration, and surface thermal processes in Abuja City, Nigeria, from 1990 to 2020. Multi-temporal Landsat imagery was processed in Google Earth Engine to classify land cover and retrieve land surface temperature (LST). Land cover transitions were quantified, while vegetation condition and greenspace structure were evaluated using vegetation indices and landscape metrics describing greenspace proportion, patch size, shape complexity, fragmentation, connectivity, and isolation. Spatial clustering and the influence of vegetation configuration on LST were examined using Moran’s I, Pearson correlation, Ordinary Least Squares regression, and Spatial Lag Regression. Results show substantial land cover transformation, with built-up land increasing from 15.9% to 55.5% between 1990 and 2020, while vegetation and agricultural land declined. Mean LST increased from 31.23 °C in 1990 to 33.24 °C in 2020, representing a net rise of 2.01 °C. Built-up, bare, and agricultural surfaces recorded higher thermal signatures, whereas vegetation and water bodies maintained lower temperatures. Larger and more connected green space patches were associated with reduced LST, while fragmented, irregular, and isolated vegetation patches corresponded with higher temperatures. These findings demonstrate that urban heat mitigation in Abuja depends not only on retaining vegetation cover, but also on improving vegetation condition, increasing patch size, and maintaining spatially connected green spaces. The study provides geospatial evidence for climate-sensitive urban planning, green infrastructure design, and sustainable urban environmental process management in rapidly urbanizing African cities.