Geospatial Analysis of LST and UHI Variability in Relation to Land Use/Land Cover Changes in Anambra State, Nigeria

Rapid urbanization and land use/land cover (LULC) changes have significantly altered land surface temperature (LST) patterns and intensified urban heat island (UHI) effects, particularly in rapidly developing regions of sub-Saharan Africa. This study aims to analyze the spatial variability of LST and UHI in relation to LULC changes across urban and rural areas of Anambra State, Nigeria. The study integrates Landsat 8 satellite imagery (2019 and 2024), Shuttle Radar Topography Mission (SRTM) Digital Elevation Model (DEM), and geospatial analysis techniques. We classified LULC using a Support Vector Machine (SVM) algorithm and derived LST from thermal infrared bands using the Multi-Window Algorithm (MWA) with NDVI-based emissivity correction. UHI intensity was estimated using statistical threshold methods based on mean LST and standard deviation. Results indicate a 15.1% expansion of built-up areas, particularly in urban centres such as Onitsha, Nnewi, and Awka, leading to LST values exceeding 35.68°C and UHI intensities up to 30.59°C. In contrast, rural areas such as Ayamelum, Ogbaru, and Anambra West exhibited lower temperatures (below 31.37°C), attributed to higher vegetation cover and proximity to water bodies. However, ongoing deforestation and agricultural expansion have contributed to moderate temperature increases in rural regions. The study concludes that LULC changes are a primary driver of thermal variability in Anambra State. Sustainable land-use planning, afforestation, and climate-responsive urban design are essential for mitigating UHI effects and enhancing environmental resilience.