Mapping Urban Heat Island Effects in Lagos Metropolis Using Surface Temperature Data

The urban heat island (UHI) phenomenon has become increasingly pronounced in rapidly expanding African megacities, with Lagos presenting a compelling case for meteorological investigation. This study maps UHI intensity across Lagos Metropolis by comparing land surface temperature (LST) differentials between densely built-up urban cores and surrounding peri-urban and rural fringes. Landsat-8 thermal infrared imagery acquired between 2020 and 2023 was processed using ERDAS Imagine and ArcGIS platforms to derive spatiotemporal LST distributions. Ground-truth temperature measurements from automated weather stations operated by NiMet supplemented the satellite-derived estimates. Results indicate that commercial districts such as Lagos Island and Ikeja record mean LST values between 4.5 and 7.2 degrees Celsius higher than vegetated outskirts, confirming a marked UHI signature. Land use/land cover analysis reveals a strong inverse relationship between green space coverage and surface temperature, with impervious surface expansion accounting for the primary driver of thermal anomalies. The study highlights the public health implications of elevated nocturnal temperatures, particularly for low-income communities residing in high-density neighborhoods with limited vegetation. Recommendations focus on urban greening initiatives, reflective roofing policies, and integration of thermal comfort considerations into Lagos State urban planning regulations. The findings provide accessible, evidence-based insights suitable for informing municipal climate adaptation strategies. Keywords: urban heat island, Lagos, land surface temperature, remote sensing, urban planning.