Dynamics of the Urban Heat Island in Lagos Metropolis, Nigeria (1984 to 2013)
Urban Heat Islands (UHI) occur when
cities record higher temperatures than surrounding rural areas due to land
cover modification and anthropogenic heat. In Lagos metropolis, rapid
urbanization has altered land use and land cover, but spatiotemporal UHI
dynamics over three decades remain poorly quantified. This study analyzed UHI
dynamics in Lagos metropolis from 1984 to 2013 using remote sensing data from
Landsat-5 TM, Landsat-7 ETM+, and Landsat-8 OLI/TIRS imagery. Land surface
temperature (LST) was retrieved from thermal bands, and urban-rural extents
were delineated through supervised classification in GIS. UHI zones were
identified using mean LST thresholds for each time period. Urban built-up area
expanded while rural open land declined, intensifying UHI. Urban LST increased
from 24.76°C in 1984 to 28.59°C in 2013, and UHI extent grew from 125.01 km² to
319.38 km², a 155.4% increase. Findings confirm that land use/land cover change
driven by urbanization is the primary driver of UHI intensification in Lagos.
Mitigation should prioritize increasing urban vegetation and high-albedo
roofing. Street canyon design to enhance wind circulation is critical along the
Ifako/Ijaye, Oshodi/Isolo, and Lagos Island corridor.