LAND ARTIFICIALIZATION AND INTENSIFICATION OF URBAN HEAT ISLANDS IN ABIDJAN, CÔTE D’IVOIRE: A SPATIOTEMPORAL ANALYSIS FROM 2002 TO 2024

According to the Intergovernmental Panel on Climate Change (IPCC), changes in land cover could increase air temperature in urbanized areas by up to 4 °C by 2100. Urban heat islands are a major concern because of their effects on human health and economic activities. In Côte d’Ivoire, Abidjan is experiencing increasing frequency and intensity of heatwaves. However, the influence of spatiotemporal land use and land cover dynamics on UHI remains poorly documented. This study analyzes land use and land cover dynamics and their influence on UHI in Abidjan between 2002, 2014, and 2024. Landsat and MODIS AQUA data were used to map land cover and land surface temperature. The NDVI and NDBI indices were used to assess the influence of vegetation and built-up areas on UHIs. Relationships were analyzed using Pearson correlation and geographically weighted regression (GWR). Results show a 19.60 % increase in built-up areas and an 18.57 % decrease in vegetated areas. Mean UHI-related temperature increased from 30.22 °C to 31.88 °C, representing a rise of 1.66 °C. NDBI showed positive correlations with UHIs (0.65 in 2002, 0.74 in 2014, and 0.75 in 2024), while NDVI showed negative correlations (-0.63, -0.62, and -0.49, respectively). GWR results indicate spatial variations in these relationships, with predominantly positive NDBI coefficients and negative NDVI coefficients. These findings highlight the association between urbanization, vegetation loss, and UHI intensification in Abidjan, emphasizing the need to preserve vegetation and control urban expansion.