Land Surface Temperature Variation in Response to Land Use Modes Changes: The Case of Mefou River Sub-Basin (Southern Cameroon)

Abstract

Land surface temperature (LST) estimation at the river sub-basin level is crucial for developing land use planning at the basin scale and beyond. The main goal of this study was to analyze LST variations in response to land use mode (LUM) changes in the Mefou River sub-basin (Southern Cameroon) using geospatial techniques. To achieve this goal, we used Landsat 7 Enhanced Thematic Mapper Plus (2000 and 2010) and Landsat 8 Operational Land Imager (OLI)/Thermal Infrared Sensor (TIRS) data for 2020. We also used air surface temperature data from the Climatic Research Unit (CRU) to validate the LST. Our results reveal that between 2000 and 2020, the Mefou watershed recorded significant changes in LUMs, which were mainly manifested by an increase in impervious areas (IAs) (buildings and roads (+10%); bare soils and farmlands (+204.9%)) and forest reduction (−31.2). This decrease in the forest was also reflected by a reduction in NDVI values, the maximum of which went from 0.47 in 2000 to 0.39 in 2020. Contrary to the forest area and the NDVI values, the LSTs of the investigated basin increased over the period studied. There is a strong negative correlation between LST and NDVI. In general, high LSTs correspond to low NDVI values. For the years 2000, 2010 and 2020, the links between these two variables are materialized by respective correlation coefficients of −0.66, −0.74 and −0.85. This study could contribute to understanding the impact of LUM changes on the local climate, and could further provide assistance to policymakers in regard to land use planning and climate change mitigation strategies.