DETECTION OF URBAN EXPANTION AND ITS IMPACT ON LAND SURFACE TEMPERATURE USING GIS AND REMOTE SENSING: THE CASE OF HAWASSA CITY ADMINISTRATION AND ITS SURROUNDING RURAL KEBELES

ABSTRACT Assessment of urban expansion and its impacts on land-use/land-cover change and investigating its relationship with land surface temperatures is very important to the study of human environmental interaction and urban climate change. The main objective of this study was detecting the impacts of urban expansion on land-use land-cover change and assessing its effect on land surface temperature using GIS and remote sensing. To analyze the LULC change of the study area, high and medium resolution satellite images were used such as spot for year 2007 and 2014, and Sentinel for year 2021 image. To extract land surface temperature, Landsat 7and 8 images were used. The method used in this study was supervised image classification technique with maximum likelihood algorithm for LULC mapping and spectral radiance model was applied to extract land surface temperature. Zonal statistical function was applied to analyze the relationship between LULC change and LST. This study result revealed that, the spatial distribution pattern of built-up and farmland shows increasing continuously from 2007-2021 whereas vegetation, open space and water body/wetland showed continuous decreasing. This study also affirmed that the distribution of the mean land surface temperature change was high in open space (28.82, 26.21 and 38.27) and built-up (27.66, 26.79 and 36.73) while in water body/wetland (22.18, 24.79 and 32.63) and vegetation (25.69, 25.12 and 35.89) for the study years 2007, 2014 and 2021 respectively. According to the result of this study, it can be concluded that urban expansion has direct relation with land-use/land-cover change and causes indirect impact on land surface temperature change. Therefore, reviewing our immediate urban LULC type transformation from one LULC type to another is very important for sustainable environmental management.