Impact of Urbanization on Temperature Trend Using Geospatial Techniques in Ondo State, Nigeria

摘要

Abstract The conversion of natural/vegetated surfaces into residential, commercial, and industrial areas has contributed to increased land surface temperature (LST). The knowledge of surface temperature is essential to a range of issues and themes in earth sciences central to urban climatology, global environmental change, and human-environmental interactions. This paper aims to establish the impact of urbanization on land surface temperature. Hence, remote sensing and GIS techniques were applied to Landsat data to examine the land use for three (3) periods within thirty-two (32) years (1984–2016). Also, the LST was obtained by converting the thermal band to a surface temperature map, while the relationship between land use and temperature emission was established using zonal statistical analyses. The result showed a rapid urbanization footprint at the expense of vegetation and forest land use categories. Furthermore, the land surface temperature increased rapidly over the period of study with a noticeable spatio-temporal variation that is modified by land-use features. The built-up area has the highest LST, which justifies the steady temperature increase over time due to urban expansion. Also, rock outcrop contributes to UHI because of their thermal conductivity. While water bodies, forests, and vegetation regulate the surface temperature of their immediate surrounding. The level of development of each local government area affects its average temperature, thus confirming the presence of UHI. Finally, the result highlighted rock outcrop, built-up, and fallow land as a significant driver of high urban heat intensity value.