Ecological Appraisal of Urban Heat Island in Zaria, Nigeria
Keywords:
Urban Heat Island (UHI), Land Surface Temperature (LST), Urban Thermal Field Variance Index (UTFVI), Landsat OLI/TIRS/ETM , Normalized Difference Vegetation Index (NDVI)Abstract
With rapid population growth, urbanization, coupled with other anthropogenic activities, Zaria, Nigeria experiences, UHI, with a steady increase in surface and atmospheric temperatures over the years. This study evaluates the UHI in the study area and its effect on the ecology, using Landsat ETM+ and OLI/TIRS remotely-sensed data, between 2009 and 2019. The satellite data were used to derive NDVI and LST for 2009, 2015 and 2019 while the UHI effects on the quality of urban life was evaluated using UTFVI. Results indicate that there is an increase of 2.44oC in the mean surface temperature in Zaria between 2015 and 2019, with a slight overall decrease of 1.88oC between 2009 and 2019. The hot spot of UTFVI were found mainly in the bare, uncultivated lands, built-up areas, especially the commercial and industrial districts. These areas are the most vulnerable to UHI phenomenon and negatively affected in ecological quality. In general, a large portion of the city experiences ecologically worse UHI effects, indicating a need for continued UHI mitigation efforts.
