Effect of Land Use/Land Cover Changes on Land Surface Temperature and Human Thermal Comfort in Greater Karu Urban Area of Nasarawa State, Nigeria

This study ascertain the effect of land use/land cover Changes on Land Surface Temperature and Human Thermal Comfort in Greater Karu Urban Area of Nigeria. Multi-criteria research design was used to acquire, process and analyse remotely sensed satellite imageries and other related dataset. The remote data used were Landsat TM, Landsat ETM and Landsat OLI that contain Land Surface Temperature data emitted by objects in the study area and stored the information as a digital number (DN). LANDSAT TM images were obtained for 4 different epochs; 1992, 2002, 2012 and 2022. The study used ESRI ArcGIS 10.8, ArcGIS Pro version 3.1.3 and Qgis version 3.22.5 for data acquisition, processing, modelling and analysis. Findings shows that water bodies, cropland and largely vegetal cover area are loss to built-up and bare surface in the GKUA. Findings shows that during the dry season area with low LST (< 200C) and area with moderate LST (>20–23) declining trend, area with high LST (>23-260C) and area with extreme LST (>260C) had increasing trend. During the dry season, area with low LST (< 200C) and area with moderate LST (>20–23) depict declining trend while are with high LST (>23-260C), area with high LST (>23-260C) and area with extreme LST (>260C) had an increasing trend. Substantially during the dry season, there was an increase in DI between 1992-2002 and 2012-2022 in areas with majority of the population anticipated to feel discomfort, area with the entire population feeling thermal discomfort and area with emergency thermal discomfort conditions increased in GKUA. During the wet season thermal DI between1992-2002 was more in areas where majority of the population are anticipated to have thermal discomfort in GKUA whilebetween 2002-2012 and 2012-2022 majority of the population were anticipated to feel discomfort, area with the entire population feeling thermal discomfort and area with emergency thermal discomfort conditions increased in GKUA. This study recommend urban greening of GKUA.

Keywords: LST, Discomfort, Index, Trend, Change, Detection.