Systematic modeling of impacts of land-use and land-cover changes on land surface temperature in Adama Zuria District, Ethiopia

Land surface temperature (LST) has been increasing year after year globally. The present investigation was aimed to study the impact of land-use/land-cover changes on LST in the Adama Zuria District in Ethiopia. Land-use/land-cover, LST and Normalized Difference Vegetation Index were extracted from Landsat TM (1989), Landsat ETM + (1999) and Landsat 8 OLI/TIRS (2016) using GIS and remote sensing tools. Land surface temperature was assessed using split window algorithm. Land-use/land-cover changes that occurred during 1989-2016 in the study area were evaluated and analyzed using geospatial tools and verified by field data. Results indicated that farmland covered more than 60% during the study period (1989-2016) followed by shrub land (>12%). Most areas with lower LST in 1989 were changed to higher LST in 1999 and 2016 in response to different changes in land-use/land-cover pattern. By linking land-use/land-cover pattern changes and LST using zonal statistics, LST is found to have negative relationship with the extent of vegetation cover. Land surface temperature results showed that the northwestern, south, lake Koka area and along Awash river relatively low LST that ranged between 9 and 21 degrees C in response to the high NDVI values. The eastern, Adama town and western part of the study area showed high LST of up to 42 degrees C. Visual comparison of 1989, 1999 and 2016 images showed that the land-use/land-cover type and NDVI status play a major role for the variability of LST values. Correlation between LST and land-use changes has indicated that changes to settlement/urban land-use/land-cover have influenced LST proportionately. Relevant measures are to be taken by the bodies concerned to minimize land-use/land-cover changes to gain effective control over increasing LST in the study area.