Spatial and Temporal relationship between NDVI and Land Surface Temperature of Faisalabad city from 2000-2015

Abstract

The study estimates the land surface temperature of Faisalabad city. For the current study Landsat ETM+ images of 2000, 2003, 2010 and OLI/TIRS 2015 were acquired from USGS of the study area. Normalized Difference Vegetation Index (NDVI) was developed and NDVI based classification was used to calculate the vegetation area. The digital number of thermal infrared band is converted into spectral radiance using the equation supplied by the Landsat user’s hand book. The effective at-sensor brightness temperature has been obtained from the spectral radiance using Plank’s inverse function. The surface emissivity based on NDVI is used to retrieve the final LST. The research aims to investigate the spatial and temporal pattern of vegetation and land surface temperature and also to determine the correlation between land surface temperature and Vegetation in study area from 2000 to 2015. The results reveal decrease in vegetation area results in increase in the LST. The vegetation area decreases from 34 to 14.3 percent with average increase in LST mean from 39.8 to 44 degree Celsius from 2000-2015. The research suggested that more studies should be conducted with images and sensors of higher resolution and seasonal variation can be assessed for the LST.