Assessment of spatio-temporal changes of land surface temperature (LST) in Kanchenjunga Biosphere Reserve (KBR), India using Landsat satellite image and single channel algorithm

Abstract

Land surface temperature (LST) is known as skin temperature of the earth surface and it is used for analyzing the energy balance and thermal flux of the earth surface. The rise of surface temperature is a major environmental concern at present day. The present study analyzed the spatio-temporal pattern and changes of LST in Kanchenjunga Biosphere reserve (KBR) of Sikkim Himalaya, India from 1994 to 2019. Single channel algorithm has been used to estimate the LST from Landsat 5, 7 and 8 satellite imageries. Correlation analysis was carried out to understand the correlation of LST with altitude, vegetation indices, snow index and water index. The result shows there is bilinear correlation between LST with altitude, vegetation indices (NDVI, PV and EVI), snow index (NDSI) and water index (NDWI). Vegetation indices positively correlated with LST whereas NDSI and NDWI negatively correlated with LST. To understand the spatial association of LST, Moran's spatial autocorrelation method has been used which reveals that there is strong positive spatial uniformity of LST. Local Moran's I index was used to detect spatio-temporal cluster pattern and outlier of LST from 1994 to 2019. Spatial mean method used to understand the spatio-temporal changes of LST in the study area. From this analysis, it is clear that there is significant spatio-temporal change of LST observed in the study area.