Assessment of spatiotemporal land use land cover changes and its impacts on land surface temperature in the Shigar district of Gilgit Baltistan, Pakistan

Land use land cover plays an essential role in altering regional micro and macro climate, diminishing biodiversity, and significantly influences Land Surface Temperature (LST). However, no research has been conducted in the Shigar district to investigate LULC changes, particularly the correlation between LST and vegetation/snow cover at higher elevated regions. Therefore, this study was carried out in the Shigar district of Gilgit Baltistan Region, Pakistan, due to its extreme climatic variability. In this study, we investigated the spatiotemporal variability of LULC and its impacts on LST in the Shigar district, utilizing Landsat data from 1993 to 2020. To study the variable LST, thermal bands of Landsat imagery were used. LULC was determined by classifying the images using the supervised maximum likelihood classification method. The vegetation and snow cover were also extracted by using the indices of the Normalized Difference Vegetation Index (NDVI) and Normalized Difference Snow Index (NDSI), respectively. The results showed that the Shigar district had experienced severe land cover variations in the years of 1993, 2003, 2010, and 2020. Specifically, the agricultural area gradually increased from 1993 to 2020. The forest/vegetation cover also increased in the study area. In contrast, snow cover and water bodies were drastically reduced during this period. The overall vegetation increased within the region and the LST values were found to be decreased in 2003 and 2010, whereas the LST rose in 2020. In addition, the correlation between NDVI and LST was found to be significant negative in areas with high vegetation cover. Conversely, it was weakly positive in other areas with minor vegetations. These findings suggest that green cover plays a crucial role in regulating temperature. Additionally, a negative correlation between LST and NDSI was observed with rising elevation. This study will be helpful in landscape and urban planning, watershed management, and policymaking for climate change variability.