Application of Remote Sensing & GIS to estimate the changes of surface temperature in Ninh Thuan

Abstract

Advanced remote sensing technology enables the detailed analysis of surface temperature variations across large areas, overcoming the limitations posed by the number of meteorological stations. This research focuses on applying remote sensing techniques and GIS to create surface temperature maps for Ninh Thuan province during the 2018–2021 period. By employing satellite imagery of Landsat and Sentinel, the study assessed changes in surface temperatures and their relationship with vegetation cover. The findings revealed that surface temperatures in the region ranged from 15.0°C to 44.0°C. Urban areas, residential zones with limited greenery, and vacant lands exhibited higher temperatures, typically between 27.1°C and 35.0°C. In contrast, mountainous areas with dense vegetation showed significantly lower temperatures. The study utilized a method to convert digital values from satellite images into spectral radiance values, which were then processed using computational algorithms to calculate surface temperatures. The NDVI vegetation index was employed to evaluate vegetation density and its correlation with temperature. Over the study period, vegetation cover decreased by 3.5%, while vacant land increased by 1.7%, and residential areas expanded by 0.35%. These shifts in land use contributed to increased thermal radiation and higher surface temperatures. Maps of land cover and surface temperature demonstrated a notable rise in areas with temperatures exceeding 37°C, especially in coastal and lowland regions where urban development and limited vegetation were significant factors. The research validates the feasibility and efficiency of using remote sensing data to monitor surface temperature changes across extensive areas. The results not only offer insights into temperature trends in Ninh Thuan but also provide a critical scientific basis for proposing strategies to mitigate the effects of rising surface temperatures. Such strategies are essential for achieving sustainable development in the face of escalating climate change challenges.