Snow Cover Estimation Using Sentinel-2 High Spatial Resolution Data. A Case Study: National Park Šar Planina (Serbia)

Abstract

Remote sensing, presented in the form of high-resolution satellite images, is essential in monitoring snow cover and the state of the environment. Due to the increase in the spatial resolution of the images, the Sentinel-2 mission improved the research of natural conditions and processes on the topographic surface. This paper presents changes in the snow cover of National Park Šar planina during 3 winter seasons: from December 2018 to April 2021. The study is based on the analysis of 33 satellite images where snow cover has been estimated using a combination of Normalized Difference Snow Index (NDSI) and S3 indices with suitable thresholds. According to the final results, the trend of decreasing the area of snow cover was observed. During the first season 91.75% of the study area was covered with snow, while in the next two seasons these percentages were lower - 79.94% and 72.84% retrospectively. The final result coincides with the trend of climate change, which is reflected in the increasingly intense warming of glaciers in the largest mountains and the decreasing amount of snowfall. It is believed that the obtained results will provide an adequate overview of the local population in terms of tourism and agricultural activities, as well as proper management of water resources in settlements that provide fresh water from reservoirs of mountain rivers that spring on the Šar Planina.