Application of Sentinel-2 satellite data for monitoring snow cover in territory of Rila mountain, Bulgaria

In the present study, optical satellite data from Sentinel-2 MSI for a period of 10 years, for the month of April, from the territory of Rila Mountain were used. For each year of the selected time period Normalized Snow Difference Index (NDSI) was generated for each month April and the dynamics of the spatial distribution of snow-covered areas was observed based on the values derived from the applied NDSI index. Individual threshold values were determined for each generated index and results were obtained including the estimated snow-covered areas during the study period. The results on the dynamics of snow cover in the Rila Mountain region are of great importance, as it is the highest mountain in the Balkans and can serve as a target indicator for monitoring climate change and global warming at local and regional level. The results obtained in the study can be used and integrated for ongoing observations, studies and scenarios on the climate change impact on hydrology, agriculture, forestry, biodiversity etc. at local and regional level. The obtained results and the observed negative trends of snow cover dynamics for the selected temporal period can be applicable for other mountainous regions on the territory of Balkan Peninsula and areas with similar snowpack loss and climate conditions. In addition, they could be of great help and guidance for further analysis and modelling of climate change impact on snow cover distribution.