Investigation of changes in snow cover and determination of snowmelt line in mountainous areas using MODIS images and NDSI index (Case study of Zagros glaciers)

considering that one of the most important problems in the detection of snow phenomena using optical satellites, cloud segregation and snow, we used to identify and eliminate cloud surfaces using cloud behavior in different wavelengths by defining the normalized difference index in the modis data. then, the snow maps of zagros province of and were collected using images of modis daily in 1392 - 1393 for a five - day period, using our results to estimate snow melting in this period, and at the end to better represent the melting dynamics of snow melting the snow melting map with digital elevation model (SRTM). For this purpose, it is 100 m due to the resolution of the SRTM image. we decided to convert the modis image resolution power into 100 meters using the resampling method and then we integrated the data layers together with the combination of images and the height classification on the data layers, which, in addition to the dynamic representation of snow - melting snow, shows the height distribution of snow melting across