Estimation of changes in snow depth in Ardabil and Sarein city using Sentinel1 satellite data with Radar interferometry method

Snow as an important part of the hydrological cycle, is considered to be a major source of fresh water in many areas above 45 degrees latitude, so it is important to study and measure changes in snow levels as an important source of water supply.In the present study, first using Sentinel2 optical satellite images in 1397 in Ardabil and Sarein, snow cover level was obtained through NDSI index, then in order to monitor snow depth changes in the study area, SentinelA1 macro images and DINSAR technique were used. Finally, in order to validate the snow depth maps extracted through radar images, the snow depth data in land snowfall stations were compared using linear regression in MATLAB software. The results of linear regression with a generalization coefficient of 85% and the results of error statistical indicators are equal to 0.86-MSE, 0.165-BIAS, 0.924-CORR and RMSE equal to 0.043. The correlations between ground data and snow depth estimation maps show a high degree of correlation. This result is statistically significant at 99%. The results of the present study showed that according to the climatic conditions of the study area, the values of snow depth related to January with a maximum amount of 33 cm and the lowest values of snow depth in March with a minimum of 10 cm. The lowest snow depth was in the eastern slopes and the highest in the western slopes.