Estimating Snow Water Equivalent Using Sentinel-1 Repeat-Pass Interferometry over Idaho

The Snow Water Equivalent (SWE) is identified as the key element of a snowpack that impacts rivers’ streamflow and water cycle. Active and passive microwave remote sensing methods have been used to retrieve SWE. Interferometric Synthetic Aperture Radar (InSAR) has been shown to have the potential to estimate SWE change. In this study, we apply this technique to a large time series of Sentinel-1 data from winter 2021. The retrieved SWE change observations align really well with in situ stations with 0.82 correlation and 0.76cm RSME. The total retrieved SWE also align really well with 16 in situ values in the scene with less than 20cm SWE error. On the other hand, the retrieved SWE using Sentinel-1 data is highly correlated with LIDAR snow depth data with correlation of more than 0.5.