High Resolution X-band SAR Data for Snow Studies in Manali Area of Western Himalayas

State-of-the-art high resolution active remote sensing imaging radar, TerraSAR-X, is having all-weather and all-time data acquisition capability. It is a promising tool for mapping snow and glaciers in mountainous region. The current study has been done using dual polarization (HH/VV) Synthetic Aperture Radar (SAR) data of TerraSAR-X (TSX), to estimate the snow physical properties (snow cover, snow wetness), in Manali subbasin of Himachal Pradesh, India. A modified snow wetness inversion algorithm of [16] is implemented on space borne imaging radar-X-band 1 m high resolution spotlight mode SAR data of TerraSAR-X. This inversion algorithm has been successfully implemented in Matlab and Mathematica. Mask for forest, built area, layover and shadow has been considered in estimating snow parameters. Overall accuracy in terms of R value comes out 0.85 for snow wetness based on ground truth data for subset area of Manali sub-basin. Also, generally it is generally difficult to visually interpret the SAR images of lower resolution, but high resolution (1 m) of TSX give high quality SAR images which can be used easily for visual interpretation. Some inferences were drawn by visual interpreting the SAR image along with texture analysis of SAR images in Manali subbasin, especially in identifying forests, glaciers, river, bridges and settlements. This work has been done as part of TerraSAR-X science service project, sponsored by DLR. KeywordsHigh resolution X-band, Image processing, Polarimetric SAR, Snow wetness, Inversion model, Manali.