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The Himalayan glaciers, being unique in nature, need more detailed study over their evolution in the Himalayan glacial zones. A methodology has been developed using two-dimensional signatures from synthetic aperture radar (SAR) C-band dual-polarized data. A linear decision rule-based model has been generated using the signatures and the result further filtered by the use of a digital elevation model (DEM) to delineate glacial zones in the Himalayas. The advantage of using cross-polarized data is the addition of extra information from the volume of the glacial mass. Some important prerequisites for the analysis are SAR image ortho-rectification and calibration, glacier boundary delineation, and the development of sites for collecting SAR backscattering signatures from glaciers along the profile. The study deals with the evolution of glacial snow cover and glacial zones/facies in the Himalayan region under a subtropical humid climate from the ablation to the accumulation season. SAR images from 15 July 2012 to 30 June 2013 over the Gangotri and Mana glaciers were evaluated with the developed model. The identification of a superimposed zone during the ablation season is among the key results. The identified snowlines and other boundaries of glacial facies are studied on a temporal scale. The highest snowline altitude of Mana was recorded at 5768 and 5194 m for the Gangotri glacier in 2012. SAR data are also important in identifying glacial zones buried under winter snow cover. The results obtained are useful in regard to further glaciological studies of the Himalayan glaciers. [ABSTRACT FROM PUBLISHER]

Imaging radars provide information that is fundamentally different from sensors that operate in the visible and infrared portions of the electromagnetic spectrum. The Indian Space Research Organisation (ISRO) has launched a multi-mode, multi-polarization Synthetic Aperture Radar (SAR) on-board Radar Imaging SATellite-1 (RISAT-1) on 26 April 2012. Various data products from RISAT-1 SAR are now going through calibration-validation (cal-val) phase and soon will be available for the global users for operational and research purposes. In this regard, algorithms are being developed to retrieve various parameters in diverse application areas. This article deals with the in-house algorithm development for studying different resources using initial available data of RISAT-1. [ABSTRACT FROM AUTHOR]