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Indian Space Research Organisation (ISRO) has successfully launched its second civilian C-band Synthetic Aperture Radar (SAR) mission onboard Earth Observation Satellite-04 (EOS-04). The SAR data monitors and measures various atmospheric features and parameters. In this paper, we report on the investigation of EOS-04 data for several atmospheric phenomena. One of the crucial parameters for studying atmospheric manifestations in SAR data is ocean surface winds and an algorithm for its retrieval has been developed using EOS-04 data. The wind speed products thus generated are evaluated using observations from the Advanced Scatterometer and subsequently used to study atmospheric phenomena like boundary layer structures. The EOS-04 SAR data is also demonstrated for studying structures associated with tropical cyclones, coupling of rain and wind imprints and distinct signatures of an atmospheric front. The study outcomes are used to interpret atmospheric phenomena and understand backscattering signals from EOS-04 SAR. This indicates the possibility and potential of a gamut of atmospheric phenomena that can be probed using EOS-04 SAR data. [ABSTRACT FROM AUTHOR]

EOS-04 (Earth Observation Satellite-04), launched on 14 February 2022, is a follow-on mission to Indian Space Research Organisation’s first synthetic aperture radar (SAR) satellite RISAT-1. It is capable of imaging in either side of the track with incidence angle range from 12.2° to 55.1°. Onboard SAR system supports variety of resolution and swath requirements and can operate in various modes like StripMap, ScanSAR and Sliding Spotlight modes with various polarization combinations like linear, hybrid and full/quad polarimetry. EOS-04 is the first spaceborne SAR mission worldwide supporting full-polarimetry (FP) data acquisitions in ScanSAR modes. Availability of FP datasets in wide swath modes (ScanSAR modes) is a big step towards scientific analysis for various applications in a timebound manner. For enabling interferometric processing, EOS-04 orbits are being maintained within the baseline requirements of 500 m. EOS-04 has 17 days repetivity resulting in less temporal decorrelation to use the datasets for various deformation studies. In addition to this, analysis ready data (ARD) product, normalized radar backscatter (NRB) Gamma0 product, are introduced to minimize the user efforts for any immediate analysis. In NRB Gamma0 products, terrain induced variations particularly on hill-slopes affecting the brightness of the radar return is normalized by applying radiometric terrain correction (RTC) on SAR images. This paper discusses about the data processing aspects related to calibration, polarimetry, interferometry and NRB Gamma0 product generation. [ABSTRACT FROM AUTHOR]