Potential of EOS-04 C-band Synthetic Aperture Radar in Identifying Oceanic Rain Cells

Indian Space Research Organisation (ISRO) launched Earth Observation Satellite (EOS-04) on 14th February, 2022, which is equipped with C-band Synthetic Aperture Radar (SAR) payload. As rain seriously limits C-band SAR performance and introduces error in determining actual ocean surface features, identification and interpretation of rain induced signatures in recently launched EOS-04 are crucial. Thus, the present study is formalized for EOS-04 SAR with 2 objectives (i) to demonstrate its potential in locating oceanic rain cells and (ii) to strengthen the knowledge of rain induced signatures over the North Indian Ocean (NIO). For this purpose, 2 images of SAR acquired on 5th May, 2022 over the Bay of Bengal and 24th May, 2022 over the Arabian Sea are utilised. Footprints associated with high and low rainfall activities are well marked in both the images of SAR. Further, the role of ocean surface wind in evolving rain signatures is also notified. The normalised radar cross section (NRCS) shows large variation over the rain affected regions and signatures are coupled with both dark and bright patches. The outcomes of the study are not only useful to understand the physical processes embedded with the rain signatures but also theoretical aspects associated with them to strengthen the knowledge of EOS-04 C-band SAR images for future aspirations over NIO.