POSTER SESSION 2
10:30–12:30, Tuesday, September 15
Poster Session | 1 | 2 | 3 | 4 | Schedule at a Glance
ABSTRACT 1171 | POSTER 98
EVALUATING TRISHNA VNIR SPECTRAL CONFIGURATION FOR SPM AND CHLOROPHYLL-A RETRIEVAL IN OPTICALLY COMPLEX WATERS
The TRISHNA (Thermal infraRed Imaging Satellite for High-resolution Natural resource Assessment) mission is jointly developed by the Centre National d’Études Spatiales (CNES) and the Indian Space Research Organisation (ISRO). It carries a VNIR sensor providing bands at 485, 555, 670, and 860 nm (FWHM: 70, 70, 60, and 40 nm respectively) for ocean colour retrieval, and a Thermal Infrared sensor for Sea Surface Temperature (SST) estimation, at 60 m spatial resolution and a 3-day revisit time. It offers a unique opportunity to simultaneously derive water colour constituents along with SST and significant potential for advancing the understanding of coastal processes such as sediment dynamics, phytoplankton variability, and river plume dispersion. As a first step towards this integrated coastal monitoring framework, this study presents the development and validation of algorithms for Suspended Particulate Matter (SPM) and Chlorophyll-a (Chl-a) retrieval using our in-situ and the GLORIA datasets. The developed red-NIR-based semi-analytical SPM algorithm outperformed globally established models utilising equivalent spectral bands, achieving R² = 0.72, RMSElog = 0.359, Bias = -7.5%, and MAPE = 66.3%. The Chl-a retrieval, however, proved challenging due to the optical complexity of case-2 coastal waters, the lack of red-edge spectral sensitivity, and the broadband nature of TRISHNA VNIR bands. These findings establish a foundational framework for TRISHNA-based coastal water quality retrieval, highlighting both its capabilities and limitations, and also emphasize the need for advanced approaches, including machine learning framework integrating spectral, thermal and contextual information, to improve Chl-a estimation in optically complex waters.
Dilipkumar Jayaraj, Laboratoire d’Océanologie et de Géosciences, [email protected], https://orcid.org/0000-0002-8061-0663
Cédric Jamet, Laboratoire d’Océanologie et de Géosciences, [email protected], https://orcid.org/0000-0001-6988-6506
Charles Verpoorter, Laboratoire d’Océanologie et de Géosciences, [email protected], https://orcid.org/0000-0002-5134-4124
Poster Session | 1 | 2 | 3 | 4 | Schedule at a Glance
