A BIO-OPTICAL AQUATIC DATABASE FOR THE REMOTE SENSING OF WATER QUALITY IN COASTAL AND INLAND WATERS OF BRAZIL

Monitoring water quality (WQ) in a vast country as Brazil demands significant effort and financial resources. Remote sensing (RS) plays a crucial role in optimizing this monitoring by providing a synoptic view of aquatic environments with high spatiotemporal resolution. However, developing high-quality WQ products using RS requires a comprehensive and extensive database that includes concurrent aquatic reflectance data and WQ variables (e.g., Chlorophyll-a, Secchi Disk Depth). Such databases enable the application of advanced semi-analytical and machine learning models to capture the bio-optical complexity of these waters. Building this database requires a collaborative community effort.  This paper presents the first compilation of bio-optical datasets for the Brazilian coastal and freshwater ecosystems. This initiative involves 14 institutions and currently comprises 3,058 unique stations across more than eighty lakes, rivers, reservoirs, and coastal waters in Brazil. Our dataset reveals that the Amazon Basin is well represented with over 1,600 stations; however, the central-west region, particularly the Pantanal, still lacks adequate representation in these bio-optical datasets. The final dataset is still under development and will be submitted to a Data journal soon.