Copernicus Sentinel-3/OLCI derived Phycocyanin (PC) concentration over the Tietê River cascade reservoirs, São Paulo, Brazil. Water quality parameter estimated using ACOLITE atmospheric correction and the algorithm developed by [Lima et al. (2025)](https://doi.org/10.1016/j.hal.2025.102836). This datataset is provided as Cloud Optimized GeoTIFF (COG).