Daily gridded products provided in delayed time for the year 2019 produced in the frame of the e-shape project https://e-shape.eu . The time series of NFAI products produced since February 2022 to date are provided through Aviso+ as part of the SeSaM project https://www.spaceclimateobservatory.org/sesam. Each map represents the sargassum presence index averaged over one week and one day at 1 km or 350m resolution. Provided by OLCI instruments onboard Sentinel-3A and Sentinel-3B.