Understanding the variability of Chlorophyll (Chl) concentration through aquatic remote sensing over the coastal waters is very difficult through spatial low resolution sensor images. The Sentinel-2A/B from European Space Agency is specifically designed with spatially high resolution satellite images (30/10 m) which can be easily adaptable for monitoring the variability of Chl over the coastal waters. In this study, satellite-derived dataset from high resolution satellite images of Sentinel-2A/B was used to understand the spatio-temporal patterns of Chl in the Gulf of Manner. The standard Chl model based on the OC algorithm was used to estimate the Chl from remote sensing reflectance (R<inf>rs</inf> ). The study area is located in Gulf of Mannar, India where the coastal waters are dominated with the chlorophyll which are to be monitored using the Sentinel-2A/B images. Results obtained from the images allow to track the Chl variability in coastal waters. The spatio-temporal patterns observed from the Sentinel-2A/B images can be effectively useful for understanding the changes of Chl over the Coastal waters. © 2022 Elsevier B.V., All rights reserved.