Spectral features of ocean colour radiometric products in the presence of cyanobacteria blooms in the Baltic Sea

• Published in: Remote Sensing of Environment
• Main Authors: CAZZANIGA Ilaria, ZIBORDI Giuseppe, MELIN Frederic
• Language: English
• Published: ELSEVIER SCIENCE INC 2023
• Subjects: Lambda; Aerosol Robotic Network
• Online Access: https://publications.jrc.ec.europa.eu/repository/handle/JRC130318; https://www.sciencedirect.com/science/article/pii/S0034425723000159; https://doi.org/10.1016/j.rse.2023.113464

Cyanobacteria blooms are recurrent in the Baltic Sea with frequency and intensity increasing with temperature. By relying on autonomous multispectral measurements from the Ocean Colour component of the Aerosol Robotic Network (AERONET-OC), this study presented an unprecedented dataset of remote sensing reflectance RRS(lambda) spectra acquired during cyanobacteria blooms in the Baltic Sea and investigated the temporal evolution of the in situ RRS(lambda) during these blooms. Additionally, it assessed operational satellite Ocean Colour RRS(lambda) products from the Ocean and Land Colour Instrument (OLCI) and Moderate Resolution Imaging Spectroradiometer (MODIS) in the presence of cyanobacteria, for which only qualitative evaluation are available from previous studies. The comparison of in situ and satellite derived RRS(lambda) showed poor agreement, with differences particularly pronounced at the blue centre-wavelengths. Nevertheless, band-differences such as RRS(560)−RRS(620) and RRS(560)−RRS(665) for OLCI, or RRS(547)−RRS(667) for MODIS, appeared robust indicators of the presence and evolution stage of cyanobacteria blooms in Baltic Sea waters while not being sensitive to other algal blooms. JRC.D.2 - Ocean and Water