The concentration and composition of phytoplankton, coloured Dissolved Organic Matter (cDOM),
and the Suspended Particulate Matter (SPM) composition are the main factors that influence the
optical properties of natural waters [Prieur and Sathyendranath, 1981], producing the apparent
water colour [Effler and Auer, 1987]. A comprehensive study of the absorption and scattering
properties of the main visible water constituents has been given in Gordon and Morel [1983]. They
conclude that the water-leaving remote-sensing signal is mainly a function of: