SeaWiFS and MODIS-Aqua data used in this study were produced by the SeaWiFS Project at the Goddard Space Flight Center and obtained from the Goddard Distributed Active Archive Center. The work was supported by the Program of Basic Research № 23 of the Presidium RAS and by the Russian Government (Grant No.11.G34.31.0078) for research under supervision of the leading scientist at the Russian State Hydrometeorological University.