Ocean Colour and CZCS Applications in and Around Europe

Abstract

Ocean optics have an important place in the European oceanographic tradition. This has led to substantial contributions to the Coastal Zone Color Scanner (CZCS) experiment, with the development of algorithms and models to handle data calibration, atmospheric correction, pigment value retrieval. Special requirements have been imposed on such developments by the peculiarity of the European basins. The Seas of Europe present an heterogeneous mixture of water constituents, including different planktonic populations, dissolved organic compounds, and a considerable suspended load. As a consequence, their optical properties range from those of Case 1 waters, where planktonic agents provide the dominant pigments, as in the open Mediterranean Sea or in the North Atlantic Ocean, to the most typical Case 2 waters of the North Sea or of many near-coastal areas, which in general are not optically dominated by plankton alone, but also by other suspended particulate and dissolved organic compounds, partly because of the impact of human activities, resources exploitation, and environmental pollution. The complex ensamble of environmental conditions to be approached has determined the development of specific bio-optical, reflectance, and light/photosynthesis models, as well as the application of methods such as factor analysis and inverse modeling techniques for the evaluation of CZCS data. The major applications of CZCS in and around Europe range from early descriptive oceanography work, looking at pigment distribution as related to circulation features, to the quantification of pigment concentration patterns, plankton dynamics, as well as coastal runoff and river plumes.