Description : The present research proposal is submitted under theme B.3. (Marine management) of the "Earth observation by satellite" (TELSAT 4) of the program for scientific support for a policy of durable development. The research has the objectives: 1. To improve the bio-optical algorithms used in the ocean colour model existing at MUMM by incorporating the latest theoretical advances and by performing a calibration of the model specific to the Belgian coastal zone. This calibration is based on sets of inherent optical properties and corresponding water constituents measured in a series of seaborne campaigns. 2. To improve the use of the ocean colour products and to enhance the processing chain by incorporating the characteristics of new sensors (MODIS, MERIS, etc). 3. To prepare higher level products combining satellite imagery, in situ measurements and/or the results from mathematical models, and to tailor such higher level products to the needs of already-identified end-users. This proposal represents an exension of the work already carried out in the project "The multicoloured North Sea" (T4/DD/004), which ends in November 1998