The atmospheric radiative transfer model SCIATRAN [V. V. Rozanov et al., 2002; A. Rozanov et al., 2005, 2008] was extended to include the radiative transfer within the ocean. This was done by including the inherent optical properties of water, and additionally extending the data bases by in-situ measurements of the optical important properties. To evaluate the quality of the coupled version the model has been compared to MERIS TOA reflectances and reflectances at the top of the surface water by using known input parameters (chl-a concentration, salinity, temperature and depth) from the BOUSSOLE time series measurements [Antoine et al., 2008], and informations about aerosols from AERONET at the corresponding station in Villefranche (optical thickness, phase functions, single scattering albedo and extinction coefficients; PI: David Antoine). The results of different sites and seasonal settings (phytoplankton blooms and non-blooms, varying particulate matter concentrations etc.) look very promising for the SCIATRAN model to capture the RT back to the top of the atmosphere. This will improve both the retrieval of different PFTs from high spectrally resolved satellite data as the retrieval of various atmospheric trace gases, such as BrO, NO2, and glyoxal over ocean water.