ProVal : First data from a new Argo profiler dedicated to high quality radiometric measurement

Following the recommendation of the International Ocean Color Coordinating Group in 2011 (IOCCG report #11), the Laboratoire d’Oceanographie de Villefranche (LOV) has developed a new profiling float dedicated to the validation of satellite ocean color remote sensing data. Taking advantage of our experience in both Argo floats and radiometric measurements, we have developed the ProVal float. This new float has a two-arm design that allows sensor redundancy and mitigation of shading by the float through using the radiometer best placed with respect to the sun. ProVal measures downward irradiance and upwelling radiance at seven wavelengths with the highest quality currently achievable with this type of radiometer. It also measures the downward Photosynthetically Available Radiation, the fluorescence of Chlorophyll-a and of Colored Dissolved Organic Matter and finally the backscattering at 700nm. ProVal is able to monitor all year round these apparent and inherent optical properties of the water column simultaneously with ocean color satellite observations.

After a description of the original concept of our platform based on a new float designed by NKE (PROVOR CTS5) combined with a new acquisition board developed on our specifications, we present initial data from this float taken during several deployments in the Mediterranean Sea. Together with results on sensor aging over deployments, ProVal data are compared with those acquired by other platforms dedicated to Ocean Color measurements (buoy measurements from the BOUSSOLE site and satellite ocean color observations). Perspective of future deployments will be also presented.