​​The Marine Optical Laboratory of the Joint Research Centre (JRC) in Ispra installed an AERONET-OC SeaPRISM radiometer on a unique site on Lake Varese to support satellite ocean color validation activities. The measurements from the instrument help to validate the fitness for purpose of data from satellites. 

​'The AERONET-OC network (operated by NASA) was set up to validate data on oceans from satellites. AERONET-OC stands for the Aerosol Robotic Network for Ocean Colour. The network relies on Cimel CE318T SeaPRISM sun-photometers which have been installed on fixed marine and inland-water structures such as offshore towers, lighthouses, oil platforms, and similar platforms. Each instrument autonomously measures both atmospheric optical depth and water-leaving radiance. The data is continuously transmitted to the network and processed to retrieve normalised water-leaving radiance and aerosol optical thickness.  

​Satellite ocean color validation requires long-term, standardised and autonomous in situ measurements collected under real operating conditions across a range of water types, so that atmospheric correction schemes and bio-optical algorithms can be checked against ground truth. 

​The SeaPRISM radiometer was installed by the JRC on one of the platforms of the Varese rowing club ‘Canottieri’. This new site on the small lake is unique and will contribute measurements on standardised water-leaving radiance and aerosol optical depth to the AERONET-OC network.