In the frame of MARRE Program (November 2019), the KATERINA II system was integrated in the floating measuring station of the POSEIDON system (station ‘ATHOS’) for continuous measurements of natural and artificial radioactivity of the surface water masses.

More specifically, the detection system will provide the activity concentration of natural radionuclides (Radon, Thorium and Potassium) as well as artificial radionuclides (Cesium) after and before rainfall events. In particular, the data will be used to evaluate the state of the sea due to Dardanelles water flow from the Marmara Sea as well as to calibrate existing methods of measuring sea surface radioactivity from satellites. In the case of rainfall events the data will be used to study the interaction of rainwater (using radon as a tracer) with seawater (using potassium tracer).

The KATERINA II system provides the aforementioned radionuclides in the measured spectrum at once and in a resolved phase supporting the interpretation of the processes (such as mixing of water masses). The radioactivity data will be combined with physico-chemical parameters given by the floating measuring system in the defined time lag.