Technical elements and potential application of spectroscopy for ocean monitoring

Enforced regulations at sea and future monitoring programmes require advanced systems for the measurement of physical and chemical parameters of seawater. Real-time and in-situ techniques are especially needed for the acquisition of data and for research on coastal pollution processes. The development of an all-optical in-situ measuring system is presented. It is a joint European project to test the feasible of using fibre-optic chemical sensors for sea-water analysis. The measurements are based on the spectroscopic methods fluorescence, absorption, Raman scattering and refraction each using innovative fibre optical chemical sensors (optodes). The optodes are linked to a core instrument for spectroscopic analysis. Light sources, optodes, spectrometer and detectors will be underwater with only the control unit and data processing on board. For the demonstration stage heavy metals, chlorinated hydrocarbons, aromatic hydrocarbons and salinity will be measured. Physical principle, sensing configuration and technical elements of this system are discussed along with first laboratory results and potential applications