Improved Drift Forecasting in Coastal Waters (IDFCW)

The need for new forms of surveillance of territorial waters and the ability to detect potential risk events and initiate rapid response action has increased with the rise in global terrorism. In any response strategy to enable rapid prediction of the pathways of floating objects or dispersed fluids it is necessary to have accurate forecasts of surface sea state and currents available. It is well known that predicted currents from existing operational ocean forecasting models suffer a reduction in forecasting skill in coastal waters. This has serious consequences for rapid-response spill forecasting and search and rescue (SAR). A UK company, BMT, is responsible for the UK national search and rescue support system SARIS. This proposal, between Proudman Oceanographic Laboratory and BMT, has two aims a) to demonstrate improvements in state-of-the-art drift forecasting through a better understanding of the value of incorporating real-time currents into drift forecast models in coastal seas and b) to give recommendations for improving the accuracy of forecast currents. The POL Coastal Observatory in the Irish Sea provides the framework for this evaluation. We will run a test operational period in which forecast currents will be used in BMT model systems to simulate typical spill and SAR scenarios and tracked drifters released within the Coastal Observatory during the operational period. We will explore the value of assimilating the surface currents measured by the Coastal Observatory HF radar into these systems and we will run a coupled surface wave-current model to explore the impact of wave-current interaction on forecast coastal currents. The results will help to establish key research issues and define a basis for improving operational forecasting of coastal currents around the UK.