Oil spill trajectory forecasting and backtracking using surface currents from high-frequency (HF) radar technology

In the framework of the Spanish research project OCTOPOS (Ocean Technologies for Observing and Prediction of Oil Spills) the capabilities of HF radar systems for oil spill operations are explored. To achieve this objective, an oil spill prediction and backtracking system using HF radar currents has been used to analyze the benefits of this technology for forecasting and backtracking of oil spills. The core of the system is the TESEO oil spill transport model. The performance of the system has been tested using drifter buoys deployed during the “DRIFTER Exercise” (AMPERA Eranet, VI Framework Programme). Using the database collected during this exercise, the TESEO transport model has been used for two purposes: (1) the simulation of the trajectory of the buoys (forecasting) and (2) the backwards simulation in time to know, given the final position of the buoys, where they came from (backtracking). In order to study the contribution of HF radar currents, simulations have been performed using different forcings: (1) HF radar currents, (2) HF radar currents and numerical wind data and (3) numerical wind and currents data. The analysis performed shows that simulated trajectories are more accurate when using HF radar currents. The RMSE of the simulations calculated with HF radar currents is reduced by approximately 40-60% in comparison with the RMSE obtained using wind and currents provided by numerical models. The backtracking analysis also shows a good agreement. In this case, at the end of the simulation a distance of 1.58 km between the actual and the simulated buoy position is found. These results show the positive contribution of HF radar currents for trajectory analysis, and demonstrate that these data are of value for trajectory analysis of oil spills or floating objects.