Drifter trajectory tracking experiment and analysis with multi-frequency HFSWR in the East China Sea

We conducted the drifter trajectory tracking experiment for two drifters in the East China Sea, in which the currents were detected by two multi-frequency HFSWRs using the Lagrange-tracking method. The tracking drifter trajectory shows good agreement with the GPS records by qualitative and quantitative analysis that indicates that drifter tracking by HFSWR is valid. In the 12-hour tracking for drifters P ₁ and P ₂, the average errors are 1.84 km, 1.73 km, and the maximum errors are 3.52 km and 3.12 km, respectively. The current measurement is evaluated by an acoustic Doppler current profilers (ADCP) in-situ observation, and it is the first multi-frequency HFSWR ocean surface monitoring experiment in China. In addition, the main aspects (HFSWR current measurement error, wind, and wave) influencing the tracking accuracy are discussed, and especially the wind factor’s impact is analyzed through the wind filed data.