[A-CG38] Dynamics of Oceanic and Atmospheric Waves, Vortices, and Circulations

[ACG38-P07] Wave observation by drifting buoys and the effect of currents on the observation

*Yukiharu Hisaki¹ (1.University of the Ryukyus)

Keywords:Wave height, Wave period, Drifting buoy

Drifting buoys can observe wave data far from land and in strong current area. The dependence of the difference between ERA5 wave data and buoy data on surface current speed derived from the drifting buoy positions was evaluated. The ERA5 reanalysis wave data does not account for the effects of currents. The difference between ERA5 wave heights and buoy-measured wave heights increases with increasing surface current speed; the ERA5 wave heights are significantly underestimated when there is an opposing current with respect to the mean wave direction. On the other hand, it is overestimated in the case of following current with respect to the mean wave direction. The maximum difference was about 20%. The wave period from drifting buoys also had differences from the ERA5 reanalysis wave period in the case of oopposing and following currents, mainly due to the Doppler shift.

Reference
Hisaki Y. 2023. Use of drifting buoys for wave observation: Effect of current on wave data. Deep Sea Research Part I: Oceanographic Research Papers. https://doi.org/10.1016/j.dsr.2023.103986.