Abstract
Under the WindSYS project, we analyzed acoustic data from the Hywind Tampen floating offshore wind farm, consisting of 11 spar-buoy-supported turbines, each rated at 8 MW. Operational noise from one turbine revealed frequencies concentrated below 400 Hz, with tonal features between 25–80 Hz linked to rotational speed. Median one-third octave band levels below 400 Hz ranged from 95–100 dB re 1 μPa at ~500 m, comparable to noise from fixed offshore turbines and Hywind Scotland. Noise levels strongly correlated with wind speed and moderately with wave height, while impulsive sounds during high winds were linked to mooring lines. Source levels (25 Hz–20 kHz) increased with wind speed, consistent with findings at Hywind Scotland.