Under the influence of swell waves, the Wave Coherent (WC) stress can drive the deviation of the wind profile from the Monin–Obukhov similarity theory (MOST), thereby increasing the uncertainties of the drag coefficient. From the turbulent perspective, the turbulence that behaves as a k^-b1 power law other than the k^-5/3 power law in the spectra maintains the wind profile, with exponent b₁ changing from 1 to 1.67. In this study, if the k^-b1 power law can be modulated by swell waves is explored. By considering the WC stress in the spectral budget of the Turbulent Kinetic Energy (TKE), this study reveals that the WC stress and the turbulent stress can both affect the exponent under unstable conditions: compared with the absence of the wave effect, the smaller the turbulent stress is, the smaller the exponent and the larger the intersection between k^-b1 and k^-5/3 has. The dependences of the exponent and the interaction on the WC stress have a similar trend: their deviations from that without the wave effect increase with the WC stress. The observations from a fixed platform in the South China Sea are used to confirm these findings. Additionally, using the spectra of the momentum flux, the reason behind the wind profile deviation from the MOST is analyzed theoretically.
 

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