Source: Journal of Geophysical Research: Oceans
The air-sea flux is an essential and complex turbulent process which controls the momentum, energy, and mass exchanges between the ocean and the atmosphere. The drag coefficient is a key parameter for surface wind stress, and it is known to have a non-monotonous dependence on surface wind speed.
Based on turbulent flux observations, Chen et al.  find that the drag coefficient has an asymmetric spatial distribution in different quadrants of a tropical cyclone which is attributable to the asymmetry of ocean waves during a tropical cyclone. The results highlight the importance of the ocean waves for air-sea fluxes. They also present a new challenge and a new avenue for a better simulation of ocean-tropical cyclone interactions, and the climate system.
Citation: Chen, S., Qiao, F., Zhang, J. A., Xue, Y., Ma, H., & Chen, S. (2022). Observed drag coefficient asymmetry in a tropical cyclone. Journal of Geophysical Research: Oceans, 127, e2021JC018360. https://doi.org/10.1029/2021JC018360
—Lei Zhou, Editor, Journal of Geophysical Research: Oceans