TY  - JOUR
AU  - Hsu, Shih-Ang
PY  - 2025
DA  - 2025/01/15
TI  - On the Relation between Overwater Friction Velocity and the Wind Speed During Tropical Cyclones
JO  - Advances in Environmental and Engineering Research
SP  - 007
VL  - 06
IS  - 01
AB  - In the realm of marine meteorology, physical oceanography, and coastal and ocean engineering, the wind-stress across the air-sea interface plays a dominant role. However, under tropical cyclone conditions, there is no consensus for the formulation of the drag coefficient, Cd, in the literature. Based on the wind-gust method and the measurements from data buoy 42001 during Hurricane Lili, it is demonstrated that, U* = 0.073U10 - 0.44, which is valid up to wind speed 47 m s-1 and wind gust to 66 m s-1, here U* is the friction velocity and U10 is the wind speed at 10-m height. This formula is also supported by the atmospheric vorticity method. Applications for this proposed formula to estimate the variation of the wind speed with height and to determine the wind-stress storm surge or saltwater flooding during the most recent Hurricane Helene in 2024 are successful. In addition, it is found that Cd = (1.29Ln(Hs) + 0.27)/1000, which may be used to explain the behavior of the variation of Cd with the significant wave height, Hs. In order to further substantiate the proposed formula, more datasets during other tropical cyclones are incorporated for the validation.
SN  - 2766-6190
UR  - https://doi.org/10.21926/aeer.2501007
DO  - 10.21926/aeer.2501007
ID  - Hsu2025
ER  -