Investigation of wave characteristics in the Sanmen Bay under various typhoon paths

To investigate the wave characteristics in the maritime domain during typhoon conditions, this study focuses on the central region of Sanmen Bay in Zhejiang Province. Employing the MIKE21 SW model, we simulate six typhoon-induced wave processes and analyze the significant wave height and wave spectrum variations in Sanmen Bay under the influence of typhoons following different paths. The findings reveal that under typhoon influence, the significant wave height and wind speed in the Sanmen Bay maritime area exhibit a relatively consistent changing trend. Notably, during Typhoon “Matsa”, the maximum significant wave height in the study area exceeds 2 meters. In the peak impact period of the typhoon, wave energy distribution concentrates from the northeast to southeast. The wave energy spectra of landfall typhoon “Matsa” and post-landfall turning typhoon “Krosa” exhibit single-peaked dominance, primarily characterized by wind waves. Turning typhoons “Jangmi” and “Talim” display double-peaked spectra, indicating a combination of swell and wind waves, with wind waves playing a predominant role. The wave energy spectrum of westward-moving typhoon “Haima” features a single peak dominated by wind waves, accompanied by a minor presence of swell. For the open-sea turning typhoon “Trami,” the wave energy spectrum is single-peaked and dominated by swell.