Analysis of wave characteristics in the Northern Yellow sea based on field observations

With the increasing frequency of extreme weather events driven by global climate change, a comprehensive analysis of wave characteristics under extreme meteorological conditions is essential for improving the safety of maritime transportation. Previous research has predominantly focused on wave characteristics during typhoons, while studies on wave characteristics under frequent cold wave climates in mid- to high-latitude regions are still lacking. In this study, we used half-year wave data (March to September 2023) for the Northern Yellow Sea. We conducted a statistical analysis of wave characteristic values in this sea area and investigated the relationship between various characteristic wave heights, the mean wave height, and the significant wave height. A detailed analysis of the wave height, wave period, and wave spectrum during a typical cold wave event in April was performed to describe the wave characteristics and their variations in this area under extreme meteorological conditions. The results showed that the wave height distribution in this region exhibited a Weibull distribution, which fitted better than the Rayleigh and Gumbel distributions, especially in cases with high wave heights. The distribution of the wave period diverged as the spectral width increased, and the Sunfu and Gumbel distributions achieved better fitting under wide-spectrum conditions. The joint distribution of the wave height and period exhibited an inclined triangular pattern; however, discrepancies remained when compared with theoretical models, particularly for large wave heights and extended periods. Additionally, during cold wave events, the wave characteristics in the region exhibited a double-peaked spectrum as a result of the interaction between low-frequency swells and high-frequency wind waves. Our research results provide a reference for maritime navigation safety in this sea area.