Wave characteristics and wave energy resource assessment of the waters bordering China

Wave energy is a clean and renewable marine resource with great development potential. The China Sea, including the Bohai Sea, Yellow Sea, East China Sea and South China Sea, has complex marine conditions. This study aims to clarify the wave characteristics and spatiotemporal distribution of wave energy resources in the China Sea, providing a scientific basis for its rational development and utilization. Using 30-year ERA5 wind field data (1995–2024) as input, the SWAN wave model was adopted to numerically simulate the wave field in the China Sea. The multi-year, seasonal, and monthly average wave and wave ennergy characteristics were analyzed, and wave energy resources was evaluated with wave energy rose diagrams at characteristic points. The Bohai Sea and Yellow Sea had low annual mean wave heights mostly below 1.2 m, the East China Sea 1.2–1.7 m, and high-latitude South China Sea up to 2 m. Most regions except the Bohai Sea and northern Yellow Sea had annual average energy flux densities exceeding 4 kW/m² , especially near Taiwan Island and South China Sea. Wave energy was richest in winter, followed by autumn, and poorest in spring; The characteristic points the dominant direction was east-northeast, with density mainly distributed in 1–10 s wave periods and 0–5 m significant wave heights. The China Sea has substantial wave energy potential. The spatiotemporal and directional characteristics identified provide important references for the design, planning and utilization of wave energy conversion projects in the region.