Characteristics of global waves based on the third-generation wave model SWAN

Abstract Long-term wave data at a global scale are crucial for the studying characteristics of global waves, such as spatial distributions and extreme waves. These characteristics play significant roles in the design, construction, installation and operation activities of marine structures. Because of the limited resolution and coverage of instrumental measurements, the global wave hindcast is widely used. To develop this hindcast, the Simulating WAves Nearshore (SWAN) model is forced with the ERA-Interim wind database from 1979 to 2017 with a resolution of 0.25° in both longitude and latitude. The hourly wave parameters, such as the significant wave height and the mean period, are validated against buoy measurements over the Northwest Pacific Ocean, the Northeast Pacific Ocean and the Northwest Atlantic Ocean. Based on the 39-year simulated results, the spatial distributions of mean and maximal significant wave heights are analysed for all 39 years, every decade, 4 seasons, 12 months and special years; extreme waves are studied at the global scale and at every computational point.