Wave characteristics analysis in Bohai Sea based on ECMWF wind field

In order to achieve further understanding of the characteristics of wind waves in the Bohai Sea, the SWAN (Simulating Waves Nearshore) model is applied to investigate the wave characteristics in Bohai Sea for the period from 1993 to 2012. The SWAN model is driven by the wind data from ECMWF (European Center for Medium Range Weather Forecasts). Comparison of the ECMWF wind data against the field measured data shows that the ECMWF wind data underestimates wind speed over the Bohai Sea, though the overall trend and dominant directions are consistent with the observational data. Thus, the ECMWF wind data was corrected according to the filed measured data before it is input into the SWAN model. The SWAN model is calibrated using both the short-term and long-term field measured data, and the model results agree well with the measured data. The temporal and spatial distribution of wave height, averaged period and wave direction were analyzed. It shows that our results are generally agree with that of the previous studies. However, the previous studies overestimate the significant wave height by 10 cm in three major bays in Bohai Sea and by 1-10 cm in Bohai Center and the Bohai Strait.