Sea wave characteristics along Zhejiang coast based on buoy observations and ERA5 data
Analysis on wind wave and swell characteristics of Zhejiang coast is carried out based on two buoys,Observations offshore Zhoushan and Wenzhou,and the ERA5 reanalysis data,with emphasis on significant wave heights(SWH),wave periods(WP)and risk indices of wind wave.Results show that the ERA5 data is basically consistent with the buoy observations.Wind wave and swell generally occur under strong breezes of≥10.8 m/s and light winds of below 4 m/s respectively.Wind wave mainly happens with prevailing winds from NNW,NW and N at the Zhoushan buoy,and N,NNE and NE at the Wenzhou buoy.The months with high frequency of wind wave are usually in winter half year,from January to March and from November to December,closely related to cold air masses.Monthly wave danger index shows that both buoys have a low risk level from May to June,and a high risk level from August to October.The ERA5 fields show wind wave in August is closely related to typhoon circulation,and SWH can be up above 4 m,while SWH of wind wave in winter and in months September and October is mainly between moderate and rough,and it displays higher wind wave elements along the southern Zhejiang coast than the northern coast.Cold air masses hold the widest coverage with wave risk above level Ⅱ,but only typhoons can cause wave risk of levelⅠin a large coverage of the coastal areas of Zhejiang.
万方数据
维普
