Cold Front Storm Surge Induced The Water Level In The Coastal Of Zhoushan

Storm surge is the most serious marine disasters in coastal area of China.Most of the severe coastal disasters caused by strong weather systems are storm related.There is two types in storm surge,including typhoon storm surges and storm surge induced by cold-air.Typhoon storm is mainly happened in summer and autumn,while,the storm surge induced by cold-air outbreaks in the winter and spring.Storm surge can occur almost all over the coastal waters of China,leading to damage of property and loss of lives.Storm surge has been an important subject of domestic and foreign scholars.Continue to explore the storm surge on the coastal areas for disaster prevention and mitigation,protecting people's lives is of great significance.The preliminary study of this paper is the influence of the storm surge induced by cold-air on the coastal water level in Zhoushan sea area.By analyzing the characteristics of the cold wave induced storm surge in Zhoushan sea area,using four main paths for the classification of the cold wave,and according to the different weather systems,we compared the generation of storm surges.Although there is only one observation station,but because the storm surge is a large-scale phenomenon,the analysis is still valid for the area.Combined with the meteorological parameters such as air pressure,air temperature,wind speed and so on,and the hydrological factors such as water level and water temperature between January 1 and April 30,2016,the influence of cold front passage on the coastal water level was studied.It is found that the air pressure descends and then rises abruptly.With the increase of the air pressure,the temperature drops abruptly.There were4-5 times when the wind changed direction prior to the cold front passage.At the same time,the wind speed increases.The water level rises before the strong cold air passage.The water temperature drops after the strong cold air passage and the decline of water level.The water level then gradually returns to the average.The water temperature also tends to return to the average state after the cold wave.Secondly,it also explores the characteristics and rate of change of the storm surge induced by cold-air.It is found that the fluctuation of the rate of increase in water is significantly increased during the cold front passage.The time of the extreme point is the date of the storm surge induced by cold-air who crossed.After of that,the rate is return to the previous average state.The change of the rate is very similar the wind.Wind plays a very important role in this progress.The increasing or decreasing rate of water depends on the wind who dominated in Zhoushansea area.With respect to the mechanism of coastal water level variations due to cold fronts,our quantitative analysis shows that wind is the dominant factor,followed by the air pressure.The wave effect is very weak.Coriolis force influence has the smallest contribution.Finally,the problems of this research and the next work are discussed.