摘要: |
基于港湾假潮振动的基本原理,从渤海、黄海沿岸20个验潮站多年水位自记曲线资料获取假潮参数,并对其做了统计分析,给出了假潮的统计特征,还讨论了假潮形成的初步原因。结果表明,该海域主要港湾假潮出现具有明显的局地性、季节性和年际变化;夏季是大振幅假潮(振幅1)≥80cm)的多发期,冬季基本上不出现;龙口港湾的大振幅假潮最为突出,最大振幅可达293cm;气压和风速、风向突变的良好配合,是发生大振幅假潮的主要原因。 |
关键词: 大振幅假潮,基本特征,假潮参数,主要港湾,渤海、黄海 |
DOI: |
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基金项目:国家自然科学基金资助项目,4967281号;山东省科委计划专项合同资助,96第40号 |
附件 |
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BASIC CHARACTERISTICS OF SEICHES IN THE MAJOR COASTAL EMBAYMENTS OF BOHAI AND YELLOW SEAS |
LI Kun-Ping, CHEN Ze-Shi
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First Institute of Oceanography, State Oceanic Administration
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Abstract: |
The water-level curves from 20 tide-gauge stations along the coasts of Bohai and Yellow Seas were collected. The seiche parameters were selected according to these water-level curves obtained.These data, especially the seiches with relatively large amplitudes, were examined by using statistics and natural period analysis. Basic chracteristics of seiches, such as monthly and annual occurrences, oscillation period, occurrence duration and occurrence time of the peak, were derived. Among these 20 tide-gauge stations, seiches with an amplitude of no less than 50 cm were found at 13 of them. The seiche occurs mostly in June and July. Among the total 147 seiche events, there are 33 sets (or events) with an amplitude greater than 80 cm, and the greatest amplitude is 293 cm. The occurrence of seiches has local and seasonal characters, and interannual variations. The seiches with a large amplitude occur mostly in summer. It basically does not occur in winter. Numbers of the annual occurrence of the seiches with a relatively large amplitudes are not constant and vary randomly in different years. The natural period of fundamental mode calculated by the improvement on Merian s formula coincides well with the period estimated from the curve of observationalwater level except for one of the bays. Observations show that the greatest amplitude of each seiche event occurs mostly during high or low tide.This study shows that the fine coordination of rapid variation of atmospheric pressure, wind speed and direction are main causes of the formation of the seiches with large amplitudes. |
Key words: Large amplitude seiches, Basic characteristics, Seiche parameters, Main bays, Bohai and Yellow Seas |