本文研究周期大于9天的超低频振动,这类振动与水位长期变化密切相关。海洋水位长期变化是地球自转、气候变异和海洋水量平衡的重要指标,也是大尺度海气互相作用、气候过程、海洋动力学过程和海洋水文因子综合作用的结果。 潮波中的半日潮、全日潮已公认是海洋中典型的低频长波,对其中的长周期分潮族 This paper studies the ultra-low frequency vibration with a period of more than 9 days. Such vibration is closely related to the long-term change of water level. Long-term changes in the ocean’s water level are important indicators of the Earth’s rotation, climate variability and the balance of ocean water. They are also the result of the combined effects of large-scale air-sea interactions, climate processes, ocean dynamics and ocean hydrological factors. Half-day tide in the tide wave, the tide has been recognized as the sea is a typical low-frequency long wave, of which the long-period tidal wave ethnic