日长和地球引力场参数<em>J</em><sub>2</sub>的长期和长周期变化

日长和地球引力场参数J₂的长期和长周期变化

摘要: 用高精度的现代日长观测结果、近20年的J₂变化的结果和古地球自转结果,讨论了日长和J₂变化的长期和长周期的主要特性,从理论和实测两方面分析了日长和J₂变化的关系及其异同,认为J₂变化的结果在地球动力学研究中的作用应予以重视,综合利用日长和J₂将使这两种资料的潜力得以进一步发挥。

Abstract: The characters of the secular and long-period variations in the length of day and the harmonic coefficient J₂ of geopotential were analyzed based on the recent observational result of the length of day,the result of J₂ variations in the recent twenty years and the ancient astronomical result of the Earth rotation.Then the relation and difference between variations of the length of day and J₂ were discussed according to the theory of the Earth rotation and gravity.Furthermore we stressed the importance of J₂ and the integrated use of the length of day and J₂ for geodynamics.