海潮模型的比较及海潮对地球自转变化的影响  

The Comparison among Ocean Tide Models and the Ocean Tide Effect on the Earth Rotation

作　　者：顾震年[1] 金文敬[1] 王保卫[1] 

机构地区：[1]中国科学院上海天文台,上海200030

出　　处：《天文学进展》1999年第2期126-135,共10页Progress In Astronomy

摘　　要：近年来，由于卫星测高工作的开展，提供了丰富准确的观测资料，产生出许多新的海潮模型。这些海潮模型的相互比较为研究海洋的精细结构、海潮的动力学、地球动力学提供了依据。另一方面，由现代空间技术和新方法来监测地球自转中的高频变化研究领域也有长足的进展。用这些技术可检测出地球自转中的周日和半日变化，其中高频变化的一种重要激发源就是海潮。这是由于引潮位引起海洋的流速和高度的变化，从而激发地球自转的变化一般来说，海潮影响地球自转的高频变化有两种不同的激发机制。地球的惯性张量的变化即质量项，它对应于潮高，而运动项对应于潮流。许多研究表明，从测地技术测定的地球自转中的高频变化和从海潮模型预报的周日和半日潮波变化符合得很好。综合性地评述了近几年国际上海潮对地球自转中周日以下的高频变化影响的最新进展，同时也简要介绍地球自转变化中周日以下的高频变化与海潮模式中的周日和半日变化比较的结果。另外也提出了需解决的一些问题。In recent years, the more precise and rich observational data have been contributed and a number of new ocean tide models have been produced with development of the satellite altimetry technique. The comparison of the different ocean tide models should provide a base to the study of ocean structure, ocean tide dynamics and geodynamics. On the other hand, a remarkable progress of monitoring high-frequency variation in earth rotation from both modern space techniques and new methods has been made. The daily and subdaily variatons of earth rotation are detected with these techniques. The dominant reason of high frequency variation in earth rotation comes from the ocean tide, which produces the variation of both tidal height and velocity of tidal current generated by the tidal potential to excitate a changes in Earth rotation. In general, the oceanic tides induce the earth rotation variation with high-frequency in two different excitation mechnisms: one is the change of the inertia tensor of the Earth , which corresponds the tidal height, the other is the motion term, which corresponds the tidal current. It is shown that the high frequency variation of earth rotation detected from space geodetic techniques agrees well with daily and subdaily variation predicted from the ocean tide model. Recent progress in the study of the influence of ocean tide on earth rotation below daily time scales , which are obtained from the different space observations, is reviewed. Meantime the comparison between observational results and values from theoretical ocean tide models in daily and subdaily terms is introduced.In addition, some unresolved problems on the subject are also outlined.

关 键 词：海潮模型 地球自转 自转变化 海潮 

分 类 号：P183.31[天文地球—天文学] P731.23