地球定向参数高精度预报方法研究

Researches on High Accuracy Prediction Methods of Earth Orientation Parameters

地球自转表征了固体地球与大气、海洋、地幔和地核在各种时空尺度上的耦合过程，地球的自转运动可以用地球定向参数（EOP）（主要包括极移两个分量和日长变化）来描述．EOP是地球参考系和天球参考系之间的转换参数，在深空探测、卫星精密定轨和天文地球动力学研究等领域都有重要应用．由于复杂的数据处理过程，空间大地测量技术获取的EOP存在几天至两个星期的延迟．现代空间导航等对EOP预报值的需求日益增长，使得寻求高精度EOP预报方法成为一项需要深入研究的课题．本文主要从以下几个方面展开，探讨提高EOP预报精度的方法．

The Earth rotation reflects the coupling process among the solid Earth, atmosphere, oceans, mantle, and core of the Earth on multiple spatial and temporal scales. The Earth rotation can be described by the Earth＇s orientation parameters, which are abbreviated as EOP （mainly including two polar motion components PMx and PMy, and variation in the length of day ALOD）. The EOP is crucial in the transformation between the terrestrial and celestial reference systems, and has important applications in many areas such as the deep space exploration, satellite precise orbit determination, and astrogeodynamics. However, the EOP products obtained by the space geodetic technologies generally delay by several days to two weeks. The growing demands for modern space navigation make high-accuracy EOP prediction be a worthy topic. This thesis is composed of the following three aspects, for the purpose of improving the EOP forecast accuracy.