海潮次潮波线性拟合方法研究  

Study on Linear Fitting Methods of Secondary Tidal Waves

作　　者：石浩楠 张兴福[1] SHI Haonan;ZHNAG Xingfu(School of Civil and Transportation Engineering,Guangdong University of Technology,University Town,Guangzhou 510006,China)

机构地区：[1]广东工业大学土木与交通工程学院,广州市510006

出　　处：《大地测量与地球动力学》2025年第5期526-531,共6页Journal of Geodesy and Geodynamics

基　　金：国家自然科学基金(42374100)。

摘　　要：高精度和高分辨率海潮模型在时变重力场反演中发挥着重要作用,但发布的海潮模型一般仅给出主潮波分量,次潮波分量拟合系数矩阵需待其他机构发布或自行计算。本文首先根据导纳理论和引潮位,推导了海潮模型次潮波线性拟合的计算公式;然后以EOT11a、EOT20和FES2014b海潮模型为例,分别计算各海潮模型次潮波拟合系数矩阵,以及对应的CHAMP、GRACE和GOCE卫星各1 d的海潮摄动力;最后选择FES2014b海潮模型,反演GRACE-FO 2021-01 120阶次的时变重力场。从不同角度对本文次潮波线性拟合方法的精度和影响进行分析,结果表明,本文计算的3个海潮模型次潮波拟合系数矩阵以及3颗卫星对应的海潮摄动力与ITSG结果的差值均可以忽略;考虑次潮波会提高40阶次以上重力位系数精度,且能降低时变重力场的南北条带误差。本文方法可为自行计算海潮次潮波影响提供参考。High-precision and high-resolution tidal models play a crucial role in the inversion of time-varying gravitational fields,but the published tidal models generally only provide the main tidal components.The fitting coefficient matrix for the secondary tidal components needs to be published by other institutions or calculated independently.This paper first derives the calculation formula for the linear fitting of secondary tidal components in tidal models based on the theory of admittance and tidal potential data.Then,taking the EOT11a,EOT20,and FES2014b tidal models as examples,we calculate the fitting coefficient matrices for the secondary tidal components of each tidal model,as well as the corresponding ocean tide perturbation forces for CHAMP,GRACE,and GOCE satellites for a period of 1 day.Finally,we select the FES2014b tidal model to invert the 120th-order time-varying gravitational field of GRACE-FO for January 2021.The precision and impact of the secondary tidal linear fitting method in this paper are analyzed from different perspectives.The results show that the differences between the fitting coefficient matrices of the three tidal models and the corresponding ocean tide perturbation forces for the three satellites calculated in this paper and the results from the ITSG can be neglected.Considering the secondary tides can improve the precision of gravity potential coefficients above the 40th order and reduce the north-south strip errors in the time-varying gravitational field.The method presented in this paper can provide a reference for independently calculating the impact of secondary tidal components.

关 键 词：海潮模型 次潮波 线性拟合 低轨卫星 海潮摄动加速度 

分 类 号：P223[天文地球—大地测量学与测量工程]