Contribution of Non-Tidal Oceanic Mass Variations to Polar Motion Determined from Space Geodesy and Ocean Data
Contribution of Non-Tidal Oceanic Mass Variations to Polar Motion Determined from Space Geodesy and Ocean Data
复制标题
根据空间大地测量学和海洋数据确定的非潮汐海洋质量变化对极地运动的贡献
DOI：
10.1007/978-3-540-85426-5_53
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发表时间：
2009
期刊：
影响因子：
--
通讯作者：
Seitz F.
中科院分区：
文献类型：
--
作者：
Göttl F;Seitz F.
为了评估非潮汐海洋质量变化对极移的贡献，赤道海洋激励函数是根据空间大地测量技术和海洋数据的组合确定的。卫星测高提供有关由海水质量和体积变化引起的海平面异常 (SLA) 的准确信息。由于地球自转仅受质量变化的影响，因此必须从观测中减少体积（空间）效应，以便推断海洋对地球自转的贡献。将减少的 SLA 产生的海洋极移激励与海洋模型的相应结果进行比较。添加了洋流、大气和水文效应的贡献，以便通过独立的大地测量观测来验证高度测量的海洋激发，这些观测反映了地球系统中多种地球物理过程的整体效应。这需要对组合数据集的准确性和一致性进行调查。研究表明，大气、海洋和水文激励的纯模型组合比包含测高激励的组合更符合大地测量观测结果。可能的原因可能是 SLA 空间还原中的错误和/或通过数值海洋模型补偿大气数据中的错误模式
In order to assess the contribution of non-tidal oceanic mass changes to polar motion, equatorial oceanic excitation functions are determined from combinations of space geodetic techniques and ocean data. Satellite altimetry provides accurate information on sea level anomalies (SLA) which are caused by mass and volume changes of seawater. Since Earth rotation is solely affected by mass variations the volume (steric) effect has to be reduced from the observations in order to infer oceanic contributions to Earth rotation. Oceanic polar motion excitations from reduced SLA are compared with respective results from ocean models. Contributions of ocean currents, atmospheric and hydrological effects are added in order to validate the oceanic excitations from altimetry with independent geodetic observations which reflect the integral effect of a multitude of geophysical processes in the Earth system. This requires an investigation of accuracy and consistency of the combined data sets. The study reveals that model-only combinations of atmospheric, oceanic and hydrological excitations agree better with geodetic observations than combinations which include excitations from altimetry. Possible reasons could be errors in the steric reduction of SLA and/or the compensation of erroneous patterns in atmosphere data by numerical ocean models
影响因子：
3.9
作者：
Chen, JL;Wilson, CR;Tapley, BD
通讯作者：
Tapley, BD