在“笛卡尔章动”项目框架内的地球自转和重力场变化
Earth rotation and variations of the gravity field, in the framework of the "Descartes-nutation" project
摘要：
“笛卡尔章动”项目致力于“从理论的角度以及从观测的角度理解岁差章动的下一个小数”。在这个框架内，我们提出了一个建议，以有助于研究（i）的动力学扁率的地球，（ii）的耦合效应的日月强迫，（iii）的地球物理流体的EOP和（iv）章动观测的效果。我们进一步研究地球定向和重力场变化之间的联系。事实上，地球内部的质量分布决定了空间中旋转轴的行为（岁差章动）和地球中的行为（极移），以及地球的旋转速率（或等效的，一天的长度）。这些质量分布可以通过人造卫星在空间进行测量，人造卫星的轨道图提供了地球重力场的确定。然后，地球重力场的时间变化可以与地球定向参数（EOP）的变化（与惯性张量）。目前，利用甚长基线干涉仪（VLBI）获得的空间地球定向测量精度已超过毫角秒级。因此，有必要考虑所有可以提高模型精度的地球物理源。我的博士论文的目标是使用地球重力场测量，以及它的变化，作为一种工具，以改善地球定向建模。我们在这里提出的结果，以及各种建议，以扩大这些调查（数值研究，使用J2地球物理系列，GRACE数据的整合.）。
英文摘要：
The "Descartes-Nutation" Project is devoted to the "understanding of the next decimal of precession-nutation, from the theoretical point of view as well as from the observational point of view". In this framework, we made a proposal in order to contribute to the study of (i) the dynamical flattening of the Earth, (ii) the coupling effects of the lunisolar forcing, (iii) the effect of the geophysical fluids on the EOP and (iv) the Nutation observations. We investigate further the links between Earth Orientation and Gravity Field Variations. Indeed, the masses distributions inside the Earth govern the behaviour of the rotation axis in space (precession-nutation) and in the Earth (polar motion), as well as the Earth rotation rate (or equivalently, length of the day). These distributions of masses can be measured by space owing to artificial satellites, the orbitography of which provides the Earth gravity field determination. Then, the temporal variations of the Earth gravity field can be related to the variations of the Earth Orientation Parameters (EOP) (with the Inertia Tensor). Nowadays, the Earth orientation measurements in space, obtained with Very Long Baseline Interferometry (VLBI), have a precision better than the milliarcsecond level. It is then necessary to consider all the geophysical sources that can improve the models precision. The goal of my PhD Thesis was to use the Earth gravity field measurements, as well as its variations, as a tool to improve the Earth orientation modelisation. We present here the results obtained as well as various proposals to extend these investigations (numerical studies, the use of J2 geophysical series, integration of GRACE data ...).
机构、总结、中文摘要均由AI分析而来，可能存在错误，请以论文正文为准。
