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题名	固体潮和卫星重力场恢复中的负荷问题及其应用研究
作者	周江存
学位类别	博士
答辩日期	2008-12
授予单位	中国科学院测量与地球物理研究所
授予地点	武汉
导师	孙和平
关键词	固体潮 地表质量负荷 重力潮汐改正模型 负荷数值模型 EOFs GRACE卫星重力 水重力导纳
学位专业	固体地球物理
中文摘要	L研究表明，精密的固体潮观测可以为地表和空间大地测量提供参考，也是研究地球深内部构造的重要手段。因此固体潮是大地测量和地球物理学中一项重要的研究内容。重力测量是确定地球形状和外部重力场的最基本的任务，因此扣除由日、月等天体的引力导致的重力潮汐显得尤为重要，不仅如此，在GRACE等卫星重力测量中，为得到高精度的地球重力场模型，潮汐也是需要精密扣除的。在目前高精度的全球定位系统（GPS）测量中，为了研究地壳和板块运动，需要扣除地表的潮汐形变。倾斜和应变固体潮的观测在地壳运动变形和地震研究中也有着非常重要的作用，地表质量的负荷作用使得地球发生变形，产生物质的时空变化，它所导致的地球物理场的变化在目前的技术条件下也是可观测的。为了深入研究和解释观测到的各种物理量的变化，需要对固体潮和地表质量负荷进行深入地研究，并从观测值中扣除这些效应，从而获得准确的关于地壳运动与地球深内部构造的信息。 本文系统分析了固体潮和卫星重力测量中的地表质量负荷的影响问题，主要研究的内容和成果如下： 1、详细介绍了固体潮的引潮位理论以及各种理论固体潮的计算方法，推导了由于地球自转变化导致的重力、位移、倾斜和应变等变化的计算公式； 2、详细介绍了地球在表面质量负荷作用下的形变问题，着重讨论了负荷效应的计算，特别是球谐计算方法中重力负荷引力项的计算问题的讨论，详细推导了在频率域固体潮观测的负荷改正公式，讨论了改正中不同地区和不同类型潮波的相位问题； 3、计算了固体潮观测中的负荷效应，包括重力、位移、倾斜和应变观测。对于重力，讨论了海潮负荷对重力的影响，包括长周期、周日和半日波重力固体潮的海潮负荷改正。利用固体潮理论模型和海潮负荷构建了中国大陆精密重力潮汐改正模型，该模型的精度优于0.510-8 ms-2。分析讨论了大气、非潮汐海洋和陆地水负荷对重力季节性变化的影响，在它们的共同作用下产生的重力的季节性变化达到1010-8 ms-2量级。对于位移，分析计算了全球海潮以及近海潮汐对GPS观测点位和基线的影响，在沿海地区对点位的影响达到cm量级，而对基线的影响小于1 cm。利用中国IGS站的由GPS观测获得的垂直位移序列分析了垂直位移的季节性变化，该变化达到cm的量级。同时计算了大气、非潮汐海洋和陆地水的负荷效应，它们的综合影响也达到cm的量级。对于倾斜，对佘山台的倾斜固体潮观测实施了海潮负荷改正，观测残差中存在明显的海潮负荷信号；对于应变，对黄石台应变固体潮观测实施了海潮负荷改正，改正后的潮汐参数变化明显，但与理论值仍有很大差异。 4、讨论了固体潮和地表质量负荷对GRACE卫星重力的影响，计算了固体潮对GRACE重力卫星的摄动影响和海潮对大地水准面的影响，以及由于卫星重力测量对地面点低采样导致的月均值中的aliasing效应。计算了固体潮和海潮模型误差对卫星重力的影响。分析了陆地水变化对卫星重力测量的影响，计算了其影响的阶方差。对由GRACE获得的地表重力变化和地表重力测量获得的变化以及由模型计算的结果进行了比较，一方面用重力测量来验证水储量变化模型的准确性，另一方面用地表重力测量标定GRACE结果，也为水储量变化模型的局部特征提供了很好的约束。 5、介绍了利用GRACE重力测量反演全球水储量变化的方法，包括高斯平滑和去相关处理技术。用EOFs分析方法对GRACE反演的结果进行了分析。通过水重力导纳对用重力观测资料反演局部水储量的变化进行了初步的试验，获得了台站附近水储量的变化，并与模型给出的结果进行了比较，显示出较好的一致性
英文摘要	The previous researches show that accurate surveying of the Earth’s tides effectively provides ground- and space-based geodesy with reference and is one reliable technique for studying the structure of the Earth’s deep interior. Hence, the investigation on the Earth’s tides is an important task in geodesy and geophysics. Gravity measurement is the fundamental task to determine the Earth’s shape and exterior gravity field. Therefore correcting the tides, which are induced by the attractions of the Sun and Moon, is of great importance. Besides, tides are necessary to be accurately corrected in satellite gravimetry such as GRACE. In order to study crust and plate motion, the tidal deformation should be deducted from the high precision GPS surveying. Meanwhile, the tilt and strain play an important role in crustal deformation and seismology. Surface mass loading deforms the Earth and induce temporal and spatial variations of mass in the Earth. The variations of geophysical fields of the Earth induced by loading are measurable with present techniques. In order to deeply investigate and interpret the observed variations of these geophysical fields, it is necessary to study the Earth’s tides and surface mass loading and to deduct them from the observations and to obtain the accurate information about crustal movement and the structure of the Earth’s deep interior. In this paper, the problems of surface mass loading effect on the Earth’s tides and satellite gravity field recovery are comprehensively analyzed. The main materials at present are 1． The tidal generating theory of the Earth’s tides and the computation methods of different kinds of tides are introduced and the formulas of gravity and displacement and tilt and strain induced by polar motion are derived. 2． The problem of the deformation of the Earth due to surface mass loading is introduced briefly. The computation methods of loading effects are discussed. Especially the computation of attraction item of gravity in spherical harmonic method is emphasized. In frequency band, the formulas of ocean tide loading correction to Earth tides are derived briefly. The problem of phase correction of different constituents over different areas is emphasized. 3． The loading effects in Earth’s tides observations including gravity and displacement and tilt and strain are analyzed. For gravity, the ocean tide loading effects are discussed, which involves loading corrections for long-term and diurnal and semidiurnal constituents. Based on the theoretical Earth’s tides models and the ocean tide loading model, the correction model of tidal gravity in Chinese continent is constructed. The precision of the model is better than 0.510-8 ms-2. The loading effects of atmosphere and non-tidal ocean and land water on seasonal variations of gravity are investigated, the magnitude of the effects of these three kind of mass loading on gravity is of 1010-8 ms-2. For displacement, the effects of ocean tide loading on position and baseline are calculated. The effects are of centimeter in magnitude in costal areas and are less than one centimeter on baseline. The seasonal variations of vertical displacements are simultaneously analyzed by GPS data and atmosphere and non-tidal ocean and landwater data at some IGS stations in China. The variations are of centimeter in magnitude. For the tilt, the ocean tide loading correction on tilt observations at Sheshan station is carried out. The residuals are obviously comprised of ocean tide loading effects. For the strain, the ocean tide loading correction on strain observations at Huangshi station is carried out. The corrected tidal parameters are obviously changed and are still different from the theoretical ones. 4． The effects of the Earth’s tides and surface mass loading on GRACE satellite gravity field recovery are discussed. The perturbations of the orbits of the GRACE satellites due to Earth’s tides and the variations of geoid due to ocean tide loading are calculated. Moreover, the aliasing effect on monthly mean values due to low sample rate of the satellites is estimated. At the same time the effects of the errors of the Earth’s tides model and the ocean tide model as well as the variations of landwater storage on satellite gravity field recovery are also estimated. The degree variances are calculated. The comparison of gravity variations obtained by ground- and space-based observations and the ones obtained by water storage models is carried out. On one hand, the gravity observations are used to validate the reliability of the models. On the other hand, the ground-based observations are used to calibrate the space-based observations and to constrain the local water storage models. 5． The method of inversion of water storage variations from GRACE gravimetry is introduced, which involves Gaussian smoothing and de-correlation technique. The inversed water storage changes from GRACE gravity are analyzed by EOFs technique. The primary tests on inversion of local water storage changes from ground-based gravity observations are carried out through the water-gravity admittance. The inversed water storage changes are well comparative with the model predictions.
语种	中文
公开日期	2013-01-17
内容类型	学位论文
源URL	[http://ir.whigg.ac.cn//handle/342008/3688]
专题	测量与地球物理研究所_学生论文_学位论文
推荐引用方式 GB/T 7714	周江存. 固体潮和卫星重力场恢复中的负荷问题及其应用研究[D]. 武汉. 中国科学院测量与地球物理研究所. 2008.

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