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REFINING OF CENTIMETER-PRECISE LOCAL QUASI-GEOID
区域厘米级似大地水准面的精化

邓标,洪绍明,宋雷
大地测量与地球动力学 , 2009,
Abstract: From the determination of the data of quasi-geoid,the paper mainly explores the techniques for local quasi-geoid refining.As applying them to engineering projects the accuracy of cedimeter level can be reached.
Application of Geoid Anomalies to the Tectonic Research in the East Asian Continental Margin Application of Geoid Anomalies to the Tectonic Research in the East Asian Continental Margin  [PDF]
WU Xiaoyang,XING Junhui,LI Chaoyang,LIU Xinzhe,YANG Kai,CHEN Hongyan,GONG Wei
- , 2018,
Abstract: In this paper, we calculated multi-scale residual geoid anomalies with the method of geoid separation processing, according to EGM2008 ultra-high order gravity field model, remove-restore technique and Stokes integral. The East Asian continental margin was selected as the study area. The residual geoid anomalies have been calculated by programming. On the basis of residual geoid anomalies at various orders, the interlayer geoid anomalies at different depths were calculated to depict the spatial distribution characteristics of the residual geoid. Finally, we conducted a detailed geophysical interpretation for the study area according to the geoid anomalies in combination with other geophysical datasets. Four conclusions can be outlined as follows: 1) it is impracticable that geoid anomalies are used in the interpretation of the shallow objects due to the influence of the terrain; 2) the anomalies of residual geoid can reflect the intensity of small-scale mantle convection in the asthenosphere; 3) the interlayer geoid anomalies can reflect the magmatic activities associated with the mantle convection and mantle plume in different scales; 4) the study of the geoid may provide an approach for the research of the subduction zone, mantle convection and mantle plume
地面1.35厘米辐射计系统实时遥感分层水汽总量的实验研究  [PDF]
黄润恒 Huang Runheng,魏重 Wei Chong
大气科学 , 1986, DOI: 10.3878/j.issn.1006-9895.1986.03.02
Abstract: 本文给出了利用配有微机测控单元的地面1.35厘米辐射计实时遥感水汽分层总量的原理和技术,介绍了辐射计的稳定性和自然定标方法.1984年夏季的观测结果表明,辐射计测得的分层总量与相应的探空值的均方根偏差为0.20—0.25克/厘米~2,两者的相关系数达90%以上.
Determination of a Gravimetric Geoid Solution for Andalusia (South Spain)  [PDF]
Francisco Manzano, Victor Corchete, Mimoun Chourak, Gil Manzano
Engineering (ENG) , 2010, DOI: 10.4236/eng.2010.23022
Abstract: The orthometric heights can be obtained without levelling by means of the ellipsoidal and geoidal heights. For engineering purposes, these orthometric heights must be determined with high accuracy. For this reason, the determination of a high-resolution geoid is necessary. In Andalusia (South Spain) a new geopotential model (EIGEN-GL04C) has been available since the publication of a more recent regional geoid. As a consequence, these new data bring about improvements that ought to be included in a new regional geoid of Andalusia. With this aim in mind, a new gravimetric geoid determination has been carried out, in which these new data have been included. Thus, a new geoid is provided as a data grid distributed for the South Spain area from 36 to 39 degrees of latitude and –7 to –1 degrees of longitude (extending to 3 × 6 degrees), in a 120 × 240 regular grid with a mesh size of 1.5’ × 1.5’ and 28800 points in the GRS80 reference system. This calculated geoid and previous geoids are compared to the geoid undulations obtained for 262 GPS/levelling points, distributed within the study area. The new geoid shows an improvement in accuracy and reliability, fitting the geoidal heights determined for these GPS-levelling points better than any previous geoid.
vDetermination of geoid by GPS/Gravity data
应用GPS/重力数据确定(似)大地水准面

LI Fei,YUE Jian-Li,ZHANG Li-Ming,School of Geodesy,Geomatics of Wuhan University,Wuhan,China Institute of Geodesy,Geophysics,Chinese Academy of Sciences,Wuhan,China Graduate School of the Chinese Academy of Sciences,Beijing,China,
李斐
,岳建利,张利明

地球物理学报 , 2005,
Abstract: As an application and test of GPS/Gravity boundary value problem, a local geoid located on N area is determined, by using 702 GPS/Gravity data for calculation and 52 GPS/Leveling for matching and checking. The accuracy analyses by matching with GPS/Leveling data and by direct correction to system difference show that the determination of local geoid computed by GPS/Gravity data and method of GPS/Gravity BVP achieved centimeter accuracy.
用1.35厘米波长地面微波辐射计探测大气中水汽总量及分布  [PDF]
魏重 Wei Chong,薛永康 Xue Yongkang,朱晓明 Zhu Xiaoming,等 et a
大气科学 , 1984, DOI: 10.3878/j.issn.1006-9895.1984.04.08
Abstract: 用1.35厘米波长地面微波辐射计进行了全年四个季节的观测.采用蒙特卡洛法对资料进行了反演.七十多份资料的统计结果表明:水汽总量的相对误差为5.3%,低层水汽廓线(750毫巴以下)的相对误差在20%以下,对水汽总量及廓线随时间的演变与天气背景的关系亦作了初步分析.
An oceanographer’s guide to GOCE and the geoid  [PDF]
C. W. Hughes,R. J. Bingham
Ocean Science Discussions (OSD) , 2006,
Abstract: A review is given of the geodetic concepts necessary for oceanographers to make use of satellite gravity data to define the geoid, and to interpret the resulting product. The geoid is defined, with particular attention to subtleties related to the representation of the permanent tide, and the way in which the geoid is represented in ocean models. The usual spherical harmonic description of the gravitational field is described, together with the concepts required to calculate a geoid from the spherical harmonic coefficients. A brief description is given of the measurement system in the GOCE satellite mission, scheduled for launch shortly, followed by a description of a reference ellipsoid with respect to which the geoid may be calculated. Finally, a recipe is given for calculation of the geoid relative to any chosen ellipsoid, given a set of spherical harmonic coefficients and defining constants.
Comments to X. Li and Y. M. Wang (2011) Comparisons of geoid models over Alaska computed with different Stokes' kernel modifications, JGS 1(2): 136-142
L. E. Sj berg
Journal of Geodetic Science , 2012, DOI: 10.2478/v10156-011-0022-y
Abstract: Li and Wang recently compared geoid determination by various gravimetric methods for modifying Stokes' formula vs. using GPS/levelling geoid heights as a reference model. Possible large systematic errors in the differences of gravimetric and GPS/levelling geoid models deteriorate the results and conclusions. Moreover, spectral combination, the only stochastic method in the study, was applied in an unrealistic way.
An Oceanographer's Guide to GOCE and the Geoid  [PDF]
C. W. Hughes,R. J. Bingham
Ocean Science (OS) & Discussions (OSD) , 2008,
Abstract: A review is given of the geodetic concepts necessary for oceanographers to make use of satellite gravity data to define the geoid, and to interpret the resulting product. The geoid is defined, with particular attention to subtleties related to the representation of the permanent tide, and the way in which the geoid is represented in ocean models. The usual spherical harmonic description of the gravitational field is described, together with the concepts required to calculate a geoid from the spherical harmonic coefficients. A brief description is given of the measurement system in the GOCE satellite mission, scheduled for launch shortly. Finally, a recipe is given for calculation of the ocean dynamic topography, given a map of sea surface height above a reference ellipsoid, a set of spherical harmonic coefficients for the gravitational field, and defining constants.
Geophysical applicability of atomic clocks: direct continental geoid mapping  [PDF]
Ruxandra Bondarescu,Mihai Bondarescu,Gy?rgy Hetényi,Lapo Boschi,Philippe Jetzer,Jayashree Balakrishna
Physics , 2012, DOI: 10.1111/j.1365-246X.2012.05636.x
Abstract: The geoid is the true physical figure of the Earth, a particular equipotential surface of the gravity field of the Earth that accounts for the effect of all subsurface density variations. Its shape approximates best (in the sense of least squares) the mean level of oceans, but the geoid is more difficult to determine over continents. Satellite missions carry out distance measurements and derive the gravity field to provide geoid maps over the entire globe. However, they require calibration and extensive computations including integration, which is a non-unique operation. Here we propose a direct method and a new tool that directly measures geopotential differences on continents using atomic clocks. General Relativity Theory predicts constant clock rate at sea level, and faster (resp. slower) clock rate above (resp. below) sea level. The technology of atomic clocks is on the doorstep of reaching an accuracy level in clock rate that is equivalent to 1 cm in determining equipotential surface (including geoid) height. We discuss the value and future applicability of such measurements including direct geoid mapping on continents, and joint gravity and geopotential surveying to invert for subsurface density anomalies. Our synthetic calculations show that the geoid perturbation caused by a 1.5 km radius sphere with 20% density anomaly buried at 2 km depth in the crust of the Earth is already detectable by atomic clocks of achievable accuracy. Therefore atomic clock geopotential surveys, used together with relative gravity data to benefit from their different depth sensitivities, can become a useful tool in mapping density anomalies within the Earth.
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