SUMMARY The fast development of Global Positioning System (GPS) technology provides more precise and rapid surveying in geodetic applications than the traditional terrestrial positioning techniques. Therefore, considerable savings on time, labour and cost are achieved by GPS measurements. The geometric height supplied by GPS is ellipsoidal height and it needs to be transformed to orthometric he...

[1] The association between local maxima in the geoid and subduction zones is examined. While it is well known that subduction zones are associated with broad local maxima in the geoid at spherical harmonic degrees 4–9, there is an impressive correlation between back arc geoid maxima at the 5000 km length scale (i.e., spherical harmonic degrees >9) and subduction zones with the exception of the...

Candidate models of the forces which oppose the sinking of slabs are all constrained to produce results consistent with the following observation: relative geoid highs, which one assumes are due to slabs, characteristically occur over subduction zones. Certain models which are otherwise plausible, such as those based on a Newtonian half-space mantle, yield geoid lows instead of highs. This stud...

Introduction Conclusions References Tables Figures Back Close Full Screen / Esc Abstract Introduction Conclusions References Tables Figures Back Close Full Screen / Esc Printer-friendly Version Interactive Discussion EGU 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 produ...

Abstract Recent gravity missions have produced a dramatic improvement in our ability to measure the ocean’s mean dynamic topography (MDT) from space. To fully exploit this oceanic observation, however, we must quantify its error. To establish a baseline, we first assess the error budget for an MDT calculated using a 3rd generation GOCE geoid and the CLS01 mean sea surface (MSS). With these prod...

The development of the Earth Gravitational Model 2008 (EGM2008) model is a significant contribution for modeling the Earth’s gravity and geoid. Recently, it can be confidently used versus geometric models following a simple refinement procedure. Several studies show that, EGM2008 can reach the accuracy of regional or local geoid models after modeling the differences between the GPS-leveling geo...

In this paper we present the concepts and realization of the shallow-layer Shen geoid determination method, which is quite different from the classical geoid modeling methods (Stokes’ method, Molodenskiĭ’s method, etc.), for determining the global or regional geoids. This method takes full advantage of the precise Earth gravity field model EGM2008, digital topographic model DTM2006.0 and global...

[1] Earthquakes are accompanied with mass redistributions and cause changes in gravity field and shape of geoid, an equipotential surface coincident with the mean sea surface. Such coseismic changes were detected by satellite gravimetry after the 2004 Sumatra-Andaman Earthquake, but little has been known on what happens on geoid after the earthquake. Here we report slow postseismic recovery of ...

Satellite altimeters have mapped the marine geoid over virtually all of the world’s oceans. These geoid height measurements may be used to compute free air gravity anomalies in areas where shipboard measurements are scarce. Two-dimensional (2-D) transformations of geoid height to gravity are limited by currently availabie satellite track spacing and usually sacrifice short wavelength resolution...

We adopt Poisson wavelets for regional gravity field recovery using data acquired from various observational techniques; the method combines data of different spatial resolutions and coverage, and various spectral contents and noise levels. For managing the ill-conditioned system, the performances of the zeroand first-order Tikhonov regularization approaches are investigated. Moreover, a direct...