Marine gravity and geoid determination by optimal combination of satellite altimetry and shipborne gravimetry data

Combined satellite altimetry and shipborne gravimetry data processing

“…All the above expressions can be computed sequentially in the same manner as in sequential LSC in the space domain. For detailed derivation of the above equations, see Sideris (1996) and Li and Sideris (1997).…”

“…Numerical tests have demonstrated the potential of satellite altimetry and its efficiency to recover gravity anomalies, geoid heights, and other quantities related to the gravity field (e.g., deflections of the vertical) over open sea areas or in limited sea zones surrounded by land areas, such as the Mediterranean Sea (see, e.g., Arabelos & Tziavos, 1990Olgiati et al, 1995;Hwang, 1989;Basic & Rapp, 1992;Zhang & Sideris, 1994Li & Sideris, 1997;Tziavos et al, 1996). When, besides altimetric data, marine gravity data are available in a specific sea area, these heterogeneous data can be combined to determine gravity field quantities in an optimal way using different methods such as least-squares collocation (LSC), input-output system theory (IOST), and least-squares adjustment in the frequency domain (LSAFD).…”

“…Applications of the method in physical geodesy are discussed by Sansö and , Li and Sideris (1997), and Sideris (1996). The major requirement of the method is that the observation spectra and the power spectral density functions (PSDs) of the observables, the cross-PSDs between different data types, and the noise PSDs should be known (Li & Sideris, 1997).…”

Construction of Least Squares Collocation Models for Single Component and Composite Components of Disturbed Gravity Gradients

“…The frequency domain LSC proposed by Luo [3] can improve the computation speed effectively. Li and Sideris [4] compared the precision of LSC, frequency domain LS and more input/single output theory to recover the local EGM using geoid data obtained by satellite altimetry and gravity anomaly data collected by ships. A new method is proposed by Zhang [5] for the approximation of the EGM, namely, the least squares complex collocation.…”

From Discrete Gravity Survey Data to a High-resolution Gravity Field Representation in the Nordic-Baltic Region

“…Even though there are (quasi)geoid determination methods that can be applied directly without prior gridding of input gravity data (such as Tscherning 1985), many modelling techniques (such as Haagmans, de Min, and Gelderen 1993;Forsberg and Sideris 1993;Li and Sideris 1997;Sjöberg 2003;Ellmann and Vaníček 2007) need a regularly spaced gravity anomaly grid that has to be determined from the scattered survey data that are located from a few hundreds of meters up to a few tens of kilometres apart.…”