Assessment of Earth Gravity Field Models in the Medium to High Frequency Spectrum Based on GRACE and GOCE Dynamic Orbit Analysis

Geosciences

Dimitrios Tsoulis¹  ThomasD. Papanikolaou² 

[1] Department of Geodesy and Surveying, Aristotle University of Thessaloniki, 54124 Thessaloniki, Greece;Geoscience Australia, Cnr Jerrabomberra Ave and Hindmarsh Drive, Symonston, ACT 2609, Australia;

关键词: dynamic orbit determination;    gravity field models;    satellite gravity missions;    inter-satellite ranging;   

DOI  :  10.3390/geosciences8120441

来源: DOAJ

【 摘 要 】

An analysis of current static and time-variable gravity field models is presented focusing on the medium to high frequencies of the geopotential as expressed by the spherical harmonic coefficients. A validation scheme of the gravity field models is implemented based on dynamic orbit determination that is applied in a degree-wise cumulative sense of the individual spherical harmonics. The approach is applied to real data of the Gravity Field and Steady-State Ocean Circulation (GOCE) and Gravity Recovery and Climate Experiment (GRACE) satellite missions, as well as to GRACE inter-satellite K-band ranging (KBR) data. Since the proposed scheme aims at capturing gravitational discrepancies, we consider a few deterministic empirical parameters in order to avoid absorbing part of the gravity signal that may be included in the monitored orbit residuals. The present contribution aims at a band-limited analysis for identifying characteristic degree ranges and thresholds of the various GRACE- and GOCE-based gravity field models. The degree range 100⁻180 is investigated based on the degree-wise cumulative approach. The identified degree thresholds have values of 130 and 160 based on the GRACE KBR data and the GOCE orbit analysis, respectively.

【 授权许可】

Unknown