GOCE orbit analysis

Long-wavelength gravity field determination using the acceleration approach

verfasst von

O. Baur, T. Reubelt, M. Weigelt, M. Roth, N. Sneeuw

Abstract

The restricted sensitivity of the Gravity field and steady-state Ocean Circulation Explorer (GOCE) gradiometer instrument requires satellite gravity gradiometry to be supplemented by orbit analysis in order to resolve long-wavelength features of the geopotential. For the hitherto published releases of the GOCE time-wise (TIM) and GOCE space-wise gravity field series - two of the official ESA products - the energy conservation method has been adopted to exploit GPS-based satellite-to-satellite tracking information. On the other hand, gravity field recovery from data collected by the CHAllenging Mini-satellite Payload (CHAMP) satellite showed the energy conservation principle to be a sub-optimal choice. For this reason, we propose to estimate the low-frequency part of the gravity field by the point-wise solution of Newton's equation of motion, also known as the acceleration approach. This approach balances the gravitational vector with satellite accelerations, and hence is characterized by (second-order) numerical differentiation of the kinematic orbit. In order to apply the method to GOCE, we present tailored processing strategies with regard to low-pass filtering, variance-covariance information handling, and robust parameter estimation. By comparison of our GIWF solutions (initials GI for "Geodätisches Institut" and IWF for "Institut für WeltraumForschung") and the GOCE-TIM estimates with a state-of-the-art gravity field solution derived from GRACE (Gravity Recovery And Climate Experiment), we conclude that the acceleration approach is better suited for GOCE-only gravity field determination as opposed to the energy conservation method.

Organisationseinheit(en)

Institut für Erdmessung

Externe Organisation(en)

Austrian Academy of Sciences
Universität Stuttgart

Typ

Artikel

Journal

Advances in space research

Band

50

Seiten

385-396

Anzahl der Seiten

12

ISSN

0273-1177

Publikationsdatum

01.08.2012

Publikationsstatus

Veröffentlicht

Peer-reviewed

Ja

ASJC Scopus Sachgebiete

Luft- und Raumfahrttechnik, Astronomie und Astrophysik, Geophysik, Atmosphärenwissenschaften, Astronomie und Planetologie, Allgemeine Erdkunde und Planetologie

Ziele für nachhaltige Entwicklung

SDG 7 – Erschwingliche und saubere Energie, SDG 13 – Klimaschutzmaßnahmen

Elektronische Version(en)

https://doi.org/10.1016/j.asr.2012.04.022 (Zugang: Unbekannt)