 |
| Titel |
Evaluation of Contemporary Geocenter Motion Solutions |
| VerfasserIn |
Tzu-Yuan Chung, Chung-Yen Kuo, C. K. Shum, Jun-Yi Guo, Hyongki Lee, Kai-Chien Cheng |
| Konferenz |
EGU General Assembly 2010
|
| Medientyp |
Artikel
|
| Sprache |
Englisch
|
| Digitales Dokument |
PDF |
| Erschienen |
In: GRA - Volume 12 (2010) |
| Datensatznummer |
250038818
|
|
|
|
|
|
| Zusammenfassung |
| Geocenter motion, traditionally defined as the motion of the center of mass (CM)
relative to the center of figure (CF) and is represented as the changes of degree one
spherical harmonics, is widely concurred as resulting from mass redistribution
within the Earth system. Accurate geocenter motion estimates are important for the
improved realization of the International Terrestrial Reference Frame (ITRF), are
critical components of Earth’s surface mass load, and have been postulated to be
important to quantify secularly or long period mass changes of the Earth for example, to
correctly interpretation mass signals observed by GRACE. Previous studies have used
different methods for estimating geocneter motion including the use of satellite
laser ranging (SLR of Lageos-1/-2), ground-based GPS, GPS tracking onboard of
LEOs (GRACE satellites), DORIS, and hydrologic and ocean circulation models
(GLDAS and ECCO) and loading models in combination with GRACE data. It has
been stated that it is possible to estimate geocenter motion with an accuracy of
2–3 mm in seasonal signal amplitude and 20 degrees in phase. In particular, the
z-component of the geocenter is much less well determined with the exception of SLR. The
estimated geocenter motion solutions concentrated on seasonal variations. In this
contribution, we provide an evaluation of contemporary geocenter solutions using
various methods including our solution obtained by combining GRACE and other
measurements, and the impact of accuracy of C20 change on the geocenter motion solution. |
|
|
|
|
|
|