IAG-IASPEI 2017

講演情報

Oral

IAG Symposia » G01. Reference frames

[G01-1] International terrestrial reference frame

2017年8月2日(水) 08:30 〜 10:00 Room 502 (Kobe International Conference Center 5F, Room 502)

Chairs: Geoffrey Blewitt (University of Nevada, Reno) , Johannes Boehm (Technische Universität Wien)

09:15 〜 09:30

[G01-1-04] DGFI-TUM analysis and scale investigations of the latest terrestrial reference frame realizations

Mathis Blossfeld, Detlef Angermann, Manuela Seitz (DGFI-TUM, Munich, Germany)

invited

Solutions for the most recent realizations of the International Terrestrial Reference System (ITRS) were computed by the three ITRS Combination Centers (CCs) of the International Earth Rotation and Reference System Service (IERS), namely the IGN in Paris (France), the JPL in Pasadena (US) and the DGFI-TUM in Munich (Germany). Thereby, the solutions of IGN and DGFI-TUM comprise conventional parameters of the ITRS (station coordinates and velocities) at a reference epoch as defined in the IERS Conventions 2010 (Petit et al., 2010). The two solutions are based on identical input data, but differences in the ITRS realization strategies lead to systematic differences between them.
The most important differences are the combination of normal equations systems versus the combination of solutions, the application of non-tidal loading models versus the estimjation of annual and semi-amnnual signals and the different handling of local ties.
Within all ITRS realizations, the scale is realized as a weighted mean scale between SLR (satellite laser ranging) and VLBI (very long baseline interferometry). If the combined scale is compared to the scale realized by both techniques itself, the IGN solutions shows significant differences between SLR and VLBI whereas the DGFI-TUM solution shows a better agreement.
In order to investigate the question whether there is a systematic scale difference between the two solutions or not, the combined solutions of IGN and DGFI-TUM as well as the single-technique solutions of both institutions are analyzed and compared. In addition, the impact of the used local ties on the scale realization is investigated. Moreover, the realization of the origin and the orientation of the two ITRS realizations is compared.