HR: 08:30h
AN: G41A-03 INVITED    [Abstracts]
TI: The International Terrestrial Reference Frame: Lessons from ITRF2005 and Future Developments
AU: * Altamimi, Z
EM: altamimi@ensg.ign.fr
AF: Zuheir Altamimi, Institut Geographique National ENSG/LAREG 6-8 Avenue Blaise Pascal, Champs-sur-Marne, 77455, France
AB: Up to ITRF2000, global long-term solutions were submitted by the analysis centers of the four techniques (VLBI, SLR, GPS, DORIS) for the ITRF formation. Starting with the ITRF2005, time series of station positions (weekly from satellite techniques and daily from VLBI) and Earth Orientation Parameters (EOPs) are the current ingredients of the ITRF construction. The main advantages of using time series as input data are twofold: (1) to allow monitoring station non-linear motion and all kinds of discontinuities; and (2) to examine the temporal behavior of the frame physical parameters, namely the origin and the scale. The paper starts by a brief introduction of the main features of the combination model used in both the stacking of time series and the combination of long-term global solutions. A particular focus will be given to the main lessons learnt from the ITRF2005, including scale discrepancy between VLBI and SLR solutions, local tie uncertainties, the Z-translation drift of 1.8 mm/yr between ITRF2000 and ITRF2005, consistency of Earth Rotation Parameters and the impact of GPS antenna phase center variation correction. The discussion will be illustrated by the most up to date analysis of the available time series of the 4 techniques.
UR: http://itrf.ensg.ign.fr/ITRF_solutions/2005/ITRF2005.php
DE: 1200 GEODESY AND GRAVITY
DE: 1229 Reference systems
DE: 1239 Earth rotation variations
DE: 1295 Integrations of techniques
SC: Geodesy [G]
MN: 2007 Fall Meeting