Centre de documentation
scientifique

Impact of a priori gradients on VLBI-derived terrestrial reference frames / Johannes Böhm (2011) 

Public Titre : Impact of a priori gradients on VLBI-derived terrestrial reference frames Type de document : Article/Communication Auteurs : Johannes Böhm , Auteur ; H. Spicakova, Auteur ; L. Urquhart, Auteur ; et al., Auteur Editeur : Bonn : Universität Bonn Année de publication : 2011 Collection : Schriftenreihe des Instituts für Geodäsie und Geoinformation, ISSN 2699-6685 num. 22 Conférence : EVGA 2011, 20th working meeting of the European VLBI Group for Geodesy and Astrometry 29/03/2011 30/03/2011 Bonn Allemagne OA proceedings Importance : pp 128 - 132 Format : 21 x 30 cm Note générale : Bibliographie Langues : Anglais (eng) Descripteur : [Vedettes matières IGN] Systèmes de référence et réseaux [Termes IGN] analyse diachronique [Termes IGN] données ITGB [Termes IGN] gradient de troposphère [Termes IGN] International Terrestrial Reference Frame Résumé : (Auteur) We compare the influence of two different a priori gradient models on the terrestrial reference frame (TRF) as determined from Very Long Baseline Interferometry (VLBI) observations. One model has been determined by vertical integration over horizontal gradients of refractivity as derived from data of the Goddard Data Assimilation Office (DAO), whereas the second model (APG) has been determined by ray-tracing through monthly mean pressure level re-analysis data of the European Centre for Medium-Range Weather Forecasts. We compare VLBI solutions from 1990.0 to 2011.0 with fixed DAO and APG gradients to a solution with gradients being estimated, and we find better agreement of station coordinates when fixing DAO gradients compared to fixing APG gradients. As a consequence, we recommend that gradients are constrained to DAO gradients, in particular in the early years of VLBI observations (up to about 1990), when the number of stations per session is small and the sky distribution is far from uniform. Later than 1990, the gradients can be constrained loosely and the a priori model is of minor importance. Numéro de notice : C2011-052 Affiliation des auteurs : non IGN Thématique : POSITIONNEMENT Nature : Communication DOI : sans Permalink : https://documentation.ensg.eu/index.php?lvl=notice_display&id=64322

Documents numériques

en open access 14256_evga2011_boehm.pdf Adobe Acrobat PDF