Adjustment of collocated GPS, geoid and orthometric height observations in Greece

dc.contributor.author	Τζιάβος, Ηλίας Ν.	el
dc.contributor.author	Βέργος, Γεώργιος Σ.	el
dc.contributor.author	Γρηγοριάδης, Βασίλειος Ν.	el
dc.contributor.author	Ανδριτσάνος, Βασίλειος Δ.	el
dc.date.accessioned	2015-06-05T20:11:04Z
dc.date.available	2015-06-05T20:11:04Z
dc.date.issued	2015-06-05
dc.identifier.uri	http://hdl.handle.net/11400/15215
dc.rights	Αναφορά Δημιουργού-Μη Εμπορική Χρήση-Όχι Παράγωγα Έργα 3.0 Ηνωμένες Πολιτείες	*
dc.rights.uri	http://creativecommons.org/licenses/by-nc-nd/3.0/us/	*
dc.source	http://link.springer.com/chapter/10.1007%2F978-3-642-20338-1_58	el
dc.subject	Earth (Planet)--Figure
dc.subject	Geopotential height
dc.subject	Global Positioning System
dc.subject	Greece
dc.subject	Γη (Πλανήτης) - Εικόνα
dc.subject	Γεωδυναμικό ύψου
dc.subject	Παγκόσμιο Σύστημα Εντοπισμού Θέσης
dc.subject	Ελλάδα
dc.title	Adjustment of collocated GPS, geoid and orthometric height observations in Greece	en
heal.type	conferenceItem
heal.secondaryTitle	geoid or orthometric height improvement?	en
heal.classification	Environmental sciences
heal.classification	Topography
heal.classification	Περιβαλλοντικές επιστήμες
heal.classification	Τοπογραφία
heal.classificationURI	http://id.loc.gov/authorities/subjects/sh92004048
heal.classificationURI	http://skos.um.es/unescothes/C04078
heal.classificationURI	N/A-Περιβαλλοντικές επιστήμες
heal.classificationURI	N/A-Τοπογραφία
heal.keywordURI	http://id.loc.gov/authorities/subjects/sh85040434
heal.keywordURI	http://id.loc.gov/authorities/subjects/sh2005003633
heal.keywordURI	http://id.loc.gov/authorities/subjects/sh86003934
heal.keywordURI	http://zbw.eu/stw/descriptor/17184-0
heal.identifier.secondary	ISSN: 09399585
heal.identifier.secondary	ISBN: 978-364220337-4
heal.identifier.secondary	DOI: 10.1007/978-3-642-20338-1_58
heal.language	en
heal.access	campus
heal.recordProvider	Σχολή Τεχνολογικών Εφαρμογών. Τμήμα Πολιτικών Μηχανικών Τ.Ε. και Μηχανικών Τοπογραφίας και Γεωπληροφορικής Τ.Ε.. Κατεύθυνση Μηχανικών Τοπογραφίας & Γεωπληροφορικής Τ.Ε.	el
heal.publicationDate	2009-08
heal.bibliographicCitation	Tziavos, I., Vergos, G., Grigoriadis, V. and Andritsanos, V. (2009). Adjustment of collocated GPS, geoid and orthometric height observations in Greece: geoid or orthometric height improvement?. IAG Symposium on Geodesy for Planet Earth, IAG 2009. Chania, Crete, Argentina. 31 August - 4 September 2009. Available from: http://link.springer.com/chapter/10.1007%2F978-3-642-20338-1_58. [Accessed 26/07/2011]	en
heal.abstract	The combined adjustment of GPS/Levelling observations on benchmarks with gravimetric geoid heights has been the focus of extensive research both from the theoretical and practical point of view. Up until today, with few exceptions, the main blame for the inconsistencies/disagreement between these three types of heights has been put to the geoid heights due mainly to their poorer accuracy. With the advent of the new CHAMP- and GRACE-based global geopotential models and the realization of EGM2008 the achievable cumulative geoid accuracy has improved significantly so that its differences to GPS/Levelling heights reach the few cm level. In Greece, GPS observations on BMs are very scarce and cover only small parts, in terms of spatial scale, of the country. Recently, an effort has been carried out to perform new GPS measurements on levelling BMs, so that reliable GPS/Levelling and gravimetric geoid height adjustment studies can be carried out. This resulted in part of North-Western Greece to be covered with reliable observations within an area extending 3° in longitude and 1° in latitude. Therefore, some new potential for the common adjustment of the available geometric, orthometric and geoid heights, using various parametric surfaces to model and interpret their differences, are offered. These are used to come to some conclusions on the accuracy of the various geoid models used (both global geopotential and local gravimetric models), while an extensive outlook is paid to the questionable behaviour of the orthometric heights. The latter is especially important for the Greek territory since the available benchmarks are delaminated in so-called "map-leaflets" and a common adjustment of the entire vertical network has not been carried out so far. It is concluded that even between neighbouring "map-leaflets" large biases in the adjusted GPS/Levelling and gravimetric geoid heights exist, which indicates distortions in the Greek vertical datum as this is realized by the levelling benchmarks. Given that the latter are commonly used for everyday surveying purposes, conclusions and proposals on the determination of adjusted orthometric heights are finally drawn.	en
heal.sponsor	FIG	en
heal.sponsor	ION	en
heal.sponsor	ISPRS	en
heal.fullTextAvailability	true
heal.conferenceName	International Association of Geodesy Symposia	en
heal.conferenceItemType	full paper