Abstract
Levelling increments must be corrected for gravity in order to get proper dynamic or orthometric heights. In Italy, most of the levelling lines have no associated gravity observations. Thus, only levelling increments are available, and corrections were computed only on a subset of the existing lines. However, gravity is densely observed, and thus, predictions of gravity along the levelling lines can be computed. This, in principle, would allow the estimation of corrections along the whole Italian levelling network. Furthermore, global model-derived gravity could be used for the same task (e.g. one could use the EGM2008 global geopotential model to get gravity estimates). To check for the reliability of these procedures, a test has been performed along levelling lines in the western Alps area. Both dynamic and orthometric corrections have been computed in order to finally get geopotential numbers, normal heights and orthometric heights from raw levelling increments. The results proved that reliable results can be obtained using the Italian gravity database, while predictions based on the EGM2008 model led to poorer estimates.
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Albertella A, Barzaghi R, Carrion D, Maggi A (2008) The joint use of gravity data and GPS/levelling undulations in geoid estimation procedures Bollettino di Geodesia e Scienze Affini Anno LXVII:47–57
Barzaghi R, Carrion D (2009) Testing EGM2008 in the central Mediterranean area. Newton's Bulletin, Bureau Gravimétrique International, International Geoid Service Joint Bulletin. IGeS 4:133–143
Barzaghi R, Borghi A, Carrion D, Sona G (2007) Refining the estimate of the Italian quasi-geoid. Bollettino di Geodesia e Scienze Affini Anno LXVI:145–160
Blachut TJ, Chrzanowski A, Saastamoinen JH (1979) Urban surveying and mapping. Springer, New York
Borghi A, Carrion D, Sona G (2007) Validation and fusion of different databases in preparation of high resolution geoid determination. Geophys J Int 171:539–549
Bottoni G, Barzaghi R (1993) Fast collocation. Bull Géodésique 67(2):119–126
Claessens SJ, Featherstone WE, Anjasmara IM, Filmer MS (2009) Is Australian data really validating EGM2008, or is EGM2008 just in/validating Australian data? Newton's Bulletin, Bureau Gravimétrique International, International Geoid Service Joint Bulletin. IGeS 4:207–251
Forsberg R (1994) Terrain effects in geoid computations. Lectures Notes of the International School for the Determination and Use of the Geoid, IGeS, DIIAR, Politecnico di Milano
Gentile G, Maseroli R, Sacerdote F (2011) Studio dell'effetto della gravità su circuiti chiusi della livellazione di alta precisione in presenza di dislivelli molto elevati. Conferenza Nazionale ASITA 15–18 novembre 2011 Proceedings, Parma, Italy, 1151–1158
Heiskanen WA, Moritz H (1967) Physical geodesy. Institute of Physical Geodesy Technical University, Graz
Holmes S, Pavlis N (2008) Earth Gravitational Model 2008 (EGM2008). http://earth-info.nga.mil/GandG/wgs84/gravitymod/egm2008/first_release.html. Accessed 23 October 2012
Ihde J, Adam J, Gurtner W, et al. (1998) The concept of the European Vertical GPS Reference Network (EUVN). EUREF Symposium, Bad Neuenahr-Ahrweiler, Germany, June 10–12 1998
Ihde J, Adam J, Gurtner W, Harsson BG, Sacher M, Schlüter W, Höppelmann G (2000) The height solution of the European Vertical Reference Network (EUVN)
Ihde J, Sacher M, Makinen J (2006) European Vertical Reference System (EVRS) 2007 – a combination of UELN and ECGN. EUREF Symposium, June 2006, Riga (Latvia), http://www.euref.eu/symposia/2006Riga/01-05.pdf. Accessed 23 October 2012
Intesa Stato, Regioni, Gruppo di lavoro Reti plano-altimetriche, (1998) Rete altimetrica fondamentale - Livellazione geometrica di alta precisione – Specifiche tecniche. http://www.centrointerregionale-gis.it/public/A-CapitolLivellaz.rtf. Accessed 23 October 2012
Kenyeres A, Sacher M, Ihde J, Denker H, Marti U (2010) EUVN Densification Action” Final report—EUVN_DA Working Group
Kotsakis C, Katsambalos K, Gianniou M (2009) Evaluation of EGM08 based on GPS and orthometric heights over the Hellenic mainland. Newton's Bulletin, Bureau Gravimétrique International, International Geoid Service Joint Bulletin. IGeS 4:144–163
Roman DR, Saleh J, Wang YM, Childers VA, Li X, Smith DA (2009) EGM08 comparisons with GPS/leveling and limited aerogravity over the United States of America and its Territories. Newton's Bulletin, Bureau Gravimétrique International, International Geoid Service Joint Bulletin. IGeS 4:73–78
Sacher M, Ihde J, Lang H, (1998) Status and results of the Adjustment and Enlargement of the United European Levelling Network 1995 (UELN – 95 ). Report by the EUELN data centre, http://www.bkg.bund.de/nn_164706/geodIS/EVRS/SharedDocs/Downloads/Publications/ResultsOfAdjustmentofUELN95,templateId=raw,property=publicationFile.pdf/ResultsOfAdjustmentofUELN95.pdf. Accessed 23 October 2012
Sacher M, Ihde J, Makinen J (2009) EVRS2007 as realization of European Vertical Reference System. Bulletin of Geodesy and Geomatics, LXVIII,1:35–50
Wenzel, G (1998) - Ultra high degree geopotential models GPM98A, GPM98B and GPM98C to degree 1800 In Proceedings of the Second Continental Workshop on the Geoid in Europe, Budapest, 1998
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Barzaghi, R., Betti, B., Carrion, D. et al. Orthometric correction and normal heights for Italian levelling network: a case study. Appl Geomat 6, 17–25 (2014). https://doi.org/10.1007/s12518-013-0121-9
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DOI: https://doi.org/10.1007/s12518-013-0121-9