Abstract
Abstract This paper aims to present a new estimate for the vertical offset between both Brazilian vertical data: DVB-I, in Imbituba-SC, and DVB-S, in Santana-AP. Brazilian Fundamental Altimetric Network (BFAN) currently has over 69000 stations with known normal-orthometric heights; 472 of these stations are connected to a tide gauge located in Santana-AP, at the North portion of Brazil, and the other ones are connected to a tide gauge located in Imbituba-SC, at the South portion of Brazil and considered Brazilian's main vertical reference. The vertical offset estimate is based on comparisons between reference and calculated normal-orthometric heights from values obtained arising of discrete GNSS observations on BFAN benchmarks, normal-geoid heights calculated from GGM XGM2016, which has proven to better model this variable in the region, and through a relative approach for heights determination, which has also proven to be the best way to handling the appropriate variables. As a result, a vertical offset of 1.32 m ± 0.07 m was obtained, which is coherent to previous studies performed in the same intent. This study up-comes as a new validation of the employed methodology itself, by achieving satisfactory results through independent manipulation even with low quality of input data for the region.
Highlights
Mueller (1985) defines that the purpose of a reference frame is to provide the means to materialize a reference system so that it can be used for the quantitative description of positions and motions on the earth, or of celestial bodies, including the earth, in space
For the particular case of Brazilian Fundamental Altimetric Network (BFAN), one of the networks that integrate the Brazilian Geodetic System (BGS) and under responsibility of Brazilian Institute of Geography and Statistics (IBGE), these realizations are provided in terms of benchmarks distributed heterogeneously over the entire Brazilian territory and linked to a national reference system
In this paper, we intend to expose the methods applied by Nicacio (2017) for providing a new estimate for this offset, based on comparisons between known normal-orthometric heights and values obtained from discrete GNSS observations on specific BFAN benchmarks, normal-geoid heights calculated from Global Geopotential Models (GGMs) XGM2016, which has been proven to better model this variable in the region (Nicacio, 2017), and through a relative approach for heights determination, which has been proven to be the best way to handling appropriate variables (Nicacio, 2017)
Summary
Mueller (1985) defines that the purpose of a reference frame is to provide the means to materialize a reference system so that it can be used for the quantitative description of positions and motions on the earth (terrestrial frames), or of celestial bodies, including the earth, in space (celestial frames). For the particular case of Brazilian Fundamental Altimetric Network (BFAN), one of the networks that integrate the Brazilian Geodetic System (BGS) and under responsibility of Brazilian Institute of Geography and Statistics (IBGE), these realizations are provided in terms of benchmarks distributed heterogeneously over the entire Brazilian territory and linked to a national reference system. These benchmarks carry out normal-orthometric heights information, which are heights arising from leveling operations, only corrected from the non-parallelism of gravity field equipotential surfaces (Luz, 2008). Further information about BFAN/BGS can be viewed in Luz (2008) and Nicacio (2017)
Sign-in/Register to view highlights & summary Sign-in/Register to access full text options 
Talk to us
Join us for a 30 min session where you can share your feedback and ask us any queries you have
Schedule a callDisclaimer: All third-party content on this website/platform is and will remain the property of their respective owners and is provided on "as is" basis without any warranties, express or implied. Use of third-party content does not indicate any affiliation, sponsorship with or endorsement by them. Any references to third-party content is to identify the corresponding services and shall be considered fair use under The CopyrightLaw.
