Análise da Evolução Temporal do Datum Vertical Brasileiro de Imbituba

Abstract

Nowadays, the most central themes of Geodesy are linked to the provision of a unique  Global Reference System, to which can be tied of unique form and with sufficient accuracy the geometrical and physical global changes. The Global Geodetic Reference Frame aims at better structuring Earth Observation Systems currently with prospects of the global changes determination at the level of one part per billion, considering several geometric and physical parameters. In this context, it is intended that the International Height Reference Frame, realization of the International Height Reference System, has an overall consistency of at least one centimeter in its realization and space/temporal control in the order of millimeter per year. Considering these aspects, it was analyzed the temporal evolution of the Imbituba Brazilian Vertical Datum utilizing tide gauge data from the sea level obtained from: Permanent Service for Mean Sea Level (1948 to 1968), University of Hawaii Sea Level Center (2001 to 2007) and Permanent Tide Gauge Network for Geodesy (2006 to 2016), and data from different altimetry missions from 1991 to 2015 obtained from the database of the Deutsches Geodätisches Forschungsinstitut. As like as, data obtained from GNSS continuous positioning of period from 2007 to 2016 from Brazilian GNSS Network for Continuous Monitoring, which were used to modeling the local movements of the crust. The results allowed discriminating the crust movements in relation to the sea  level. To achieve it, the trend of sea level variation evidenced by the tide gauge was used, as well as the variation of the vertical component obtained with the GNSS processing and the Sea Surface Height obtained from the satellite altimetry data. level.