Using the Nordic Geodetic Observing System for land uplift studies

摘要

Geodetic observing systems have been planned and developed during the lastdecade. An ideal observing system consists of a network of geodeticobserving stations with several techniques at the same site, publiclyaccessible databases, and as a product delivers data time series,combination of techniques or some other results obtained from the data sets.Globally, there is the International Association of Geodesy (IAG) GlobalGeodetic Observing System (GGOS), and there are ongoing attempts to createalso regional observing systems. In this paper we introduce one regionalsystem, the Nordic Geodetic Observing System (NGOS) hosted by the NordicGeodetic Commission (NKG).Data availability and accessibility are one of the major issues today. Wediscuss in general data-related topics, and introduce a pilot databaseproject of NGOS. As a demonstration of the use of such a database, we applyit for postglacial rebound studies in the Fennoscandian area. We compareland uplift values from three techniques, GNSS, tide gauges and absolutegravity, with the Nordic Geodetic Commission NKG2005LU land uplift model forFennoscandia. The purpose is to evaluate the data obtained from differenttechniques and different sources and get the most reliable values for theuplift using publicly available data.The primary aim of observing systems will be to produce data and otherproducts needed by multidisciplinary projects, such as Upper Mantle Dynamicsand Quaternary Climate in Cratonic Areas (DynaQlim) or the European PlateObserving System (EPOS), but their needs may currently exceed the scope ofan existing observing system. We discuss what requirements the projects poseto observing systems and their development. To make comparisons betweendifferent studies possible and reliable, the researcher should document whatthey have in detail, either in appendixes, supplementary material or someother available format.