Improvement and extension of ETRS 89 in Latvia and Lithuania based on the NKG 2003 GPS campaign

Abstract

Abstract The present ETRS 89 realisations in Latvia and Lithuania are based on the EUREF‐BAL'92 campaign, which has an estimated accuracy of the same level as the original EUREF 89 campaign (class C). Latvia and Lithuania wish to replace their EUREF‐BAL'92 realisation with an ETRS 89 realisation based on the NKG 2003 GPS campaign. The NKG 2003 GPS campaign was carried out in GPS‐week 1238 (Sept 28th to Oct 4th 2003) under the framework of the Nordic Geodetic Commission (NKG). The campaign included mainly permanent stations in the Nordic and Baltic area as well as Island, Greenland and Svalbard. In Latvia, Lithuania and Denmark also field sites defining ETRS 89 were included. New ETRS 89 coordinates based on the NKG 2003 campaign have been calculated. The campaign resulted in a set of coordinates in ITRF 2000 epoch 2003.75. All stations in Latvia and Lithuania as well as a sub‐set of stations in neighbouring countries were converted to ETRS 89 using the standard procedure described by Boucher and Altamimi....