Povilas Viskontas

Lietuvos gravimetrinio tinklo charakteristikos

Santrauka Lietuvos teritorijos gravimetrini pagrinda sudaro trys absoliuciuju matavimu punktai bei pirmosios klases gravimetrinis tinklas, jungiantis 48 punktus. Detalesniems Lietuvos teritorijos geopotencialinio lauko tyrimams atlikti sudarytas 635 punktu antrosios klases gravimetrinis tinklas. Tinklas matuotas keturiais gravimet‐rais Scintrex CG‐5. Matavimu rezultatai apdoroti (GRAVSOFT programu paketo procedūros). Pateikiami gravimetrinio tinklo tikslumo ivertinimo duomenys.

The united geodetic vertical network of Latvia and Lithuania

A unified and continuous national vertical network is the back-bone for geodesy, cartography, civil engineering and global positioning. International institutions are working to reach homogenous and unified vertical datum all around the globe. Levelling evaluation on the border between Latvia and Lithuania is of particular interest. Connection between vertical networks is made in three places, so connecting lines construct the two first order levelling loops. A joined loop adjustment produces a good basis for analysis and evaluation of height connection between Latvia and Lithuania not only as neighbouring countries but also as parties to the EVRS.

Measurement Techniques of a European Sea Level Service Site in KLAIPEDA

The technical equipment including hardware and software of European Sea Level Service (ESEAS) station KLAIPEDA (KLPD) is presented in the paper. The tide gauge Klaipeda (previous name – Memel) was established in 1811 in the east part of the Baltic Sea, at the estuaries of Curonian Lagoon. KLAIPEDA ID number at the Permanent Service of Mean Sea Level (PSMSL) is 080161. Upgrading of the station is done according to the ESEAS-RI project (Contract No EVR1-CT-2002-40025). KLPD site was equipped with a digital float tide gauge, sea-water conductivity sensor, air temperature, pressure and humidity sensors, wind speed and direction sensor and GPS receiver with antenna. The four characters ID KLPD and IERS DOMES number 10802M001 was assigned to the permanent GPS station KLAIPEDA. Tide gauge KLAIPEDA was certified as ESEAS Operational Site in 2003. It provides near real time (hourly) data to corresponding data servers. The data warehouse system is built on Gentoo Linux, with Apache2, MySQL 4.0.22 and PHP 4.3.9. The communication structure and software applications are also presented in the paper.