Measurement Techniques of a European Sea Level Service Site in KLAIPEDA

Abstract

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.

XML Data Schemas and Scalable Vector Graphics Format for the Sea Level Observations

“…Second, XML gives an opportunity to use SVG as vector graphics format -very powerful technology to visualise the technological data without loosing ability to check or parse raw textual data. For example, graphical representation of sea level hourly means data from KLPD site is presented in Fig 2. Excerpt from the simple source code of SVG file, representing the results of sea level observations, is given in Fig 3. <...> <xsd:element name="formInformation" type="mi:formInformationType"/> <xsd:element name="siteIdentification" type="mi:siteIdentificationType"/> <xsd:element name="siteLocation" type="mi:siteLocationType"/> <...> <xsd:element name="waterVaporSensor" type="equip:waterVaporSensorType"/> <xsd:element name="otherInstrumentation" type="equip:otherInstrumentationType"/> <...> <xsd:element name="contactAgency" type="contact:contactInformationType"/> <xsd:element name="responsibleAgency" type="contact:contactInformationType"/> <xsd:element name="moreInformation" type="mi:moreInformationType"/> <...> Still, hourly SVG files are formed with the help of the file written in PHP scripting language [9]. Data from the sensors is transmitted to the server, where MYSQL query is formed and put on the MYSQL database.…”

“…Data from the sensors is transmitted to the server, where MYSQL query is formed and put on the MYSQL database. When PHP file that forms SVG with XML Data Schemas is accessed, it takes last hour's means from database and forms a corresponding SVG file, which can be saved to local hard drive [7,9].…”

“…Data exchange for marine research sites is extremely important and valuable [1][2][3][4][5][6][7][8]. At present TGX format (only ASCII data) is used for sea level observations data exchange [9][10]. Since CSV (comma separated values) or SDF (standard data format) format save place and as raw textual data can be exchanged, interpreted and imported easily, therefore graphical representation of data remains complicated.…”