A new approach to sea level observations in Croatia

Abstract

The paper comprises an overview of recent international and national efforts and activities directed towards the improvement of tide gauge network on the eastern coast of the Adriatic Sea. A brief overview of the available measuring techniques is given first. Then the characteristics of Adriatic sea level are outlined, followed by a note on the history of sea level measurements and research in the Adriatic. The present sea level related activities are introduced by the institutional structure in Croatia, followed by a summary of recent projects and programmes (European Sea Level Service – Research Infrastructure (ESEAS-RI), Mediterranean Global Observing Sea Level System (MedGLOSS), Project Adriatic and Adriatic Tides and Sea Level On-line). Concrete activities on the upgrade of Croatian tide gauges, data acquisition and maintenance, and on-line data presentation are presented in detail. In addition, the initiation of measurements of vertical land movements is documented, as a Continuous GPS antenna and receiver (CGPS) has been installed in 2004 at the roof of the Split Harbour tide gauge. A lot of effort has been put into the rescue of historical sea level records, both by digitising and scanning of the charts, which will prevent data loss in case of their ruination or disappearance. Finally, the impact of the recent activities on the scientific exploration of high-frequency resonant coupling of air pressure disturbances with the eastern Adriatic waters is highlighted in the paper, as such research is not possible to carry out properly with the measuring systems based on the analog records.