Methods for maintaining a stable datum in a sea level monitoring system

The Indo-Pacific Sea Level Network includes an array of automated near-real time satellite telemetering gauges installed in harbors or lagoons of tropical islands and along the continents of the Indian and Pacific Oceans. Most stations were installed and are maintained by the University of Hawaii Sea Level Center, which also collects, processes, and archives the data. The group´s activities include research in sea level measurement techniques and the development of new procedures and equipment. One such area of active research is that of maintaining a stable datum. The University of Hawaii has developed a robust array of instruments that emphasizes redundancy of measurements including an automated switch that produces reference level information. This system and the steps essential to link sea level data to a stable datum are reviewed