An innovative technique for the development of the traditional mechanical tide gauge to improve the performance of the measurement system

Abstract

Over the last decades, interest in high-quality sea-level reads and higher-accuracy tide gauges has increased because of concern about the sea-level rise induced by climate change. As a response, tide gauge networks were also updated by which the traditional mechanical tide gauges were gradually substituted by modern gauges provided with acoustic, pressure and radar sensors. This study presents an innovative technique for the development of the traditional mechanical tide gauge using a cylinder capacitance meter to upgrade the efficiency of the device and the precision of the measurements. A new type of non-contact capacitance water level sensor is designed and fabricated. Furthermore, an electrical and electronic circuit was built for converting the mechanical process of traditional tide gauge resulted from variation in water level to digital form and data storage for a one-year capacity. The performance of the developed tide gauge was evaluated using the Van de Casteele test, which depends on comparing differences of water level data measured by a reference pressure tide gauge with the developed one over a certain period. Results indicate that the developed tide gauge is perfectly suitable to measure the variations in sea level and thereby can be communicated to the tide gauge networks. Moreover, the accuracy of the new tide gauge is compatible with the requirements of the Global Sea Level Observing System (GLOSS) “1-cm accuracy ", with a minimum Root Mean Square of <1 ​cm.