A tide gauge for use in remote areas

A prototype tide gauge having an accuracy of\pm0.5% of the tidal range and a resolution of\pm0.1% suitable for unattended use over one year is described. It is based on an Aanderaa data logger and a differential pressure transducer installed together on the sea bed; tidal data is recorded internally, digitally at half hour intervals. A cable containing electrical conductors and a kerosene-filled hose rises to the shore allowing air pressure to be sampled, calibration to be checked, and telemetering/ transponding equipment to be attached. The instrument has been in limited commercial production; the first unit was installed at 801/2\degN. during August, 1972.