Oceanographic and Meteorological Sensor Systems
Domain focus
This domain tests whether you can select, site, and interpret the sensors that produce PORTS observations: water level, currents, waves, meteorology, and water quality.
Sensor families and key principles
- Water level: acoustic (stilling well or bubbler), pressure (needs barometric compensation), radar/non-contact, shaftless float, and GNSS water-level systems. Each has a distinct datum reference and biofouling exposure.
- Currents: acoustic Doppler current profilers (ADCPs) and point meters; ADCPs report bins and ensembles, not a single number.
- Waves: directional buoys, ADCP wave bursts, and pressure sensors; report significant wave height, peak or mean period, and direction.
- Meteorology: anemometer, barometer, temperature/humidity, visibility, precipitation; exposure and mounting height matter.
- Water quality: CTD, turbidity, dissolved oxygen, pH; fouling and calibration drift are dominant errors.
Siting and performance
Mount sensors to sample the water mass or airflow users care about: avoid wakes, eddies, structure shadowing, and sediment. Specify accuracy, resolution, range, sampling rate, and environmental limits. Build in redundancy and a calibration plan. System accuracy is not the same as sensor accuracy: mounting, datum, and processing add error.
Worked example
For a tide gauge at an exposed container berth, a non-contact radar avoids fouling and stilling-well siltation but needs a stable mounting and a local datum reference; a pressure gauge needs barometric compensation and can drift with fouling. The choice follows the site, not a favorite brand.
Traps
Using an uncompensated pressure sensor as a tide gauge; placing an anemometer behind a crane; quoting sensor resolution as system accuracy; ignoring biofouling and calibration intervals.