PORP study materials
PORP study resources

PORP: Oceanographic and Meteorological Sensor Systems

PORP · Work through your exam, one topic at a time.

All guide sections

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.