Roger Revelle
R/V Roger Revelle

Conductivity, Temperature, and Depth (CTD) sensors are in situ instruments that measure water depth, pressure, salinity, temperature, and density in the ocean. CTD sensors can be deployed on various water-based platforms, including autonomous underwater vehicles (AUVs), buoys, gliders, and research vessels. When mounted on a vessel, CTD sensors are typically attached to a rosette and lowered to the seafloor to record water properties. These sensors typically sample at 30 Hz and can provide accurate measurements at specific water depths, tailored to the researcher's needs.

Generic-Atmospheric State (Gen-AtmsState) refers to non-specific instruments on a platform that measure atmospheric state parameters. These are typically in situ sensors that measure temperature, pressure, humidity, and wind speed and direction. Types of atmospheric state instruments include thermometers, hygrometers, barometers, and anemometers.

The Acoustic Doppler Current Profiler (ADCP) is an in situ acoustic sensor that measures ocean currents. It uses the Doppler effect to detect sound waves, providing measurements of current speed and direction throughout the water column. It can be easily mounted on various water platforms, such as ships, buoys, and autonomous underwater vehicles (AUVs). Additionally, it can be deployed on the seafloor to provide profile measurements of ocean currents.

Gravimeters are passive sensors that measure the strength of Earth’s gravitational field. These measurements are used to determine rock density variations, support oil and mineral prospecting, monitor glacier changes, and study volcanic activity. Gravimeters can be used for both airborne and ground-based operations.