How is temperature measured by a physical oceanographer?

Physical oceanographers commonly measure temperature using instruments like thermistors, which are sensitive temperature sensors, and CTD (Conductivity, Temperature, Depth) sensors that collect data on temperature along with salinity and depth. These instruments can be deployed on buoys, research vessels, or underwater vehicles to gather temperature profiles of the ocean. Data is often collected at various depths to understand temperature gradients and dynamics within different ocean layers. This information is crucial for studying ocean circulation, climate change, and marine ecosystems.