Drifter (oceanography)

In oceanography, a "drifter" refers to a buoyant device that is deployed in the ocean to measure and record various physical parameters of the water. These devices are often equipped with GPS and a suite of sensors that allow them to collect data on ocean currents, temperature, salinity, and sometimes other variables like pressure or chlorophyll concentration. Drifters float along with ocean currents, allowing researchers to track these currents over time and space.