How do people use sound underwater?
People use sound in the ocean for a wide variety of purposes. Many important everyday activities, such as fishing, depend on sound for success. A primary use of sound is to locate objects in the ocean, including rocks on the seafloor, marine animals, submarines, and shipwrecks. Sonar (Sound Navigation and Ranging) is a technology that uses sound waves to identify objects and their locations in the ocean. People commonly use sound to determine the depth of the ocean. The most common system for measuring water depth, and preventing collisions with unseen underwater rocks, reefs, etc., is the echo sounder, a form of active sonar. Fishermen use a version of echo sounding technology called a fish finder to locate fish. Sound is used to study marine mammal distributions by listening to the sounds animals make. Different species of whales and dolphins produce different sounds, such as songs, moans, clicks, roars, whistles, and sighs. Each species is unique in its vocalizations. Scientists can
