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The sonar modified for the test was an early version of SURTASS deployed in the MV Cory Chouest. [10] As a result of this test a "Committee on Low-Frequency Sound and Marine Mammals" was organized by the National Research Council. Their findings were published in 1994, in Low-Frequency Sound and Marine Mammals: Current Knowledge and Research ...
"Sonar" can refer to one of two types of technology: passive sonar means listening for the sound made by vessels; active sonar means emitting pulses of sounds and listening for echoes. Sonar may be used as a means of acoustic location and of measurement of the echo characteristics of "targets" in the water. [ 4 ]
It concluded that the effects of mid-frequency active sonar are strongest on Cuvier's beaked whales but vary among individuals or populations. The review suggested the strength of response of individual animals may depend on whether they had prior exposure to sonar, and that symptoms of decompression sickness have been found in stranded whales ...
An important finding is that whales, in a process called the Lombard effect, adjust their song to compensate for background noise pollution. [48] Blue whales stop producing foraging D calls once a mid-frequency sonar is activated, even though the sonar frequency range (1–8 kHz) far exceeds their sound production range (25–100 Hz). [2]
Sonar is the name given to the acoustic equivalent of radar. Pulses of sound are used to probe the sea, and the echoes are then processed to extract information about the sea, its boundaries and submerged objects. An alternative use, known as passive sonar, attempts to do the same by listening to the sounds radiated by underwater objects.
Multibeam sonar is used to map the ocean floor. A multibeam echosounder (MBES) is a type of sonar that is used to map the seabed. It emits acoustic waves in a fan shape beneath its transceiver. The time it takes for the sound waves to reflect off the seabed and return to the receiver is used to calculate the water depth.
The type designation "UQC" stands for General Utility (multi use), Sonar and Underwater Sound and Communications (Receiving/Transmitting, two way). The "W" in WQC stands for Water Surface and Underwater combined. The underwater telephone is used on all crewed submersibles and many Naval surface ships in operation.
A submarine tracking another submarine can take advantage of its target's baffles to follow at a close distance without being detected. Periodically, a submarine will perform a maneuver called clearing the baffles, in which the boat will turn left or right far enough to listen with the forward array sonar for a few minutes in the area that was previously blocked by the baffles.