Question

Explain what accounts for the presence of a sound channel in the ocean based on how ocean stratification affects sound travel through water.

Answer 1

The speed of sound fluctuates with changes in depth that go with regular changes in salinity, temperature and pressure in the ocean. They may both form a coat of shadow, layers of reflection when the waves are propagated. The greater the temperature of the water, the faster the sound travels for narrower depths. But deeper into the ocean, pressure dominates. The thermocline where the change of temperature is greatly observed, shows a decrease in sound speed with decreasing temperature. The region somewhere in the thermocline where the sound speed is at minimum and allows the transmission of low frequency sound at great distances is called SOFAR or sound fixing and ranging channel. SOFAR channels is greatly affected with depth and thickness.

Answer 2

Water stratification is a phenomenon in which regions of water with different properties, such as salinity, oxygen content, density and temperature, form barriers to mixing of the water.

These barriers also create channels, referred to as sound fixing and ranging (SOFAR) channels. In these channels, the sound has a specified path. It travels slower than normal, but due to reduced dissipation to the surroundings, the sound travels for larger distances.