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

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.