- Abbreviation of sound fixing and ranging channel. Within the ocean, a channel via which acoustic waves travel nearly horizontally due to refraction. Reductions in water temperature result in lower sound speed, while increases in pressure speed up sound. Since sound tends to bend, or refract, towards a region of lower sound speed, a horizontal channel is formed, as the sound waves are refracted down by the temperature reductions, and up again by the pressure increases.
- synonymsound fixing and ranging channel