R2Sonic 2026, Operation Manual

Page: 174 / 254

Page 174 of 254
Version 6.3 Rev r012
Date 05-11-2022
Part No. 96000001
Figure 184: Concept of refraction due to different sound velocities in the water column
The velocity of sound in water varies both horizontally and vertically. It cannot be assumed that the
velocity of sound in the water column remains constant over large areas or throughout the day in a
more local area. The main influences on sound velocity are Conductivity (salinity), Temperature, and
Depth (pressure).
1 ° C change in Temperature = 4.0 m/sec change in velocity
1 ppt change in Salinity = 1.4 m/sec change in velocity
100 m change in Depth (10 atm’s pressure) = 1.7 m/sec change in velocity
Figure 185: Sound velocity profile