Observational Evaluation and Analysis Process of Sound Channel Forming and Sound Speed Changes in Eastern Part of the Southern Coastal Waters of the Caspian Sea

In this study, possibility of establishing sound channel in the southern coastal waters of the Caspian Sea has been evaluated. The research is based on data analysis from field measurement data of temperature, salinity and pressure in the southern boundary of the Caspian Sea. The results show that water temperature changed between 17.9 and 9.2 degree from surface to the bottom and vertical changes of salinity were between 12.06-12.67. Sound speed in the water column varied between 1488 to 1460 m/s from surface to depth of 42 m with a rapid decrease across thermocline layer. Vertical structure of seawater temperature follows the vertical sound speed changes which indicate a high correlation between these parameters. According to the results, the sound channel in the shallow waters of the eastern part of the southern coast of the Caspian Sea was not observed.