A comprehensive and complete understanding of how physical ‎parameters and sound wave propagation change in different places and ‎times is essential and inevitable. The present study examined and ‎evaluated vertical and horizontal changes in temperature, salinity, and ‎sound velocity parameters in the seas surrounding the country's south, ‎including the Persian Gulf, the Strait of Hormuz, the Sea of Oman, and ‎the northern Indian Ocean. The physical parameters of the water column ‎in the two cold and warm seasons of the region have been monitored and ‎analyzed at selected stations in the aforementioned seas from the surface ‎to the bed using the international data of the World Ocean Atlas 2018. ‎The results of the studies indicate the existence of a permanent ‎thermocline layer in the deep regions of the Oman Sea and the northern ‎Indian Ocean, due to which the propagation of sound waves is reduced ‎by more than 30 units. In the Persian Gulf and the Strait of Hormuz, due ‎to the shallowness of the region, the thermocline layer is created only in ‎the warm season of the region, and as a result, a weak sound channel is ‎formed at depths near the bed. It should be noted that in all the studied ‎regions, the propagation speed of sound waves is strongly dependent on ‎the temperature parameter and its resulting changes in the water column ‎are similar to vertical temperature changes. Also, two-dimensional ‎sections indicate the penetration of salty waters of the Persian Gulf into ‎the Oman Sea in layers near the bed throughout the year.‎