On transmission of pressure across thermocline to ocean bottom

A direct route for pressure transmission from free surface to ocean bottom is discussed. The ocean is of infinite horizontal extent, the vertical sound profile is composed of three layers: in the upper (mixing) layer the sound velocity is constant, in the intermediate (thermocline) layer the sound velocity decreases exponentially with the depth, and in the lower layer the sound velocity increases linearly with the depth. Equations with easily found closed-form solutions are obtained, and the pressure at the bottom depends upon the sound profile rather than the depth, therefore the effect of free surface may not die out.