ADIABATIC MODES FOR A POINT-SOURCE IN A PLANE-GEOMETRY OCEAN

The adiabatic-mode solution is widely used for modeling sound propagat ion in slowly varying ocean environments. However, there are several v ariations of adiabatic mode solutions and there has been confusion abo ut which form is correct. The standard derivation yields a form that i s not reciprocal. As such, it has often been modified in an ad hoc fas hion to produce a form that is reciprocal. This lack of reciprocity is due to the common assumption that the environment is rotationally sym metric about the source. By assuming instead a plane-geometry environm ent a new adiabatic form that is reciprocal is derived.