ABSTRACT
A fast field program, which is a powerful method of modern mathematical computing, has been used for the investigation of sound propagation near ground with a finite impedance in a stratified atmosphere [144, 150,223]. The parabolic equation method, widely used in different fields of physics, has also been adopted for calculating sound fields propagating in the atmosphere [91]. A comparison between the different numerical techniques which are now used to calculate the sound field in a stratified atmosphere has been given elsewhere [10].
