Justification of the Use of Multiple Isothermal Layers as an Approximation to the Real Atmosphere for Acoustic‐Gravity Wave Propagation

The validity of the multilayer approximation for the study of acoustic‐gravity wave propagation in the atmosphere is demonstrated in the limit of small layer thicknesses. The principal basis of the justification is the existence of two coupled first‐order differential equations with coefficients which do not depend explicitly on derivatives of the sound speed with respect to height.