The parabolic equation method is a versatile tool for outdoor
sound propagation. The present study has focused on the
Cranck-Nicolson type Parabolic Equation method (CNPE). Three
different applications of the CNPE method have been investigated.
The first two applications study variations of the ground in a
homogeneous atmosphere. Propagation of sound above a mixed
impedance ground and up-slope sound propagation is investigated.
In the third application the influence of the atmosphere is
studied, characterized and implemented in the CNPE-model. The
refraction of the sound due to the wind and temperature gradients
and the scattering due to the turbulence of the atmosphere are
taken into account in the calculations.