ASA 130th Meeting - St. Louis, MO - 1995 Nov 27 .. Dec 01

3aPAb2. Influence of turbulent intermittency on acoustic scattering in the atmosphere.

D. Keith Wilson

Dept. of Meteorol., Penn State Univ., 503 Walker Bldg., University Park, PA 16801

The classical treatment of wave scattering by turbulence does not account for the influence of turbulent intermittency. Intermittency causes quantities such as the scattering cross section to vary in space and time. It is particularly important to account for intermittency when there are energetic eddies having dimensions larger than the scattering volume, as is typically the case for scattering problems involving atmospheric turbulence. The conditional-probability method developed by Gurvich and Kukharets for incorporating intermittency effects will be discussed and applied to the problem of acoustic wave scattering by atmospheric turbulence. It will be shown that intermittency can dramatically increase the probability of measuring large values of the scattered intensity. The effect of combined intermittency in the temperature and velocity fields will also be considered.