RASS - A new remote sensing system for the surveillance of meteorological dispersion

The combination of acoustic and radio waves called PASS (Radio Acoustic Sou nding System) allows ground based measurements of the vertical profiles for temperature, wind and turbulent parameters. The technique uses the scatter ing of the radio waves at the density fluctuations caused by the acoustic w ave field Compared to SODAR or RADAR techniques which have proven their rel iable routine operation in various applications RASS shows no sensitivity t o fixed echo, to environmental noise or to precipitation. The height range of the RASS sounding is limited only by the atmospheric absorption of the s ound waves and the shift of he acoustic wave with the mean field Depending on the specific choice of acoustic and radio operation frequencies and the geometric configuration of the antennas RASS can be optimized for profiling in height ranges of some hundreds meter to some kilometer. In view of on-l ine environmental monitoring at industrial sires PASS allows direct measure ments of the profiles of the meteorological parameters for transport and di spersion, atmospheric stability and the formation and decay of inversions.