Preliminary results on observations of chinooks using a Doppler acoustic sounder

Abstract

An acoustic sounder array located on a rural site 20 km west of Calgary is described. The array is designed to sense atmospheric turbulence with a working vertical range of 2 km and also to provide information on the vertical wind profile up to 800 m above the site. The array consists of a central, vertically directed, monostatic array (output acoustic power ∼ 100 W), and four passive inclined receivers, each acting as a bistatic receiver for the central monostatic transmitter. The bistatic receivers are arranged along two mutually perpendicular horizontal baselines. On-line microprocessors are used to retrieve Doppler shift data from all receiver channels, and hence to calculate the wind profile. Typical results from the Doppler acoustic sounder array are presented. It is hoped that by the time of presentation, soundings will have been made during at least one Chinook event (a foehn-type wind associated with airflow over the nearby Rocky Mountains).