An observational study of lee waves using radiosonde data

Abstract

Corby (1957) showed that radiosonde data could be used to detect departures of the ver- tical velocity of the instrument, of a few m sec-l, from a mean value. Occasionally marked periodic variations of the vertical velocity along the path of the balloon suggested the presence of atmospheric gravity waves, almost certainly due to orography, extending through considerable depths of the atmosphere. Corby limited his study to levels below 40 000 ft; however, on some occasions the waves which he inferred maintained considerable vertical velocities up to this level and may have extended considerably higher. I n the present investigation improved British radiosonde data have been examined for indications of small-scale air motions at all levels. Some emphasis has been placed on motions in the lower stratosphere, which have considerable practical interest in view of the imminent operation of supersonic aircraft there.