Prediction and Monitoring of Clear Air Turbulence: An Evaluation of the Applicability of the Rawinsonde System

摘要

Results from an investigation of the applicability of Rawinsonde data for either detection or prediction of clear air turbulence (CAT) are discussed. The mechanism currently believed responsible for the development of CAT is reviewed. Since previous studies have determined that the most significant factor for the existence of turbulent layers is the magnitude of the vertical shear, certain theoretically derived shear criteria are applied to statistical and diagnostic comparisons of Rawinsonde and Jimsphere/Jimsonde conjunctive vertical profiles. It is determined that, apparently because of its inherently inadequate wind tracking ability and limited vertical resolution, the Rawinsonde system cannot reliably be used as a CAT detector in a "single-station" sense. Information on tendencies of meteorological parameters important at the synoptic scale for the development of CAT layers, however, may be extractable from a horizontal grid of Rawinsonde ascents by using the "Diagnostic Richardson Number" technique.