Radar-Measured Height Profiles of Cn(2) and Turbulence Dissipation Rate Compared with Radiosonde Data during October 1989 at Denver

摘要

Profiles of radar reflectivity and Doppler spectral width, for the month of October 1989, were recorded with the Stapleton 32-cm-wavelength wind profiler. The data were analyzed for hourly intervals centered on radiosonde release times, and each hour was divided into two half-hourly subperiods so that four half-hourly periods of radar data were typically analyzed for each day. The resulting profiles of the turbulence structure parameter for radar refractive index (C Dup n, Sup 2) extracted from backscattered power and of turbulence dissipation rate (actually (C sub w, sub 2) extracted from Doppler spectral width are presented with the temperature, dew point, and refractive index profiles measured by radiosonde and plotted to the same height scale. The presence of elevated temperature inversions and humidity gradients is examined and compared with radar profilermeasured quantities. A case when clouds were present is considered in some detail, because clouds are a very important source of potential false alarms in any method using radar reflectivity data to extract refractive index or humidity profiles. The experimental precautions needed to achieve the desired accuracy are discussed.