| Wind profile radar (WPR) is a remote sensing equipment to sound vertical distribution and time-variation of atmospheric wind field, atmospheric refractive structure constant Cn2 and other variables just over the radar site, based on the backward scattering signal from atmospheric turbulent parcels or rain droplets. In the case of precipitation, the echo comes from both atmospheric turbulent parcels and hydrometeors due to particle backward scattering. The product of wind field out of the profiler radar is therefore distorted by hydrometeors.Status of profiler radar data quality control in the case of precipitation is firstly introduced in the thesis, principle, signal processing, data processing and quality control is described,characteristics of atmospheric echo are also analyzed in the situations of clear-sky, snowfall,stratiform rainfall and convective rainfall. Atmospheric turbulence can be detected by a profiler radar,but can not be detected by a millimeter-wavelength radar. Considering the difference of atmospheric turbulence detection between profiler and cloud radar, two schemes are proposed to retrieve the vertical wind datafrom profiler measurement, and validated through cases analysis.The result shows, new scheme can eliminate a great deal influence on vertical wind data in the case of weak precipitation. Furthermore, new scheme can effectively retrieve the vertical wind velocity even if the turbulence is very weak.During heavy rainfall, the echo of millimeter wavelength radar is obviously attenuated by the raindrops. The wind profiler radar spectrumis used to do attenuationcorrection for millimeter wavelength radar spectra. Then atmosphere turbulenceis extracted from WPR spectra and modified millimeter wavelength radar spectra. Statistical results shows that 97.65% of modified velocity through this new scheme is lower than 2m/s, but only 14.31% of raw velocity is lower than 2m/s. Such a big difference reflectsthat the new scheme is effective. |
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