Using the boundary layer wind-profiling radar we did the detection experiment study on the processes of sandstorm, rainfall and snowfall. The emphasis is put on the analysis of the echo signal and velocity power spectrum distribution during the process of sandstorm, and the observed wind data in the process is evaluated as well. The echo intensity value range of sandstorm is calculated and summarized and the high-level particle number concentration and mass concentration of sandstorm is quantitatively inversed and estimated. In addition, from the perspectives of wind detailed analysis, frontal system identification, temperature advection inversion, echo intensity, etc., we investigate the technical method of applying the high resolution wind profiler data to the rainfall (snowfall) weather analysis in arid areas. The main conclusions are as follows:
(1) When the CFL-03 boundary wind-profiling radar works in dry sandstorm weather, atmospheric refraction index is small, turbulence echo signal is weak, but the sand particle group produces strong backscatter to the electromagnetic wave. The wind-profiling radar mainly identifies the returning signal of sands, ignoring the scattering echo signal of atmospheric turbulence.
(2) Effective data acquisition rate of the CFL-03 radar is low during the process of sandstorm. The effective data acquisition rate can go over 40% under 2,000 m height, ranges within 20%-40% between the 2,500-4,000 m height and lower than 20% above 4,000 m. One critical factor that impacts the wind-profiling radar to detect wind effectively is the dry atmosphere and low relative humidity. The result that RASS system detects the virtual temperature during sandstorms is not so ideal, and the effective detected height is mostly lower than 500 m. The important cause for the unsatisfactory temperature observation is that the sandstorm reduces acoustic waves seriously and the returning signal is very weak.
(3) The sandstorm weather phenomenon leaves clear signets on the radar echo intensity time-height diagram, by which the height and thickness of sands carried by the storm can be identified and the vertical distribution of sands can be reflected. Equivalent radar echo intensity of flying sand and sandstorm weather varies in the range of -1～13dBZe.
(4) Vertical shear of horizontal wind and the sustainment of low-level easterly are the dynamic causes for the occurrence of sandstorm weather in Taklimakan Desert. The moment when low-level wind ...