Comparative analysis of two ice particle processes based on millimeter wave cloud radar
A comparative analysis was conducted on two precipitation weather processes with ice particles at Daxing Airport by using Ka-band millimeter wave radar,wind profile radar data,and reanalysis data.Results indicate that:(1)the circulation pattern is characterized by the passage of high-altitude troughs,with southwest rapids and abundant water vapor in the middle layer,but there are significant differences in the atmospheric environment near the surface layer.(2)The cloud top height exceeding the-10 ℃ line height during the two processes is a mechanism of ice melting.The vertical atmospheric environment is not always characterized by"cold-warm-cold",and there is also a situation of upper cold and lower warm.(3)The non-singularity of precipitation particles results in a linear depolarization ratio Ldr below the 0 ℃ layer,which is not only greater than the non-ice particle stage,but also far greater than above the 0 ℃ layer,and its characteristics are not affected by precipitation intensity.(4)The reflectivity factor is significantly stronger in the 0 ℃ layer and below than in the 0 ℃layer above,mainly caused by changes in precipitation intensity,and its characteristics have little correlation with particle phase.(5)During the two processes,the falling velocity and velocity spectral width of particles exhibit opposite trends,and during the ice particle stage,their characteristics are within the range of transition values between rain and snow.At the same time,the vertical velocity characteristics of the ice particle stage of the wind profile radar are also consistent with the velocity characteristics of the millimeter wave radar.
万方数据
维普
