通过飞机直接进入降雪云进行探测，并配合MICPAS、雷达和卫星等资料，对2011年11月29日山西一次降雪云宏微观结构特征进行分析。研究发现：本次降雪过程的雷达回波以10~20dBZ大片层状云回波为主，镶嵌了超过30dBZ的块状强回波，雷达径向速度零线呈较强的“S”型弯曲，出现“牛眼”结构，从低层到高层有较强的风垂直切变。液水含量主要位于3.2km以下，最大值为0.0697g m-3，冰雪晶数浓度N50、N200和冰水含量主要产生于层积混合降雪云的上部，极大值出现在-9.3℃附近，分别为188.4L-1、33.5L-1和0.121g m-3。-14.4~-19.7℃冰晶图像以针状、柱状和不规则状为主，以冰晶的凝华增长为主。-9.3℃附近冰雪晶图像以辐枝状、不规则状为主，辐枝状冰晶的聚并碰撞和折裂繁生可能是造成此处冰雪晶高浓度的主要原因。利用指数形式能较好地拟合冰雪晶谱分布，谱拟合参数可以用幂函数Nos=1.021λ1.684表示，相关系数R2为0.86。3.2km以下存在三次逆温，逆温层的出现使云微物理特征量和拟合参数Nos减小，抑制了云内淞附增长和凝华增长，导致本次观测谱拟合参数Nos、λ随温度的变化规律与以往的观测不一致，逆温强度越大抑制作用越大。
Based on the aircraft directly entering the snowfall cloud with the data of micpas, radar and satellite, the macro and micro structure characteristics of heavy snowfall cloud under the influence of Reflux system in Shanxi Province on November 29th, 2011 were analyzed. It is found that the radar echo of this snowfall process was mainly between 10 and 20dBZ large stratiform cloud echo, inlaid with more than 30dBZ massive strong echo.The zero line of radar radial velocity had a strong "s" curve with a bull"s-eye structure. There was a strong wind vertical shear from the lower level to the upper level. The liquid water content was mainly below 3.2km and the maximum value was 0.0697 g m-3. The ice and snow crystal number concentration N50, N200 and ice water content were mainly produced in the upper part of the stratiform mixed snowfall cloud, and the maximum values appeared near -9.3℃, which were 188.4L-1, 33.5L-1 and 0.121g m-3 respectively. From -14.4 to -19.7 ℃ the images of ice crystals were mainly needle, columnar and irregular and ice particles grew mainly by deposition. The images of ice and snow crystals near -9.3℃ were mainly dendritic and irregular. The aggregation, collision and fracture of radial dendritic ice crystals may be the main reason for the high concentration of ice and snow crystals. The distribution of ice and snow crystal spectrum can be well fitted by the exponential form. The spectrum fitting parameters can be expressed by the power function Nos=1.021λ1.684 and the correlation coefficient R2 was 0.86. There were three inversion times below 3.2km. The appearance of inversion layer made the cloud microphysical characteristics and fitting parameter Nos decrease and inhibited the growth of riming and deposition. As a result, the variation of fitting parameters Nos and λ with temperature in this observation was inconsistent with the previous observation. The greater the inversion intensity was, the greater the inhibition effect was.