冰雪晶二维图像及霰粒子谱特征分析

分析了１９９１－１９９３年人工降水期间共１３个架次粒子测量系统（ＰＭＳ）获取的冰、雪粒子的二维图像资料，分析了雪粒子的形态特征，重点分析霰粒子出现的频率及其尺度谱特征；并利用霰粒子的直径大小，在一定的假设条件下，估算了观测高度以上云中所包含的过冷水的累积含量；借以了解飞行层以上的的人工降水潜力状况。初步分析结果表明，不少架次的飞行过程都出现有持续时间不等的霰粒子，估算出的最大积分过冷水含水量为１３

An Analysis of Two-dimensional Image of Ice and Snow Crystal and the Size Distribution of Graupel Particles

The two-dimensional image data of ice and snow particles and the shape features of snow particles and the shape features of snow particles from the measurements of 13 flights equipped with the particle Measuring System (PMS) during 1991-1993 are analyzed,with the focus on the occurrence frequency and the size distribution of graupel particles. Based on certain assumptions,the accumlated super cooled water content in the clouds above the oberservational level is estimated according to the diameters of graupel particles,so as to find out the potential of artificial precipitation above the operating level. The primary results indicate that graupel particles were found in .the operating processes of many flights of different durations; the estimated maximum integrated supercooled water content is 130 g/m2. It can be seen from the duration percentages of graupels in the processes of the flights that supercooled water is distributed horizontally and the graupel particle percentage varies greatly in different flight. In addtion,the comparison of the data obtained in the same flight indicates that the higher the altitude and the temperature, the lower graupel particle percentage is observed.