【摘要】 在2002~2003年春秋季陕西省14次飞机增雨作业天气分析的基础上,对2002年9月13日飞机增雨作业典型天气个例的环流背景、影响系统以及500 hPaθse、温度、垂直速度、水汽通量散度等物理量场进行了分析,并结合飞机和雷达探测资料,得出飞机增雨作业需要的有利于层状云向降水转化的条件:有稳定的层状云,云系有一定冷层厚度和过冷云水量,供自然冰相降水元和人工催化形成的降水元增长;云系还应有一定厚度的暖层,供下落的自然和人工形成降水元融化再经碰并云水增长成雨滴形成降水。陕西省春秋季具有进行有效飞机增雨作业的天气系统和天气条件。更多还原

【Abstract】 Based on the synoptic analysis of 14 aircraft cloud seeding operations in spring and autumn in 2002 and 2003,a typical seeding case study of 13 September 2002 was conducted,in which an analysis was made of the circulation background,influencing systems and the associated physical quantitites such as 500 hPa θ_se vorticity,vertical velocity,water vapor flux,divergence,etc,in combination with aircraft and radar sounding data.The conditions favorable for aircraft rain enhancement operations and needed by the conversion from stratiform clouds to precipitation include: there exist stable stratiform clouds with a cold layer of a certain depth and with enough supercooled cloud water to allow both natural and artificial water particles to grow;the clouds should also have a warm layer of a certain depth to allow the falling water particles to melt,collide,and grow into raindrops.There are favorable weather conditions for rain enhancement in spring and autumn in Shaanxi Province.更多还原