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利用2007年飞机探测资料,对河北地区云微物理结构进行了分析。结果表明,高层云底部云滴数大于中上部,随高度增加粒子直径增大。最大云中液态水含量为0.25g.m-3,底层平均云中液态水含量为0.025g.m-3。层积云中上部数浓度高于底部,云滴数浓度变化范围为10-80cm-3,云滴平均直径为7.56μm,总趋势随高度增加云滴直径先增大后减小。云滴谱变窄、双峰消失与含水量的起伏有一定的关系。综合增雨作业资料,发现有时预设的飞机作业高度并不是十分合理,在飞机性能条件允许的情况下,可以适当提高或降低作业高度,人工增雨的效果可能更好。鉴于作业层的温度,9月29日和13日可以考虑使用液氮或液态CO2等制冷剂进行催化。“,”The cloud microphysical properties are analyzed based on the aircraft measurements conducted over Hebei region,Northern China during autumn of 2007.The results show that the droplet number on the bottom layer of altostratus is greater than that on the upper layer,and the particle diameter increases with height.The maximumn content of liquid water is 0.25 g·m-3,and the average content of liquid water is 0.025 g·m-3 at the bottom.It is also shown that the concentration of cloud droplet on the upper layer were higher than that on the bottom,the droplet number concentration ranges from 10 to 80 cm-3.The diameters are around 7.56 μm,with height increasing the particle diameter increases first and then decreases.Cloud droplet spectrum narrows and the disappearance of two peaks are cloud droplet related with the change of water content.Comprehensive analysis of cloud microphysics structure suggests that planning in advance the flying pattern is possibly not the best scheme for cloud seeding in some cases,and the seeding operation should be designed based aircraft condition and weather as well as cloud conditions.In view of the temperature,it could be considered using the catalytic of liquid nitrogen or liquid CO2.