摘要
选取在庐山不同高度处测得的一次对流云降水过程资料,结合Hu等相关研究结果,分析了雨滴下落过程中各种物理机制的重要作用,并采用两种不同的水滴下落末速度经验公式,分别比对了不同高度处雨滴下落的末速度。所得结论如下:蒸发作用降低了小雨滴(D≤0.3 mm)和较大雨滴(1.5 mm<D<3.0 mm)的数浓度,增加了中等大小雨滴(0.3 mm<D≤1.5 mm)的数浓度。大小雨滴在降雨不同时期和不同高度对含水量的贡献是不同的。雨滴直径在0.5～5.0 mm区间内,下落末速度经验关系式V(D)=9.65-10.3e-0.6D适用于海拔较高处;雨滴直径大于5.0 mm时,经验关系式V(D)=3.778D0.67适用于海拔较低处。
The thesis chooses the data on the process of convective precipitation observed at different altitudes in Lushan,and analyzes the important role of the various physical mechanisms when raindrop falling,referring to Hu et al research results.While using two empirical formulas of the fall final velocity of water droplets,we compare the fall final velocities of water droplets at different altitudes separately,and the conclusions are as follows： evaporation decreases the number concentrations of small raindrop（D≤0.3 mm） and large raindrop（1.5 mm＆lt;D＆lt;3.0 mm）,and increases the number concentration of medium sized raindrop.The contributions of different sizes raindrops to water content are different at different precipitation periods and altitudes.When raindrop diameter is between 0.5 and 5.0 mm range,the empirical formula V（D）=9.65-10.3e-0.6D is applied to higher elevations;and when diameter is greater than 5.0 mm,the other one V（D）=3.778 D0.67 is applied to lower elevations.
出处
《气象与环境科学》
2013年第2期26-30,共5页
Meteorological and Environmental Sciences
基金
国家973全球变化重大科学研究项目(2010CD950804)资助
关键词
雨滴谱
物理机制
速度拟合
raindrop spectrum
physical mechanism
velocity fitting
