Analysis Of Raindrop Size Distribution At Different Altitudes In Mt.Huang

Raindrop spectrum research is of great significance to understand the natural precipitation process. The characteristic of raindrop size distribution in Mt.Huang were analysised using the data observed from June to August and the microphysical parameters at different altitudes were analysised as well as the discrepancy through a precipitation process with a long time and a wide range. It could be concluded that the times of precipitation in June was more in plum rain season in Mountain Huang.The intensity and the last time of each recipitation varied greatly.The duration of stratiform cloud and hybrid was longest,while the cumulus lasted a shortest time with strongest rainfall. The precipitation in the center of local strong cloud and cumulus was greater than that in the fringe area.The raindrop size distribution of cumulus was widest. All of the microphysical diameter parameters on the mountainside was highest and that on the bottom of the mountain was lowest. The rainfall in the mountainside was highest,while the number concentration on the top of mountain was highest. The small raindrops contributed most to the concentration,while the moderate and small ones made the most contribution to rainfall intensity and proportion of small drops on the top of the mountain was largest.On the one hand,it was highest on the mountainside and lowest on the bottom of the mountain that the number concentration for the raindrops whose diameter was less than lmm,which was related to evaporation and collision coalescence. On the other hand, the descending order of that whose diameter larger than1.5mm was mountainside,top of the mountain, bottom of the mountain,which was due to the topographic forcing. The precipitation lasted continuous with many peaks. The spectrum would become wider with more large raindrops when the center of precipitation was closing and the peak of rainfall would appear. Sometimes the maximum rainfall intensity was not corresponding to the largest number concentration,and it would not decrease rapidly when the peak past.It would show high concentration of small drops which maybe due to the wind speed sorting.It was approximate the power function relationship between rainfall intensity and radar reflectivity,number concentration and max diameter with the best coorelation with radar reflectivity. The Gamma distribution fitted well on the overall range,but the deviation was larger on the part of large raindrops. It showed good binomial relation between the shape factor and the slope factor.