Correlation Between The Cloud Characteristic Parameters Retrieved By FY Satellite And Precipitation And Rocket Rain Enhancement Of Cumulus Mixed Clouds In North China

Compared with the aircraft,the rocket has advantages like less investment,work time unrestricted by the season in artificial rainfall enhancement.At present,although the scale of the rocket operation is large,the scientific nature of operations is not high,and the blind operation happens occasionally.How to guide the ground rocket to carry out seeding cloud catalysis scientifically and reasonably is not only a good scientific research problem,but also an urgent professional work problem to be solved.Retrieval products by FY serial satellites and rainfall data were used to discuss the correlation between cloud parameters and precipitation.In addition,a method of monitoring and early warning the ground rainfall areas and intensity using the cloud parameters by FY satellite was explored,and the potential areas for precipitation enhancement were identified.The combination of satellite data,observational rainfall data,numerical model products,radar and sounding data was analyzed for a typical rainfall process of cumulus mixed clouds on 13-14^thh May in 2016 in North China.Specially,the opportune time when the seeding cloud catalysis should operate was analyzed deeply.The results are as follows:?1?On the probability of precipitation,cloud optical thickness was the most significant index of precipitation among the four kinds of cloud parameters.When cloud optical thickness was greater than 20,the probability of precipitation increased remarkably.The other indexes of precipitation were cloud top temperature,cloud top height and effective radius of cloud particles successively.Moreover,the double parameters combination of cloud optical thickness and cloud top temperature was better than a single cloud parameter to determine and identify if the precipitation happens.?2?Five satellite monitoring indexes and criterions of indentifying the potential areas for precipitation enhancement were obtained.Firstly,a)When the cloud optical thickness was greater than 20 but less than 30 and the cloud top temperature was less than-15?;b)When the cloud optical thickness was greater than 30 but less than 40 and the cloud top temperature was greater than-45?but less than-15?,c)When the cloud optical thickness was greater than 40 and the cloud top temperature was greater than-35?but less than-15?,if one index appeared among the above three indexes,the potential area for precipitation enhancement was indentified.?3?In order to distinguish the operation opportunity,the double-parameter index derived by FY satellite was used to identify the potential areas for precipitation firstly.Secondly,the data obtained from ground radar,radiosonde and microwave radiometer was analyzed on 13^th-14^thh May in 2016 in Shijiazhuang.The results showed 19:00-21:00 on 13^thh May and 07:00-12:00on 14^thh May were the propitious moment for the ground rocket operation.Rationality analysis of 10 operation points indicated that the second,fifth and sixth points were invalid,the others were effective points because the target clouds stationed in the rocket effective catalytic region.?4?Based on CPAS platform,multi parameter region dynamic contrast method was adopted to test the rain enhancement effectiveness of 7 operation points for a precipitation case on 13^th-14^thh May in 2016.The results showed that after the rain enhancement operation,the average value of radar echo intensity and the average rainfall within 1 hour in the affected zone were greater than the compared zone in six operation points,for example,Jingxing?the fourth points?.While in Gaocheng point,the average value of radar echo intensity and the average rainfall were less than compared zone.