Analysis of Ice Crystal Habits and Concentrations of a Stratiform Cloud System over East China Based on Horizontal and Vertical Observation by Aircraft

Li Luping; Zhou Yuquan; Liu Siyao; Yang Ling; Cai Zhaoxin; Wang Yang; Song Can; Li Jing; Gao Yang

doi:10.16765/j.cnki.1673-7148.2025.01.001

Abstract：Based on aircraft horizontal and vertical observation of a stratiform cloud system over East China on October 22,2018,and combined with satellite images,radar and sounding data,we analyze the microphysical structure,ice crystal habits and concentration characteristics of different parts of this cloud system.The results show that in the initial cloud layer near the cloud top,the ice crystal number concentration was relatively lower,the particle spectrum width was narrower,and the highest average concentration of hexagonal was approximately 0.1761 L-1.With the development of the cloud system,the supercooled liquid water content,ice crystals number concentration,and the particle spectrum width in-creased in the mature cloud layer.Except for the graupel particles,the average concentration of ice crys-tals with other habits increased,and the most obvious increase was the average concentration of tiny ice crystals increased by about 62 times.In the vertical direction,the stratiform cloud was layered.In the mature and deep stage,the average concentration of tiny ice crystals in the ice-water mixing zone reached 13 L-1,followed by the concentrations of hexagonal,irregular and aggregate ice crystals.In the ice cloud area,the average concentration of tiny ice crystals decreased to around 0.1 L-1,and hexagonal,irregu-lar,dendrite and aggregate ice crystal were dominant.Meanwhile,the concentrations of sphere,linear and oriented ice crystals were lower in the cold cloud layer.In the weakening stage,the tiny,hexagonal and irregular ice crystals were dominant in the shallow clouds.Compared to those of mature and deep clouds in the same heights,the amount of supercooled liquid water decreased,the particle spectrum width became narrower,and the concentrations of various habits of ice crystals decreased,with a differ-ence of about 1-2 orders of magnitude.