摘要
研究目的:介绍暖云降水之谜,总结湍流起伏和夹卷对云滴谱拓宽和暖雨形成过程的影响,包括观测、实验、模拟和理论方面取得的成果。重点阐述我国上世纪五六十年代在湍流起伏方面的突出成绩。重要结论:过饱和度、云滴数浓度、含水量和垂直速度等的起伏对凝结和碰并过程有显著影响。中国和俄罗斯科学家最早把随机凝结过程引入到云物理研究中。夹卷过程可能是暖云降水之谜的一个解。系统理论表明:湍流强度越大,云滴谱越宽。
In the study of warm clouds,there are many outstanding questions.Cloud droplet size distributions are much wider,and warm rain is initiated in a shorter time and with a shallower cloud depth than theoretical expectations.This review summarizes the studies related to the effects of turbulent fluctuations and turbulent entrainment-mixing on the broadening of droplet size distributions and warm rain initiation,including observational,laboratorial,numerical,and theoretical achievements.Particular attention is paid to studies by Chinese scientists since the 1950s,since most results have been published in Chinese.The review reveals that high-resolution observations and simulations,and laboratory experiments,are needed because knowledge of the detailed physical processes involved in the effects of turbulence and entrainment-mixing on cloud microphysics still remains elusive.The effects of turbulent fluctuations and entrainment-mixing processes have been unrealistically separated in most theoretical studies.They could be unified by further advancement of a systems theory into a predictive theory.Developing parameterizations for the effects of fluctuations and entrainment-mixing processes is still in its infancy,and more studies are warranted.
基金
supported by the National Key Research and Development Program of China[grant number 2017YFA060 4000]
the China Meteorological Administration Special Public Welfare Research Fund[grant number GYHY201406001]
the National Natural Science Foundation of China(NSFC)[grant number 91537108]
the Natural Science Foundation of Jiangsu Province,China[grant number BK20160041]
the U.S.Department of Energy’s BER Atmospheric System Research Program[grant number DE-SC00112704]
the Six Talent Peak Project in Jiangsu,China[grant number 2015-JY-011]
the 333 High-level Talents Training Project in Jiangsu[grant number BRA2016424]
the NSFC[grant number 41305120]
关键词
云滴尺度谱
暖云
湍流起伏
夹卷混合
系统理论
Cloud droplet sizedistribution
warm rain
turbulent fluctuation
entrainment-mixing
systemstheory