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 expectati...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.展开更多
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]+5 种基金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]
文摘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.