This paper presents a method to distinguish and link inhomogeneous mixing with subsequent ascent and collision-coalescence. Three stratocumulus clouds analyzed were collected over the U.S. Department of Energy's A...This paper presents a method to distinguish and link inhomogeneous mixing with subsequent ascent and collision-coalescence. Three stratocumulus clouds analyzed were collected over the U.S. Department of Energy's Atmospheric Radiation Measurement Southern Great Plains site during the March 2000 cloud Intensive Observation Period. The criteria are presented to distinguish the two processes. Inhomogeneous mixing with subsequent ascent is identified if cloud along an aircraft horizontal leg is non-drizzling and the relationship between cloud volume-mean radius and liquid water content is negative; in contrast, drizzling and positive relationship between the above two properties are the criteria for collision-coalescence. To link the two processes, threshold function, the possibility of occurrence of collision-coalescence, is employed; the big droplets generated during the in-homogeneous mixing with subsequent ascent increase the threshold function, initiates collision-coalescence and produces drizzle drops. To the authors' knowledge, this is the first study on distinguishing and linking inhomogeneous mixing with subsequent ascent and collision-coalescence based on observational data.展开更多
基金LIU and Lu was supported by the U.S. Department of Energy (DOE) Earth System Modeling (ESM) Program via the FASTER Project (www.bnl.gov/esm)and At-mospheric System Research (ASR) ProgramNiu was supported by the Qing-Lan Project for Cloud-Fog-Precipitation-Aerosol Study in Jiangsu Province, Chinaa Project Funded by the Priority Academic Program Development of Jiangsu Higher Education Institutions
文摘This paper presents a method to distinguish and link inhomogeneous mixing with subsequent ascent and collision-coalescence. Three stratocumulus clouds analyzed were collected over the U.S. Department of Energy's Atmospheric Radiation Measurement Southern Great Plains site during the March 2000 cloud Intensive Observation Period. The criteria are presented to distinguish the two processes. Inhomogeneous mixing with subsequent ascent is identified if cloud along an aircraft horizontal leg is non-drizzling and the relationship between cloud volume-mean radius and liquid water content is negative; in contrast, drizzling and positive relationship between the above two properties are the criteria for collision-coalescence. To link the two processes, threshold function, the possibility of occurrence of collision-coalescence, is employed; the big droplets generated during the in-homogeneous mixing with subsequent ascent increase the threshold function, initiates collision-coalescence and produces drizzle drops. To the authors' knowledge, this is the first study on distinguishing and linking inhomogeneous mixing with subsequent ascent and collision-coalescence based on observational data.
