气候变化领域集成服务门户(CCPortal): A Steady-State Model for the Relationship Between Humidity, Instability, and Precipitation in the Tropics

CCPortal

DOI	10.1029/2019MS001686
	A Steady-State Model for the Relationship Between Humidity, Instability, and Precipitation in the Tropics
	Singh M.S.; Warren R.A.; Jakob C.
发表日期	2019
ISSN	19422466
起始页码	3973
结束页码	3994
卷号	11 期号:12
英文摘要	A simple steady-state model for the thermodynamic structure of a convecting atmosphere under the influence of large-scale dynamics is derived based on a bulk-plume representation of convection. Given profiles of the large-scale vertical velocity and convective mass flux, the model predicts the steady-state temperature and environmental relative humidity profiles as a function of the convective entrainment rate and a parameter representing the importance of condensate reevaporation. The bulk-plume model determines the environmental relative humidity through a balance between the moistening effect of convective detrainment and the drying effect of subsidence in the cloud environment. As the convective mass flux is increased, the importance of detrainment moistening increases, leading to a higher environmental relative humidity. Since the precipitation rate also increases with the convective mass flux, this leads to a steady state in which the precipitation is a strongly increasing function of environmental relative humidity. The bulk-plume model also predicts that the atmospheric stability increases with large-scale upward motion, with the tropospheric lapse rate being most unstable under large-scale descent, when the environmental relative humidity is low. The above relationships are reproduced in a set of simulations with a cloud-system resolving model (CRM) run to equilibrium with imposed large-scale vertical velocity profiles. The results provide insight to the steady-state limit of the well-known problem of determining the relationships between large-scale conditions and the convective state of the atmosphere. ©2019. The Authors.
语种	英语
scopus关键词	Tropics; Velocity; Atmospheric stability; Cloud system-resolving models; Large scale conditions; Large-scale dynamics; Steady-state modeling; Steady-state temperature; Thermodynamic structures; Vertical velocity profiles; Atmospheric humidity; atmospheric convection; humidity; instability; numerical model; precipitation (climatology); relative humidity; simulation; steady-state equilibrium; thermodynamics; tropical environment
来源期刊	Journal of Advances in Modeling Earth Systems
文献类型	期刊论文
条目标识符	http://gcip.llas.ac.cn/handle/2XKMVOVA/156804
作者单位	School of Earth, Atmosphere & Environment, Monash University, Clayton, VIC, Australia; Centre of Excellence for Climate Extremes, Monash University, Clayton, VIC, Australia
推荐引用方式 GB/T 7714	Singh M.S.,Warren R.A.,Jakob C.. A Steady-State Model for the Relationship Between Humidity, Instability, and Precipitation in the Tropics[J],2019,11(12).
APA	Singh M.S.,Warren R.A.,&Jakob C..(2019).A Steady-State Model for the Relationship Between Humidity, Instability, and Precipitation in the Tropics.Journal of Advances in Modeling Earth Systems,11(12).
MLA	Singh M.S.,et al."A Steady-State Model for the Relationship Between Humidity, Instability, and Precipitation in the Tropics".Journal of Advances in Modeling Earth Systems 11.12(2019).