DOI: 10.1007/s00382-010-0972-2
Scopus记录号: 2-s2.0-84855254358
论文题名: A bulk mass flux convection scheme for climate model: Description and moisture sensitivity
作者: Kim D. ; Kang I.-S.
刊名: Climate Dynamics
ISSN: 9307575
出版年: 2012
卷: 38, 期: 2017-01-02 起始页码: 411
结束页码: 429
语种: 英语
英文关键词: Cumulus parameterization
; General circulation model
; Moisture sensitivity
英文摘要: A convection scheme for climate model is developed based on Tiedtke's (Mon Weather Rev 117:1779-1800, 1989) bulk mass flux framework and is evaluated with observational data and cloud resolving model simulation data. The main differences between the present parameterization and Tiedtke's parameterization are the convection trigger, fractional entrainment and detrainment rate formulations, and closure method. Convection is triggered if the vertical velocity of a rising parcel is positive at the level at which the parcel is saturated. The fractional entrainment rate depends on the vertical velocity and buoyancy of the parcel as well as the environmental relative humidity. For the fractional detrainment rate, a linear decrease in the updraft mass flux above maximum buoyancy level is assumed. In the closure method, the cloud base mass flux is determined by considering both cloud layer instability and subcloud layer turbulent kinetic energy as controlling factors in the strength of the convection. The convection scheme is examined in a single column framework as well as using a general circulation model. The present bulk mass flux (BMF) scheme is compared with a simplified Relaxed Arakawa-Schubert (RAS) scheme. In contrast to the RAS, which specifies the cloud top, cloud top height in BMF depends on environmental properties, by considering the conditions of both the parcel and its environment in a fractional entrainment and detrainment rate formulations. As a result, BMF shows improved sensitivity in depth and strength of convection on environmental humidity compared to RAS, by strengthening coupling between cloud and environment. When the mid to lower troposphere is dry, the cloud resolving model and BMF produce cloud top around the dry layer and moisten the layer. In the framework of general circulation model, enhanced coupling between convection and environmental humidity in BMF results in improved representation of eastward propagating intraseasonal variability in the tropics-the Madden-Julian oscillation. © 2011 Springer-Verlag. Citation statistics:
资源类型: 期刊论文
标识符: http://119.78.100.158/handle/2HF3EXSE/55400
Appears in Collections: 过去全球变化的重建
There are no files associated with this item.
作者单位: School of Earth and Environmental Sciences, Seoul National University, Seoul 151-747, South Korea; Lamont-Doherty Earth Observatory of Columbia University, Palisades, NY 10964-1000, United States
Recommended Citation:
Kim D.,Kang I.-S.. A bulk mass flux convection scheme for climate model: Description and moisture sensitivity[J]. Climate Dynamics,2012-01-01,38(2017-01-02)