DOI: 10.1007/s00382-017-3712-z
Scopus记录号: 2-s2.0-85018735333
论文题名: Simulated precipitation diurnal cycles over East Asia using different CAPE-based convective closure schemes in WRF model
作者: Yang B. ; Zhou Y. ; Zhang Y. ; Huang A. ; Qian Y. ; Zhang L.
刊名: Climate Dynamics
ISSN: 9307575
出版年: 2018
卷: 50, 期: 2018-05-06 起始页码: 1639
结束页码: 1658
语种: 英语
英文关键词: Boundary-layer resolution
; Convective closure
; East Asia
; Precipitation diurnal cycle simulation
; WRF model
Scopus关键词: boundary layer
; computer simulation
; convective system
; diurnal variation
; numerical model
; potential energy
; precipitation (climatology)
; troposphere
; weather forecasting
; Far East
英文摘要: Closure assumption in convection parameterization is critical for reasonably modeling the precipitation diurnal variation in climate models. This study evaluates the precipitation diurnal cycles over East Asia during the summer of 2008 simulated with three convective available potential energy (CAPE) based closure assumptions, i.e. CAPE-relaxing (CR), quasi-equilibrium (QE), and free-troposphere QE (FTQE) and investigates the impacts of planetary boundary layer (PBL) mixing, advection, and radiation on the simulation by using the weather research and forecasting model. The sensitivity of precipitation diurnal cycle to PBL vertical resolution is also examined. Results show that the precipitation diurnal cycles simulated with different closures all exhibit large biases over land and the simulation with FTQE closure agrees best with observation. In the simulation with QE closure, the intensified PBL mixing after sunrise is responsible for the late-morning peak of convective precipitation, while in the simulation with FTQE closure, convective precipitation is mainly controlled by advection cooling. The relative contributions of different processes to precipitation formation are functions of rainfall intensity. In the simulation with CR closure, the dynamical equilibrium in the free troposphere still can be reached, implying the complex cause-effect relationship between atmospheric motion and convection. For simulations in which total CAPE is consumed for the closures, daytime precipitation decreases with increased PBL resolution because thinner model layer produces lower convection starting layer, leading to stronger downdraft cooling and CAPE consumption. The sensitivity of the diurnal peak time of precipitation to closure assumption can also be modulated by changes in PBL vertical resolution. The results of this study help us better understand the impacts of various processes on the precipitation diurnal cycle simulation. © 2017, Springer-Verlag Berlin Heidelberg. Citation statistics:
资源类型: 期刊论文
标识符: http://119.78.100.158/handle/2HF3EXSE/109434
Appears in Collections: 影响、适应和脆弱性 气候变化事实与影响
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作者单位: CMA-NJU Joint Laboratory for Climate Prediction Studies, Institute for Climate and Global Change Research, School of Atmospheric Sciences, Nanjing University, Nanjing, China; Collaborative Innovation Center of Climate Change, Nanjing, Jiangsu, China; Pacific Northwest National Laboratory, Richland, WA, United States
Recommended Citation:
Yang B.,Zhou Y.,Zhang Y.,et al. Simulated precipitation diurnal cycles over East Asia using different CAPE-based convective closure schemes in WRF model[J]. Climate Dynamics,2018-01-01,50(2018-05-06)