DOI: 10.1175/JCLI-D-12-00442.1
Scopus记录号: 2-s2.0-84881247845
论文题名: Precipitation partitioning, tropical clouds, and intraseasonal variability in GFDL AM2
作者: Lin Y. ; Zhao M. ; Ming Y. ; Golaz J.-C. ; Donner L.J. ; Klein S.A. ; Ramaswamy V. ; Xie S.
刊名: Journal of Climate
ISSN: 8948755
出版年: 2013
卷: 26, 期: 15 起始页码: 5453
结束页码: 5466
语种: 英语
Scopus关键词: Convective parameterization
; Geophysical fluid dynamics laboratories
; Intraseasonal variability
; Large-scale precipitation
; Moisture-convection feedback
; Precipitation characteristics
; Precipitation variability
; Tropical intraseasonal variability
; Climate models
; Computer simulation
; Natural convection
; Tropics
; Precipitation (meteorology)
; atmospheric moisture
; climate modeling
; cloud cover
; computer simulation
; convective system
; cumulus
; heat flux
; parameterization
; partitioning
; precipitation (climatology)
; seasonal variation
; stratification
; troposphere
英文摘要: A set of Geophysical Fluid Dynamics Laboratory (GFDL) Atmospheric Model version 2 (AM2) sensitivity simulations by varying an entrainment threshold rate to control deep convection occurrence are used to investigate how cumulus parameterization impacts tropical cloud and precipitation characteristics. In the tropics, model convective precipitation (CP) is frequent and light, while large-scale precipitation (LSP) is intermittent and strong. With deep convection inhibited, CP decreases significantly over land and LSP increases prominently over ocean. This results in an overall redistribution of precipitation from land to ocean. A composite analysis reveals that cloud fraction (low and middle) and cloud condensate associated with LSP are substantially larger than those associated with CP. With about the same total precipitation and precipitation frequency distribution over the tropics, simulations having greater LSP fraction tend to have larger cloud condensate and low and middle cloud fraction. Simulations having a greater LSP fraction tend to be drier and colder in the upper troposphere. The induced unstable stratification supports strong transient wind perturbations and LSP. Greater LSP also contributes to greater intraseasonal (20-100 days) precipitation variability. Model LSP has a close connection to the low-level convergence via the resolved grid-scale dynamics and, thus, a close coupling with the surface heat flux. Such wind-evaporation feedback is essential to the development and maintenance of LSP and enhances model precipitation variability. LSP has stronger dependence and sensitivity on column moisture than CP. The moisture-convection feedback, critical to tropical intraseasonal variability, is enhanced in simulations with large LSP. Strong precipitation variability accompanied by a worse mean state implies that an optimal precipitation partitioning is critical to model tropical climate simulation. © 2013 American Meteorological Society. Citation statistics:
资源类型: 期刊论文
标识符: http://119.78.100.158/handle/2HF3EXSE/51744
Appears in Collections: 气候变化事实与影响
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作者单位: University Corporation for Atmospheric Research, Boulder, CO, United States; NOAA/Geophysical Fluid Dynamics Laboratory, Princeton, NJ, United States; Lawrence Livermore National Laboratory, Livermore, CA, United States
Recommended Citation:
Lin Y.,Zhao M.,Ming Y.,et al. Precipitation partitioning, tropical clouds, and intraseasonal variability in GFDL AM2[J]. Journal of Climate,2013-01-01,26(15)