DOI: 10.1175/JCLI-D-16-0745.1
Scopus记录号: 2-s2.0-85028505706
论文题名: The effect of cloud cover on the meridional heat transport: Lessons from variable rotation experiments
作者: Liu X. ; Battisti D.S. ; Roe G.H.
刊名: Journal of Climate
ISSN: 8948755
出版年: 2017
卷: 30, 期: 18 起始页码: 7465
结束页码: 7479
语种: 英语
Scopus关键词: Atmospheric movements
; Clouds
; Heat transfer
; Tropics
; Atmospheric circulation
; Eddies
; Energy transport
; Hadley circulation
; Meridional gradients
; Meridional heat transports
; Outgoing longwave radiation
; Tropical temperatures
; Rotation
英文摘要: The question "What determines the meridional heat transport (MHT)?" is explored by performing a series of rotation-rate experiments with an aquaplanetGCMcoupled to a slab ocean. The change of meridional heat transport with rotation rate falls into two regimes: in a "slow rotating" regime (rotation rate < 1/2 modern rotation) MHT decreases with increasing rotation rate, whereas in a "fast rotating" regime (rotation rate ≥ 1/2 modern rotation) MHT is nearly invariant. The two-regime feature of MHT is primarily related to the reduction in tropical clouds and increase in tropical temperature that are associated with the narrowing and weakening of the Hadley cell with increasing rotation rate. In the slow-rotating regime, the Hadley cell contracts and weakens as rotation rate is increased; the resulting warming causes a local increase in outgoing longwave radiation (OLR), which consequently decreases MHT. In the fast-rotating regime, the Hadley cell continues to contract as rotation rate is increased, resulting in a decrease in tropical and subtropical clouds that increases the local absorbed shortwave radiation (ASR) by an amount that almost exactly compensates the local increases in OLR. In the fast-rotating regime, the model heat transport is approximately diffusive, with an effective eddy diffusivity that is consistent with eddy mixing-length theory. The effective eddy diffusivity decreases with increasing rotation rate. However, this decrease is nearly offset by a strong increase in the meridional gradient of moist static energy and hence results in a near-constancy of MHT. The results herein extend previous work on the MHT by highlighting that the spatial patterns of clouds and the factors that influence them are leading controls on MHT. © 2017 American Meteorological Society. Citation statistics:
资源类型: 期刊论文
标识符: http://119.78.100.158/handle/2HF3EXSE/48717
Appears in Collections: 气候减缓与适应 气候变化与战略
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作者单位: Department of Atmospheric Sciences, University of Washington, Seattle, WA, United States; Department of Earth and Space Sciences, University of Washington, Seattle, WA, United States
Recommended Citation:
Liu X.,Battisti D.S.,Roe G.H.. The effect of cloud cover on the meridional heat transport: Lessons from variable rotation experiments[J]. Journal of Climate,2017-01-01,30(18)