DOI: 10.1175/JCLI-D-11-00178.1
Scopus记录号: 2-s2.0-84865189118
论文题名: The role of atmosphere feedbacks during ENSO in the CMIP3 models. Part III: The shortwave flux feedback
作者: Lloyd J. ; Guilyardi E. ; Weller H.
刊名: Journal of Climate
ISSN: 8948755
出版年: 2012
卷: 25, 期: 12 起始页码: 4275
结束页码: 4293
语种: 英语
Scopus关键词: Atmosphere models
; Atmospheric response
; Cloud cover
; Coupled general circulation models
; Coupled Model Intercomparison Project
; Decomposition methods
; Dynamical response
; Eastern equatorial Pacific
; Non-Linearity
; Physical mechanism
; Sea surface temperatures
; SST anomalies
; Atmospheric pressure
; Damping
; Dynamics
; Errors
; Feedback
; Nickel compounds
; Computer simulation
; atmospheric modeling
; climate feedback
; computer simulation
; El Nino-Southern Oscillation
; general circulation model
; sea surface temperature
; shortwave radiation
; temperature anomaly
英文摘要: Previous studies using coupled general circulation models (GCMs) suggest that the atmosphere model plays a dominant role in the modeled El Niño-Southern Oscillation (ENSO), and that intermodel differences in the thermodynamical damping of sea surface temperatures (SSTs) are a dominant contributor to the ENSO amplitude diversity. This study presents a detailed analysis of the shortwave flux feedback (α SW)in12 Coupled Model Intercomparison Project phase 3 (CMIP3) simulations, motivated by findings that α SW is the primary contributor to model thermodynamical damping errors. A "feedback decomposition method," developed to elucidate the α SW biases, shows that all models un-derestimate the dynamical atmospheric response to SSTs in the eastern equatorial Pacific, leading to un-derestimated α SW values. Biases in the cloud response to dynamics and the shortwave interception by clouds also contribute to errors in α SW. Changes in the α SW feedback between the coupled and corresponding atmosphere-only simulations are related to changes in the mean dynamics. A large nonlinearity is found in the observed and modeled SW flux feedback, hidden when linearly cal-culating α SW. In the observations, two physical mechanisms are proposed to explain this nonlinearity: 1) a weaker subsidence response to cold SST anomalies than the ascent response to warm SST anomalies and 2) a nonlinear high-level cloud cover response to SST. The shortwave flux feedback nonlinearity tends to be underestimated by the models, linked to an underestimated nonlinearity in the dynamical response to SST. The process-based methodology presented in this study may help to correct model ENSO atmospheric biases, ultimately leading to an improved simulation of ENSO in GCMs. © 2012 American Meteorological Society. Citation statistics:
资源类型: 期刊论文
标识符: http://119.78.100.158/handle/2HF3EXSE/52383
Appears in Collections: 气候变化事实与影响
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作者单位: Department of Meteorology, University of Reading, Reading, United Kingdom; LOCEAN/IPSL, Paris, France; NCAS-Climate, Department of Meteorology, University of Reading, Reading, United Kingdom
Recommended Citation:
Lloyd J.,Guilyardi E.,Weller H.. The role of atmosphere feedbacks during ENSO in the CMIP3 models. Part III: The shortwave flux feedback[J]. Journal of Climate,2012-01-01,25(12)