DOI: 10.1175/JCLI-D-15-0897.1
Scopus记录号: 2-s2.0-84983522067
论文题名: Constraints on climate sensitivity from space-based measurements of low-cloud reflection
作者: Brient F. ; Schneider T.
刊名: Journal of Climate
ISSN: 8948755
出版年: 2016
卷: 29, 期: 16 起始页码: 5821
结束页码: 5835
语种: 英语
Scopus关键词: Global warming
; Greenhouse gases
; Information theory
; Sensitivity analysis
; Climate sensitivity
; Confidence levels
; Gas concentration
; Historical simulation
; Interannual time scale
; Short-wave radiation
; Temporal variation
; Underlying surface
; Climate models
英文摘要: Physical uncertainties in global-warming projections are dominated by uncertainties about how the fraction of incoming shortwave radiation that clouds reflect will change as greenhouse gas concentrations rise. Differences in the shortwave reflection by low clouds over tropical oceans alone account for more than half of the variance of the equilibrium climate sensitivity (ECS) among climate models, which ranges from 2.1 to 4.7 K. Space-based measurements now provide an opportunity to assess how well models reproduce temporal variations of this shortwave reflection on seasonal to interannual time scales. Here such space-based measurements are used to show that shortwave reflection by low clouds over tropical oceans decreases robustly when the underlying surface warms, for example, by -(0.96 ± 0.22)%K-1 (90% confidence level) for deseasonalized variations. Additionally, the temporal covariance of low-cloud reflection with temperature in historical simulations with current climate models correlates strongly (r = -0.67) with the models' ECS. Therefore, measurements of temporal low-cloud variations can be used to constrain ECS estimates based on climate models. An information-theoretic weighting of climate models by how well they reproduce the measured deseasonalized covariance of shortwave cloud reflection with temperature yields a most likely ECS estimate around 4.0 K; an ECS below 2.3 K becomes very unlikely (90% confidence). © 2016 American Meteorological Society. 资助项目: SNF, Swiss National Science Foundation
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资源类型: 期刊论文
标识符: http://119.78.100.158/handle/2HF3EXSE/50033
Appears in Collections: 气候变化事实与影响
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作者单位: Department of Earth Sciences, ETH Zürich, Zürich, Switzerland; Department of Earth Sciences, ETH Zürich, Zürich, Switzerland; California Institute of Technology, Pasadena, CA, United States
Recommended Citation:
Brient F.,Schneider T.. Constraints on climate sensitivity from space-based measurements of low-cloud reflection[J]. Journal of Climate,2016-01-01,29(16)