DOI: 10.1007/s00382-017-3909-1
Scopus记录号: 2-s2.0-85029511182
论文题名: Regional and seasonal variations of the double-ITCZ bias in CMIP5 models
作者: Adam O. ; Schneider T. ; Brient F.
刊名: Climate Dynamics
ISSN: 9307575
出版年: 2018
卷: 51, 期: 2018-01-02 起始页码: 101
结束页码: 117
语种: 英语
英文关键词: Atmospheric energy budget
; CMIP5 models
; Double-ITCZ bias
; ITCZ
英文摘要: Current climate models represent the zonal- and annual-mean intertropical convergence zone (ITCZ) position in a biased way, with an unrealistic double precipitation peak straddling the equator in the ensemble mean over the models. This bias is seasonally and regionally localized. It results primarily from two regions: the eastern Pacific and Atlantic (EPA), where the ITCZ in boreal winter and spring is displaced farther south than is observed; and the western Pacific (WP), where a more pronounced and wider than observed double ITCZ straddles the equator year-round. Additionally, the precipitation associated with the ascending branches of the zonal overturning circulations (e.g., Walker circulation) in the Pacific and Atlantic sectors is shifted westward. We interpret these biases in light of recent theories that relate the ITCZ position to the atmospheric energy budget. WP biases are associated with the well known Pacific cold tongue bias, which, in turn, is linked to atmospheric net energy input biases near the equator. In contrast, EPA biases are shown to be associated with a positive bias in the cross-equatorial divergent atmospheric energy transport during boreal winter and spring, with two potential sources: tropical biases associated with equatorial sea surface temperatures (SSTs) and tropical low clouds, and extratropical biases associated with Southern Ocean clouds and north Atlantic SST. The distinct seasonal and regional characteristics of WP and EPA biases and the differences in their associated energy budget biases suggest that the biases in the two sectors involve different mechanisms and potentially different sources. © 2017, Springer-Verlag GmbH Germany. Citation statistics:
资源类型: 期刊论文
标识符: http://119.78.100.158/handle/2HF3EXSE/109241
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: Hebrew University of Jerusalem, Jerusalem, Israel; ETH Zürich, Zürich, Switzerland; California Institute of Technology, Pasadena, CA, United States; Centre National de Recherches Météorologiques, Météo-France/CNRS, Toulouse, France
Recommended Citation:
Adam O.,Schneider T.,Brient F.. Regional and seasonal variations of the double-ITCZ bias in CMIP5 models[J]. Climate Dynamics,2018-01-01,51(2018-01-02)