DOI: 10.1175/JCLI-D-16-0525.1
Scopus记录号: 2-s2.0-85008219812
论文题名: The influences of the Atlantic multidecadal oscillation on the mean strength of the North Pacific subtropical high during boreal winter
作者: Lyu K. ; Yu J.-Y. ; Paek H.
刊名: Journal of Climate
ISSN: 8948755
出版年: 2017
卷: 30, 期: 1 起始页码: 411
结束页码: 426
语种: 英语
Scopus关键词: Earth atmosphere
; Mechanical waves
; Oceanography
; Sea level
; Subsidence
; Multidecadal variability
; North Atlantic Ocean
; North Pacific Ocean
; Stationary waves
; Vertical motions
; Walker circulation
; Tropics
; Pomatiopsis californica
英文摘要: The Atlantic multidecadal oscillation (AMO) has been shown to be capable of exerting significant influences on the Pacific climate. In this study, the authors analyze reanalysis datasets and conduct forced and coupled experiments with an atmospheric general circulation model (AGCM) to explain why the winter North Pacific subtropical high strengthens and expands northwestward during the positive phase of the AMO. The results show that the tropical Atlantic warming associated with the positive AMO phase leads to a westward displacement of the Pacific Walker circulation and a cooling of the tropical Pacific Ocean, thereby inducing anomalous descending motion over the central tropical Pacific. The descending motion then excites a stationary Rossby wave pattern that extends northward to produce a nearly barotropic anticyclone over the North Pacific. A diagnosis based on the quasigeostrophic vertical velocity equation reveals that the stationary wave pattern also results in enhanced subsidence over the northeastern Pacific via the anomalous advections of vorticity and temperature. The anomalous barotropic anticyclone and the enhanced subsidence are the two mechanisms that increase the sea level pressure over the North Pacific. The latter mechanism occurs to the southeast of the former one and thus is more influential in the subtropical high region. Both mechanisms can be produced in forced and coupled AGCMs but are displaced northward as a result of stationary wave patterns that differ from those observed. This explains why the model-simulated North Pacific sea level pressure responses to the AMO tend to be biased northward. © 2017 American Meteorological Society.
资助项目: NSF, National Science Foundation
; NSF, National Science Foundation
Citation statistics:
资源类型: 期刊论文
标识符: http://119.78.100.158/handle/2HF3EXSE/49779
Appears in Collections: 气候变化事实与影响
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作者单位: Department of Earth System Science, University of California, Irvine, Irvine, CA, United States
Recommended Citation:
Lyu K.,Yu J.-Y.,Paek H.. The influences of the Atlantic multidecadal oscillation on the mean strength of the North Pacific subtropical high during boreal winter[J]. Journal of Climate,2017-01-01,30(1)