DOI: 10.1007/s00382-015-2681-3
Scopus记录号: 2-s2.0-84959102125
论文题名: Abrupt intensification of ENSO forced by deglacial ice-sheet retreat in CCSM3
作者: Lu Z. ; Liu Z. ; Zhu J.
刊名: Climate Dynamics
ISSN: 9307575
出版年: 2016
卷: 46, 期: 2017-05-06 起始页码: 1877
结束页码: 1891
语种: 英语
英文关键词: Annual cycle
; Deglacial ice-sheet forcing
; ENSO
; Frequency entrainment
英文摘要: The influence of ice-sheet retreat on the El Niño–Southern Oscillation (ENSO) variability is studied using a transient simulation in NCAR-CCSM3 forced only by variations in continental ice sheets during the last deglaciation. The most striking feature is an abrupt strengthening of ENSO (by ~25 %) at 14 thousand years before present (ka BP) in response to a significant retreat (an equivalent ~25 m sea-level rise) of the Laurentide ice sheet (LIS). This abrupt intensification of ENSO is caused mainly by a sudden weakening of the equatorial annual cycle through the nonlinear mechanism of frequency entrainment, rather than an increase in the coupled ocean–atmosphere instability. The weakened annual cycle corresponds to a reduced north–south cross-equatorial annual mean SST contrast in the eastern Pacific. This reduced interhemispheric SST gradient—significant cooling north of the equator—is forced predominantly by an anomalous easterly from an abrupt polarward shift of the jet stream in the Northern Hemisphere, which extends to the northeastern tropical Pacific Ocean surface and is reinforced by the wind-evaporation-SST feedback then propagates equatorward; it could also be contributed by a fast sea-ice expansion and a consequent cooling in the North Pacific and North Atlantic that is induced by the retreat of the LIS. © 2015, Springer-Verlag Berlin Heidelberg. 资助项目: MOST, National Natural Science Foundation of China
; NSFC, National Natural Science Foundation of China
Citation statistics:
资源类型: 期刊论文
标识符: http://119.78.100.158/handle/2HF3EXSE/53786
Appears in Collections: 过去全球变化的重建
There are no files associated with this item.
作者单位: Laboratory for Climate, Ocean and Atmosphere Studies, School of Physics, Peking University, Beijing, China; Department of Atmospheric and Oceanic Sciences and Nelson Center for Climatic Research, University of Wisconsin-Madison, Madison, WI, United States
Recommended Citation:
Lu Z.,Liu Z.,Zhu J.. Abrupt intensification of ENSO forced by deglacial ice-sheet retreat in CCSM3[J]. Climate Dynamics,2016-01-01,46(2017-05-06)