DOI: 10.1007/s00382-017-4016-z
Scopus记录号: 2-s2.0-85038349960
论文题名: The impacts of oceanic deep temperature perturbations in the North Atlantic on decadal climate variability and predictability
作者: Germe A. ; Sévellec F. ; Mignot J. ; Fedorov A. ; Nguyen S. ; Swingedouw D.
刊名: Climate Dynamics
ISSN: 9307575
出版年: 2018
卷: 51, 期: 2018-05-06 起始页码: 2341
结束页码: 2357
语种: 英语
英文关键词: Atlantic meridional overturning circulation
; Decadal climate predictability
; Initial condition uncertainties
; IPSL-CM5A
; Linear optimal perturbations
; North Atlantic variability
Scopus关键词: climate prediction
; climate variation
; decadal variation
; meridional circulation
; overturn
; perturbation
; sea surface temperature
; temperature anomaly
; uncertainty analysis
; Atlantic Ocean
; Atlantic Ocean (North)
; North America
; Sahel [Sub-Saharan Africa]
英文摘要: Decadal climate predictability in the North Atlantic is largely related to ocean low frequency variability, whose sensitivity to initial conditions is not very well understood. Recently, three-dimensional oceanic temperature anomalies optimally perturbing the North Atlantic Mean Temperature (NAMT) have been computed via an optimization procedure using a linear adjoint to a realistic ocean general circulation model. The spatial pattern of the identified perturbations, localized in the North Atlantic, has the largest magnitude between 1000 and 4000 m depth. In the present study, the impacts of these perturbations on NAMT, on the Atlantic meridional overturning circulation (AMOC), and on climate in general are investigated in a global coupled model that uses the same ocean model as was used to compute the three-dimensional optimal perturbations. In the coupled model, these perturbations induce AMOC and NAMT anomalies peaking after 5 and 10 years, respectively, generally consistent with the ocean-only linear predictions. To further understand their impact, their magnitude was varied in a broad range. For initial perturbations with a magnitude comparable to the internal variability of the coupled model, the model response exhibits a strong signature in sea surface temperature and precipitation over North America and the Sahel region. The existence and impacts of these ocean perturbations have important implications for decadal prediction: they can be seen either as a source of predictability or uncertainty, depending on whether the current observing system can detect them or not. In fact, comparing the magnitude of the imposed perturbations with the uncertainty of available ocean observations such as Argo data or ocean state estimates suggests that only the largest perturbations used in this study could be detectable. This highlights the importance for decadal climate prediction of accurate ocean density initialisation in the North Atlantic at intermediate and greater depths. © 2017, The Author(s). Citation statistics:
资源类型: 期刊论文
标识符: http://119.78.100.158/handle/2HF3EXSE/109156
Appears in Collections: 影响、适应和脆弱性 气候变化事实与影响
There are no files associated with this item.
作者单位: National Oceanography Centre, Water Front Campus, European Way, Southampton, SO14 3ZH, United Kingdom; Ocean and Earth Science, University of Southampton, Southampton, United Kingdom; LOCEAN Laboratory-IPSL, Sorbonne Universités (UPMC, Univ Paris 06)-CNRS-IRD-MNHN, 4 place Jussieu, Paris, 75005, France; Department of Geology and Geophysics, Yale University, New Haven, CT, United States; Environnements et Paléoenvironnements Océaniques et Continentaux (EPOC), UMR CNRS 5805 EPOC-OASU-Université de Bordeaux, Allée Geoffroy Saint-Hilaire, Pessac, 33615, France
Recommended Citation:
Germe A.,Sévellec F.,Mignot J.,et al. The impacts of oceanic deep temperature perturbations in the North Atlantic on decadal climate variability and predictability[J]. Climate Dynamics,2018-01-01,51(2018-05-06)