DOI: 10.1175/JCLI-D-17-0247.1
Scopus记录号: 2-s2.0-85041652716
论文题名: On the reduced North Atlantic Storminess during the last Glacial Period: The role of topography in shaping synoptic eddies
作者: Rivière G. ; Berthou S. ; Lapeyre G. ; Kageyama M.
刊名: Journal of Climate
ISSN: 8948755
出版年: 2018
卷: 31, 期: 4 起始页码: 1637
结束页码: 1652
语种: 英语
英文关键词: Atmosphere
; Climate models
; Climate variability
; General circulation models
; North Atlantic Ocean
; Storm tracks
Scopus关键词: Budget control
; Earth atmosphere
; Glacial geology
; Glaciers
; Meteorology
; Oceanography
; Potential energy
; Storms
; Topography
; Climate variability
; Dynamical interpretation
; General circulation model
; Laurentide ice sheets
; North Atlantic Ocean
; Numerical experiments
; Paleoclimate modelling
; Storm track
; Climate models
; baroclinic mode
; climate modeling
; climate variation
; eddy
; general circulation model
; heat flux
; Last Glacial Maximum
; storm track
; synoptic meteorology
; temperature gradient
; topography
; Atlantic Ocean
; Atlantic Ocean (North)
英文摘要: The North Atlantic storminess of Last Glacial Maximum (LGM) fully coupled climate simulations is generally less intense than that of their preindustrial (PI) counterparts, despite having stronger baroclinicity. An explanation for this counterintuitive result is presented by comparing two simulations of the IPSL full climate model forced by Paleoclimate Modelling Intercomparison Project Phase 3 (PMIP3) LGM and PI conditions. Two additional numerical experiments using a simplified dry general circulation model forced by idealized topography and a relaxation in temperature provide guidance for the dynamical interpretation. The forced experiment with idealized Rockies and an idealized Laurentide Ice Sheet has a less intense North Atlantic storm-track activity than the forced experiment with idealized Rockies only, despite similar baroclinicity. Both the climate and idealized runs satisfy or support the following statements. The reduced storm-track intensity can be explained by a reduced baroclinic conversion, which itself comes from a loss in eddy efficiency to tap the available potential energy as shown by energetic budgets. The eddy heat fluxes are northeastward oriented in the western Atlantic in LGM and are less well aligned with the mean temperature gradient than in PI. The southern slope of the Laurentide Ice Sheet topography forces the eddy geopotential isolines to be zonally oriented at low levels in its proximity. This distorts the tubes of constant eddy geopotential in such a way that they tilt northwestward with height during baroclinic growth in LGM while they are more optimally westward tilted in PI. © 2018 American Meteorological Society. Citation statistics:
资源类型: 期刊论文
标识符: http://119.78.100.158/handle/2HF3EXSE/111691
Appears in Collections: 气候减缓与适应
There are no files associated with this item.
作者单位: LMD/IPSL, Département de Géosciences, ENS, PSL Research University, école Polytechnique, Université Paris Saclay, Sorbonne Universités, UPMC Paris 06, CNRS, Paris, France; Met Office Hadley Centre, Exeter, United Kingdom; LSCE/IPSL, CEA-CNRS-UVSQ, Université Paris Saclay, Gif-sur-Yvette, France
Recommended Citation:
Rivière G.,Berthou S.,Lapeyre G.,et al. On the reduced North Atlantic Storminess during the last Glacial Period: The role of topography in shaping synoptic eddies[J]. Journal of Climate,2018-01-01,31(4)