DOI: 10.1016/j.quascirev.2012.12.008
Scopus记录号: 2-s2.0-84873251391
论文题名: Southern Hemisphere westerly wind changes during the Last Glacial Maximum: Model-data comparison
作者: Sime L.C. ; Kohfeld K.E. ; Le Quéré C. ; Wolff E.W. ; de Boer A.M. ; Graham R.M. ; Bopp L.
刊名: Quaternary Science Reviews
ISSN: 2773791
出版年: 2013
卷: 64 起始页码: 104
结束页码: 120
语种: 英语
英文关键词: Atmospheric modelling
; Data-model comparison
; Glacial-interglacial cycles
; LGM
; PMIP2
; Southern Ocean
; Westerly winds
Scopus关键词: Atmospheric modelling
; Glacial-interglacial cycles
; LGM
; PMIP2
; Southern ocean
; Westerly winds
; Atmospheric temperature
; Boundary conditions
; Carbon dioxide
; Data structures
; Glacial geology
; Moisture
; Oceanography
; Salinity measurement
; Wind
; Computer simulation
; atmospheric modeling
; carbon dioxide
; climate modeling
; comparative study
; glacial-interglacial cycle
; global ocean
; Last Glacial
; Last Glacial Maximum
; moisture content
; oceanic circulation
; paleoatmosphere
; paleoceanography
; precipitation (climatology)
; Southern Hemisphere
; westerly
; wind profile
; Southern Ocean
英文摘要: The Southern Hemisphere (SH) westerly winds are thought to be critical to global ocean circulation, productivity, and carbon storage. For example, an equatorward shift in the winds, though its affect on the Southern Ocean circulation, has been suggested as the leading cause for the reduction in atmospheric CO2 during the Last Glacial period. Despite the importance of the winds, it is currently not clear, from observations or model results, how they behave during the Last Glacial. Here, an atmospheric modelling study is performed to help determine likely changes in the SH westerly winds during the Last Glacial Maximum (LGM). Using LGM boundary conditions, the maximum in SH westerlies is strengthened by ~+1 m s-1 and moved southward by ~2° at the 850 hPa pressure level. Boundary layer stabilisation effects over equatorward extended LGM sea-ice can lead to a small apparent equatorward shift in the wind band at the surface. Further sensitivity analysis with individual boundary condition changes indicate that changes in sea surface temperatures are the strongest factor behind the wind change. The HadAM3 atmospheric simulations, along with published PMIP2 coupled climate model simulations, are then assessed against the newly synthesised database of moisture observations for the LGM. Although the moisture data is the most commonly cited evidence in support of a large equatorward shift in the SH winds during the LGM, none of the models that produce realistic LGM precipitation changes show such a large equatorward shift. In fact, the model which best simulates the moisture proxy data is the HadAM3 LGM simulation which shows a small poleward wind shift. While we cannot prove here that a large equatorward shift would not be able to reproduce the moisture data as well, we show that the moisture proxies do not provide an observational evidence base for it. © 2012 Elsevier Ltd. Citation statistics:
资源类型: 期刊论文
标识符: http://119.78.100.158/handle/2HF3EXSE/60697
Appears in Collections: 过去全球变化的重建
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作者单位: British Antarctic Survey, Ice Cores, Cambridge CB3 0ET, United Kingdom; Simon Fraser University, 8888 University Drive, Burnaby V5A 1S6, Canada; School of Environmental Sciences, University of East Anglia, Norwich NR4 7TJ, United Kingdom; Department of Geological Sciences, Stockholm University, 106 91 Stockholm, Sweden; Centre National de la Recherche Scientifique, CEA, Saclay 91191, France
Recommended Citation:
Sime L.C.,Kohfeld K.E.,Le Quéré C.,et al. Southern Hemisphere westerly wind changes during the Last Glacial Maximum: Model-data comparison[J]. Quaternary Science Reviews,2013-01-01,64