DOI: 10.1016/j.quascirev.2013.12.006
Scopus记录号: 2-s2.0-84891453089
论文题名: Modelling stable water isotopes in monsoon precipitation during the previous interglacial
作者: Sjolte J. ; Hoffmann G.
刊名: Quaternary Science Reviews
ISSN: 2773791
出版年: 2014
卷: 85 起始页码: 119
结束页码: 135
语种: 英语
英文关键词: Eemian interglacial
; Modelling
; Monsoon
; Stable water isotopes
Scopus关键词: Eemian interglacial
; General circulation model
; Indian summer monsoon
; Intertropical convergence zone
; Monsoon
; Monsoon precipitation
; Northern Hemispheres
; Stable water isotopes
; Atmospheric thermodynamics
; Models
; Tropics
; Isotopes
; climate conditions
; dating method
; Eemian
; general circulation model
; hydrological cycle
; interglacial
; monsoon
; Northern Hemisphere
; numerical model
; oxygen isotope
; precipitation (climatology)
; proxy climate record
; speleothem
; stable isotope
; India
英文摘要: Changes in the tropical hydrological cycle have been recorded world wide in speleothem records dating back more than 200,000 years for some areas. Numerous empirical and modelling studies have demonstrated a strong link between the intensity of the northern hemisphere monsoon and the precessional insolation cycle (~23ka (thousand years)). Here we present simulations of the climate conditions of the previous interglacial, the Eemian (115-130ka BP), using a general circulation model. We focus on changes in the tropical hydrological cycle and in the monsoon in particular. The model is equipped with a module for computing the water isotopic composition of all water reservoirs represented by the model. Our analysis of the simulated water isotope signals indicates that this key palaeo-proxy, i.e. the 18O or Deuterium signal in precipitation, is controlled by varying factors in different tropical areas: The main control on 18O for the Indian summer monsoon is the local precipitation amount, in accordance with the traditional interpretation, while the main control of 18O for East Asia is downwind depletion of 18O in vapour along the transport path. Over Africa the model simulates a strong gradient in the 18O anomalies during the Eemian climatic optimum, with depleted values in the east and relatively enriched 18O content in the west. This pattern is the result of a combination of the local "amount effect" and an anomalous zonal moisture transport. The influence of the SSTs anomalies on the placement of the Intertropical Convergence Zone (ITCZ) is found to be of major importance for the precipitation amount in the coastal regions of tropical South America. For the western part of South America a decrease in precipitation is seen for the Eemian climatic optimum, while an increase is seen for the eastern part. Our results underline the importance of reviewing the mechanisms causing isotopic changes in proxy records and further investigating the causes for past shifts in the ITCZ. © 2013 Elsevier Ltd. Citation statistics:
资源类型: 期刊论文
标识符: http://119.78.100.158/handle/2HF3EXSE/60393
Appears in Collections: 过去全球变化的重建
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作者单位: Centre for Ice and Climate, Niels Bohr Institute, University of Copenhagen, Juliane Maries Vej 30, DK-2100 Copenhagen, OE, Denmark; Department of Geology, Lunds University, Sölvegatan 12, 22362 Lund, Sweden; Laboratoire des Science du Climat et de l'Environnement CEA-CNRS-UVSQ-IPSL, Saclay, France; Institute for Marine and Atmospheric research Utrecht (IMAU), Utrecht University, Netherlands
Recommended Citation:
Sjolte J.,Hoffmann G.. Modelling stable water isotopes in monsoon precipitation during the previous interglacial[J]. Quaternary Science Reviews,2014-01-01,85