DOI: 10.1016/j.quascirev.2016.01.022
Scopus记录号: 2-s2.0-84956897700
论文题名: δ18O and salinity variability from the Last Glacial Maximum to Recent in the Bay of Bengal and Andaman Sea
作者: Sijinkumar A.V. ; Clemens S. ; Nath B.N. ; Prell W. ; Benshila R. ; Lengaigne M.
刊名: Quaternary Science Reviews
ISSN: 2773791
出版年: 2016
卷: 135 起始页码: 79
结束页码: 91
语种: 英语
英文关键词: Andaman Sea
; Bay of Bengal
; Late Quaternary
; Oxygen isotope
; Salinity gradient
; Stratification
; Summer monsoon
Scopus关键词: Buildings
; Glacial geology
; Housing
; Isotopes
; Sea level
; Stream flow
; Thermal stratification
; Andaman Sea
; Bay of Bengal
; Late quaternary
; Oxygen isotopes
; Salinity gradients
; Summer monsoon
; Surface waters
; deglaciation
; foraminifera
; Holocene
; Last Glacial Maximum
; mixing ratio
; monsoon
; outflow
; oxygen isotope
; paleosalinity
; precipitation (climatology)
; runoff
; salinity
; sensitivity analysis
; stratification
; summer
; thermocline
; Younger Dryas
; Andaman Sea
; Bay of Bengal
; Indian Ocean
; Foraminifera
英文摘要: Oxygen isotopes of surface, thermocline and bottom dwelling foraminifera were analysed from two well-dated Andaman Sea cores and combined with nine previously published records from the Bay of Bengal (BoB) and Andaman Sea to create a transect spanning 20°N to 5°N. Combined with temperature estimates and the observed seawater δ18O-salinity relationship, these data are used to estimate past changes in BoB salinity structure. Compared to modern, mid-Holocene (9-6 cal ka BP) surface waters in the northern BoB were 2.5 psμ (8%) fresher, Andaman Sea were 3.8 psμ (12%) fresher, and southern BoB were 1.2 psμ (3.5%) fresher. Conversely, during the last glacial maximum (LGM), surface waters in the northern BoB were 2.9 psμ (9%) more saline while Andaman Sea were essentially unchanged and southern BoB were 1.7 psμ (4.9%) more saline compared to modern. The relative freshness of the Andaman during the last glacial maximum is likely the result of basin morphology during sea level low stand, resulting in reduced surface water mixing with the open BoB as well as shelf emergence, causing increased proximity of the core locations to river outflow. Sensitivity experiments using a regional ocean model indicate that the increased mid-Holocene north to south (20°N to 5°N) salinity gradient can be achieved with a ~50% increase in precipitation/runoff while the decreased glacial age gradient can be achieved with a ~50% reduction in precipitation/runoff. During the deglaciation, both surface and thermocline-dwelling species in the Andaman and northern BoB exhibit depleted δ18O within the Younger Dryas (YD), indicating colder and/or more saline conditions. None of the records from the southern BoB site have clear YD structure, possibly due to the combined effects of bioturbation and low sedimentation rates. © 2016 Elsevier Ltd. Citation statistics:
资源类型: 期刊论文
标识符: http://119.78.100.158/handle/2HF3EXSE/59676
Appears in Collections: 过去全球变化的重建
There are no files associated with this item.
作者单位: Earth, Environmental and Planetary Sciences, Brown University, Providence, RI, United States; CSIR-National Institute of Oceanography, Dona Paula, Goa, India; CNRS/LEGOS, Toulouse, France; LOCEAN, IPSL, Sorbonne Universités (UPMC, Univ. Paris 06)/CNRS/IRD/MNHN, Paris, France; Indo-French Cell for Water Sciences, IISc-NIO-IITM-IRD Joint International Laboratory, NIO, Goa, India
Recommended Citation:
Sijinkumar A.V.,Clemens S.,Nath B.N.,et al. δ18O and salinity variability from the Last Glacial Maximum to Recent in the Bay of Bengal and Andaman Sea[J]. Quaternary Science Reviews,2016-01-01,135