DOI: 10.1016/j.quascirev.2016.04.011
Scopus记录号: 2-s2.0-84969799160
论文题名: Post-glacial variability of sea ice cover, river run-off and biological production in the western Laptev Sea (Arctic Ocean) - A high-resolution biomarker study
作者: Hörner T. ; Stein R. ; Fahl K. ; Birgel D.
刊名: Quaternary Science Reviews
ISSN: 2773791
出版年: 2016
卷: 143 起始页码: 133
结束页码: 149
语种: 英语
英文关键词: Arctic Ocean
; Biomarker
; IP25
; Laptev Sea
; Paleoclimate
; River run-off
; Sea ice
Scopus关键词: Biogeochemistry
; Biological materials
; Biomarkers
; Glacial geology
; Organic compounds
; Phytoplankton
; Rivers
; Sea ice
; Sea level
; Solar energy
; Arctic ocean
; Atmospheric circulation changes
; Biological production
; IP25
; Laptev Sea
; Paleoclimates
; Sea level condition
; Temporal resolution
; Ice
; atmospheric circulation
; biological production
; biomarker
; ice cover
; marine environment
; paleoclimate
; phytoplankton
; Postglacial
; reconstruction
; runoff
; sea ice
; sediment core
; solar activity
; Younger Dryas
; Arctic Ocean
; Laptev Sea
; Foraminifera
英文摘要: Multi-proxy biomarker measurements were applied on two sediment cores (PS51/154, PS51/159) to reconstruct sea ice cover (IP25), biological production (brassicasterol, dinosterol) and river run-off (campesterol, β-sitosterol) in the western Laptev Sea over the last ~17 ka with unprecedented temporal resolution. The absence of IP25 from 17.2 to 15.5 ka, in combination with minimum concentration of phytoplankton biomarkers, suggests that the western Laptev Sea shelf was mostly covered with permanent sea ice. Very minor river run-off and restricted biological production occurred during this cold interval. From ~16 ka until 7.5 ka, a long-term decrease of terrigenous (riverine) organic matter and a coeval increase of marine organic matter reflect the gradual establishment of fully marine conditions in the western Laptev Sea, caused by the onset of the post-glacial transgression. Intensified river run-off and reduced sea ice cover characterized the time interval between 15.2 and 12.9 ka, including the Bølling/Allerød warm period (14.7-12.9 ka). Prominent peaks of the DIP25 Index coinciding with maximum abundances of subpolar foraminifers, are interpreted as pulses of Atlantic water inflow on the western Laptev Sea shelf. After the warm period, a sudden return to severe sea ice conditions with strongest ice-coverage between 11.9 and 11 ka coincided with the Younger Dryas (12.9-11.6 ka). At the onset of the Younger Dryas, a distinct alteration of the ecosystem (reflected in a distinct drop in terrigenous and phytoplankton biomarkers) was detected. During the last 7 ka, the sea ice proxies reflect a cooling of the Laptev Sea spring/summer season. This cooling trend was superimposed by a short-term variability in sea ice coverage, probably representing Bond cycles (1500 ± 500 ka) that are related to solar activity changes. Hence, atmospheric circulation changes were apparently able to affect the sea ice conditions on the Laptev Sea shelf under modern sea level conditions. © 2016 Elsevier Ltd. Citation statistics:
资源类型: 期刊论文
标识符: http://119.78.100.158/handle/2HF3EXSE/59571
Appears in Collections: 过去全球变化的重建
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作者单位: Alfred Wegener Institute, Bremerhaven, Germany; Institute of Geology, University of Hamburg, Hamburg, Germany
Recommended Citation:
Hörner T.,Stein R.,Fahl K.,et al. Post-glacial variability of sea ice cover, river run-off and biological production in the western Laptev Sea (Arctic Ocean) - A high-resolution biomarker study[J]. Quaternary Science Reviews,2016-01-01,143