DOI: 10.1016/j.quascirev.2013.03.010
Scopus记录号: 2-s2.0-84876800046
论文题名: Abrupt holocene climate transitions in the northern north atlantic region recorded by synchronized lacustrine records in iceland
作者: Geirsdóttir T. ; Miller G.H. ; Larsen D.J. ; Ólafsdóttir S.
刊名: Quaternary Science Reviews
ISSN: 2773791
出版年: 2013
卷: 70 起始页码: 48
结束页码: 62
语种: 英语
英文关键词: 8.2 Event
; Abrupt climate transitions
; Holocene paleoclimate
; Holocene Thermal Maximum
; Iceland
; Lake sediment
; Little Ice Age
; Medieval warm period
; Neoglaciation
Scopus关键词: 8.2 events
; Climate transition
; Holocene thermal maximums
; Icelands
; Lake sediments
; Little Ice Age
; Medieval Warm Period
; Neoglaciation
; Paleoclimates
; Catchments
; Geochronology
; Glacial geology
; Sedimentology
; Sediments
; Silica
; Lakes
; accumulation
; atmospheric circulation
; deglaciation
; glacial lake
; Hypsithermal
; lacustrine deposit
; Little Ice Age
; Medieval Warm Period
; Neoglacial
; oceanic circulation
; paleoclimate
; paleomagnetism
; silica
; synchrony
; tephra
; time series
; upland region
; vegetation cover
; volcanism
; Atlantic Ocean
; Atlantic Ocean (North)
; Haukadalsvatn
; Hvitarvatn
; Iceland
英文摘要: Two high-sediment-accumulation-rate Icelandic lakes, the glacial lake Hvítárvatn and the non-glacial lake Haukadalsvatn, contain numerous tephra layers of known age, which together with high-resolution paleomagnetic secular variations allow synchronization with a well-dated marine core from the shelf north of Iceland. A composite standardized climate record from the two lakes provides a single time series that efficiently integrates multi-proxy data that reflect the evolution of summer temperatures through the Holocene. The first-order trends in biogenic silica (BSi), δ13C, and C:N rise relatively abruptly following deglaciation, reaching maximum values shortly after 8ka following a complex minimum between 8.7 and 8.0ka. The Holocene Thermal Maximum (HTM) in the lakes is marked by all proxies, with a sharp transition out of the 8ka cold event into peak summer warmth by 7.9ka, and continuing warm with some fluctuations until 5.5ka. Decreasing summer insolation after the HTM is reflected by incremental cooling, initially ~5.5ka, with subsequent cold perturbations recorded by all proxies 4.3 to 4.0ka and 3.1 to 2.8ka. The strongest disturbance occurred after 2ka with initial summer cooling occurring between 1.4 and 1.0ka, followed by a more severe drop in summer temperatures after 0.7ka culminating between 0.5 and 0.2ka. Following each late Holocene cold departure, BSi re-equilibrated at a lower value independent of the sediment accumulation rate. Some of the abrupt shifts may be related to Icelandic volcanism influencing catchment stability, but the lack of a full recovery to pre-existing values after the perturbation suggests increased periglacial activity, decreased vegetation cover, and glacier growth in the highlands of Iceland. The similarity in timing, direction and magnitude of our multi-proxy records from glacial and non-glacial lakes, and from the adjacent marine shelf, suggests that our composite record reflects large-scale shifts in ocean/atmosphere circulation throughout the northern North Atlantic. © 2013 Elsevier Ltd. Citation statistics:
资源类型: 期刊论文
标识符: http://119.78.100.158/handle/2HF3EXSE/60633
Appears in Collections: 过去全球变化的重建
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作者单位: Institute of Earth Sciences, University of Iceland, IS-101 Reykjavík, Iceland; INSTAAR, University of Colorado, Boulder, CO, United States; Department of Geological Sciences, University of Colorado, Boulder, CO, United States
Recommended Citation:
Geirsdóttir T.,Miller G.H.,Larsen D.J.,et al. Abrupt holocene climate transitions in the northern north atlantic region recorded by synchronized lacustrine records in iceland[J]. Quaternary Science Reviews,2013-01-01,70