气候变化领域集成服务门户(CCPortal): Multiproxy evidence of the Neoglacial expansion of Atlantic Water to eastern Svalbard

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DOI	10.5194/cp-16-487-2020
	Multiproxy evidence of the Neoglacial expansion of Atlantic Water to eastern Svalbard
	Pawłowska J.; Łącka M.; Kucharska M.; Pawlowski J.; Zajączkowski M.
发表日期	2020
ISSN	18149324
起始页码	487
结束页码	501
卷号	16 期号:2
英文摘要	The main goal of this study is to reconstruct the paleoceanographic development of Storfjorden during the Neoglacial (∼ 4 cal ka BP). Storfjorden is one of the most important brine factories in the European Arctic and is responsible for deepwater production. Moreover, it is a climate-sensitive area influenced by two contrasting water masses: warm and saline Atlantic Water (AW) and cold and fresh Arctic Water (ArW). Herein, a multiproxy approach was applied to provide evidence for existing interactions between the inflow of AW and sea ice coverage, which are the major drivers of environmental changes in Storfjorden. The sedimentary and microfossil records indicate that a major reorganization of oceanographic conditions in Storfjorden occurred at ∼ 2.7 cal ka BP. The cold conditions and the less pronounced presence of AW in Storfjorden during the early phase of the Neoglacial were the prerequisite conditions for the formation of extensive sea ice cover. The period after 2.7 cal ka BP was characterized by alternating short-term cooling and warming intervals. Warming was associated with pulsed inflows of AW and sea ice melting that stimulated phytoplankton blooms and organic matter supply to the bottom. The cold phases were characterized by heavy and densely packed sea ice, resulting in decreased productivity. The ancient environmental DNA (aDNA) records of foraminifera and diatoms support the occurrence of the major pulses of AW (∼ 2.3 and ∼ 1.7 cal ka BP) and the variations in sea ice cover. The episodes of enhanced AW inflow were marked by an increase in the percentage of DNA sequences of monothalamous foraminifera associated with the presence of fresh phytodetritus. Cold and less productive intervals were marked by an increased proportion of monothalamous taxa known only from environmental sequencing. The diatom aDNA record indicates that primary production was continuous during the Neoglacial, regardless of the sea ice conditions. However, the colder periods were characterized by the presence of diatom taxa associated with sea ice, whereas the present-day diatom assemblage is dominated by open-water taxa. © Author(s) 2020.
语种	英语
scopus关键词	brine; DNA; foraminifera; genetic analysis; melting; microfossil; Neoglacial; paleoceanography; phytoplankton; primary production; sea ice; Arctic; Atlantic Ocean; Spitsbergen; Storfjorden; Svalbard; Svalbard and Jan Mayen; Bacillariophyta; Foraminifera
来源期刊	Climate of the Past
文献类型	期刊论文
条目标识符	http://gcip.llas.ac.cn/handle/2XKMVOVA/146735
作者单位	Institute of Oceanology, Polish Academy of Sciences, Sopot, 81-712, Poland; Department of Genetics and Evolution, University of Geneva, Geneva, CH 1211, Switzerland
推荐引用方式 GB/T 7714	Pawłowska J.,Łącka M.,Kucharska M.,et al. Multiproxy evidence of the Neoglacial expansion of Atlantic Water to eastern Svalbard[J],2020,16(2).
APA	Pawłowska J.,Łącka M.,Kucharska M.,Pawlowski J.,&Zajączkowski M..(2020).Multiproxy evidence of the Neoglacial expansion of Atlantic Water to eastern Svalbard.Climate of the Past,16(2).
MLA	Pawłowska J.,et al."Multiproxy evidence of the Neoglacial expansion of Atlantic Water to eastern Svalbard".Climate of the Past 16.2(2020).