气候变化领域集成服务门户(CCPortal): A revised chronology for the growth and demise of Loch Lomond Readvance (‘Younger Dryas’) ice lobes in the Lochaber area; Scotland

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DOI	10.1016/j.quascirev.2020.106548
	A revised chronology for the growth and demise of Loch Lomond Readvance (‘Younger Dryas’) ice lobes in the Lochaber area; Scotland
	Palmer A.P.; Matthews I.P.; Lowe J.J.; MacLeod A.; Grant R.
发表日期	2020
ISSN	0277-3791
卷号	248
英文摘要	We present a revised varve chronology for the duration of ice-dammed lakes that formed in the Lochaber district, Scotland, during the Loch Lomond (‘Younger Dryas’) Stadial. We analysed new varved sequences and combined them with existing varve records to develop the Lochaber Master Varve Chronology 2019 (LMVC19), published here for the first time. It spans an interval of 518 ± 18 vyrs and is considered more secure than its predecessors because: (i) it is anchored by a more robust record of the Vedde Ash, which is dated to 12,043 ± 43 cal yr BP; and (ii) it provides revised estimates of the timings of key regional palaeoclimatic shifts that are fully compatible with those inferred from independently-dated, non-varved records obtained from neighbouring sites. The new results indicate that the Lochaber ice-dammed lakes existed between ∼12,135 and 11,618 ± 61 cal yr BP, but the pattern of glacier advance that led to lake formation was more complex than previously assumed, with some ice fronts reaching their maximal positions 300 years before others. Initiation of ice retreat at ∼11,800 cal yr BP appears to have coincided with a rise of ∼2 °C in mean July temperatures inferred from chironomid data obtained from the Abernethy Forest site in the eastern Highlands. This local climatic shift is thought to have been a delayed response (by up to 335 years) to a mid-Stadial northward migration of the North Atlantic Polar Front, the delay probably due to the influence of the SW Highland icefield. Subsequent retreat that led to the formation of ice stagnation features throughout large parts of the area was initiated by a further rise in summer air temperature of ∼3 °C at the start of the Early Holocene. Final drainage of the lake system occurred ∼190 years after the initiation of ice retreat, while it took a further 200 years for the ice to vacate the Rannoch plateau, a nearby upland glacial source. © 2020 The Author(s)
英文关键词	Bayesian age-modelling; Glacier dynamics; Palaeoclimatic inferences; Tephrochronology; Varve chronology
语种	英语
scopus关键词	Lakes; Air temperature; Climatic shifts; Delayed response; Early Holocene; Fully compatible; Ice-dammed lake; North Atlantic; Varve chronologies; Ice; air temperature; dendrochronology; glacier advance; growth; Holocene; ice retreat; ice-dammed lake; paleoclimate; Younger Dryas; Abernethy Forest; Atlantic Ocean; Atlantic Ocean (North); Highland; Loch Lomond; Scotland; Scotland; United Kingdom; Chironomidae
来源期刊	Quaternary Science Reviews
文献类型	期刊论文
条目标识符	http://gcip.llas.ac.cn/handle/2XKMVOVA/151286
作者单位	Centre for Quaternary Research, Department of Geography, Royal Holloway, University of London, Surrey TW20 0EX, Egham, United Kingdom; Department of Geography, University of Reading, Whiteknights Campus, Berkshire RG6 6ABReading, United Kingdom
推荐引用方式 GB/T 7714	Palmer A.P.,Matthews I.P.,Lowe J.J.,等. A revised chronology for the growth and demise of Loch Lomond Readvance (‘Younger Dryas’) ice lobes in the Lochaber area; Scotland[J],2020,248.
APA	Palmer A.P.,Matthews I.P.,Lowe J.J.,MacLeod A.,&Grant R..(2020).A revised chronology for the growth and demise of Loch Lomond Readvance (‘Younger Dryas’) ice lobes in the Lochaber area; Scotland.Quaternary Science Reviews,248.
MLA	Palmer A.P.,et al."A revised chronology for the growth and demise of Loch Lomond Readvance (‘Younger Dryas’) ice lobes in the Lochaber area; Scotland".Quaternary Science Reviews 248(2020).