The complexity of millennial-scale variability in southwestern Europe during MIS 11

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• 作者：Dulce Oliveira^a ; ^b ; ^c ; ^d ; ^{dulce.oliveira@ipma.pt} ; Sté ; phanie Desprat^a ; ^b ; Teresa Rodrigues^c ; ^d ; Filipa Naughton^c ; ^d ; David Hodell^e ; Ricardo Trigo^f ; Marta Rufino^c ; ^d ; Cristina Lopes^c ; ^d ; Fá ; tima Abrantes^c ; ^d ; Maria Fernanda Sá ; nchez Goñ ; i^a ; ^b
• 关键词：Marine Isotope Stage (MIS) 11 ; Iberian margin ; Mediterranean vegetation ; Millennial-scale climate variability ; Cooling events ; Land&ndash ; sea comparison ; Pollen analysis
• 刊名：Quaternary Research
• 出版年：2016
• 出版时间：November 2016
• 年：2016
• 卷：86
• 期：3
• 页码：373-387
• 全文大小：3188 K
• 卷排序：86

文摘

Climatic variability of Marine Isotope Stage (MIS) 11 is examined using a new high-resolution direct land–sea comparison from the SW Iberian margin Site U1385. This study, based on pollen and biomarker analyses, documents regional vegetation, terrestrial climate and sea surface temperature (SST) variability. Suborbital climate variability is revealed by a series of forest decline events suggesting repeated cooling and drying episodes in SW Iberia throughout MIS 11. Only the most severe events on land are coeval with SST decreases, under larger ice volume conditions. Our study shows that the diverse expression (magnitude, character and duration) of the millennial-scale cooling events in SW Europe relies on atmospheric and oceanic processes whose predominant role likely depends on baseline climate states. Repeated atmospheric shifts recalling the positive North Atlantic Oscillation mode, inducing dryness in SW Iberia without systematical SST changes, would prevail during low ice volume conditions. In contrast, disruption of the Atlantic meridional overturning circulation (AMOC), related to iceberg discharges, colder SST and increased hydrological regime, would be responsible for the coldest and driest episodes of prolonged duration in SW Europe.