A 1500‐year record of North Atlantic storm flooding from lacustrine sediments, Shetland Islands (UK)

• Published in: Journal of Quaternary Science
• Main Authors: Hess, Katharina, Engel, Max, Patel, Tasnim, Vakhrameeva, Polina, Koutsodendris, Andreas, Klemt, Eckehard, Hansteen, Thor H., Kempf, Philipp, Dawson, Sue, Schön, Isa, Heyvaert, Vanessa M. A.
• Format: Article in Journal/Newspaper
• Language: English
• Published: 2023
• Subjects: Little Ice Age; North Atlantic Oscillation (NAO); North Sea; sand overwash; storm frequency; /dk/atira/pure/subjectarea/asjc/1200/1201; name=Arts and Humanities (miscellaneous); /dk/atira/pure/subjectarea/asjc/1900/1911; name=Palaeontology; /dk/atira/pure/subjectarea/asjc/1900/1901; name=Earth and Planetary Sciences (miscellaneous); North Atlantic; North Atlantic oscillation; North East Atlantic
• Online Access: https://discovery.dundee.ac.uk/en/publications/35adbef3-d8bd-4263-a217-8219ecbf9a70; https://doi.org/10.1002/jqs.3568; https://discovery.dundee.ac.uk/ws/files/108100940/J_Quaternary_Science_-_2023_-_Hess.pdf; http://www.scopus.com/inward/record.url?scp=85171751057&partnerID=8YFLogxK

Severe storm flooding poses a major hazard to the coasts of north-western Europe. However, the long-term recurrence patterns of extreme coastal flooding and their governing factors are poorly understood. Therefore, high-resolution sedimentary records of past North Atlantic storm flooding are required. This multi-proxy study reconstructs storm-induced overwash processes from coastal lake sediments on the Shetland Islands using grain-size and geochemical data, and the re-analysis of historical data. The chronostratigraphy is based on Bayesian age–depth modelling using accelerator mass spectrometry 14C and 137Cs data. A high XRF-based Si/Ti ratio and the unimodal grain-size distribution link the sand layers to the beach and thus storm-induced overwash events. Periods with more frequent storm flooding occurred 980–1050, 1150–1300, 1450–1550, 1820–1900 and 1950–2000 ce, which is largely consistent with a positive North Atlantic Oscillation mode. The Little Ice Age (1400–1850 ce) shows a gap of major sand layers suggesting a southward shift of storm tracks and a seasonal variance with more storm floods in spring and autumn. Warmer phases shifted winter storm tracks towards the north-east Atlantic, indicating a possible trend for future storm-track changes and increased storm flooding in the northern North Sea region.