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, SCHON, Isa, Heyvaert, Vanessa M. A.
• Other Authors: Hess, Katharina/0000-0002-1621-5466; Koutsodendris, Andreas/0000-0003-4236-7508
• Format: Article in Journal/Newspaper
• Language: English
• Published: WILEY 2023
• Subjects: Little Ice Age; North Atlantic Oscillation (NAO); North Seasand overwash; storm frequency; Renard; North Atlantic; North Atlantic oscillation; North East Atlantic
• Online Access: http://hdl.handle.net/1942/41848; https://doi.org/10.1002/jqs.3568

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. This study was funded by Belspo (BR/175/PI/ GEN‐EX). Geotek core logging at Renard Center of Marine Geology, Ghent University, and the support by Evelien Boes are greatly appreciated. Permission to access Loch Flugarth was kindly granted by local land owners. Thanks are also expressed to Oliver A. Kern for technical support. We thank Alastair G. Dawson for useful comments, which helped us to greatly improve this article. Witold Szczuciński and Graeme Swindles are acknowledged for their very helpful reviews. Open Access funding was enabled and organized by Projekt DEAL.