Fruergaard, Mikkel6; Andersen, Thorbjørn Joest6; Johannessen, Peter N3; Nielsen, Lars Henrik4; Pejrup, Morten7
1 Geography, Department of Geosciences and Natural Resource Management, Faculty of Science, Københavns Universitet2 SCIENCE Dean's Office, SCIENCE Faculty Office, Faculty of Science, Københavns Universitet3 Geological Survey of Denmark and Greenland4 Geological Survey of Denmark and Greenland - GEUS5 SCIENCE Faculty Management, SCIENCE Faculty Office, Faculty of Science, Københavns Universitet6 Geography, Department of Geosciences and Natural Resource Management, Faculty of Science, Københavns Universitet7 SCIENCE Faculty Management, SCIENCE Faculty Office, Faculty of Science, Københavns Universitet
Catastrophic storms and storm surges induce rapid and substantial changes along sandy barrier coasts, potentially causing severe environmental and economic damage. Coastal impacts of modern storms are associated with washover deposition, dune erosion, barrier breaching, and coastline and shoreface erosion. Little is however known about the impact of major storms and their post-storm coastal recovery on geologic and historic evolution of barrier systems. We apply high-resolution optically stimulated luminescence dating on a barrier system in the Wadden Sea (Denmark) and show that 5 to 8 meters of marine sand accumulated in an aggrading-prograding shoal and on a prograding shoreface during and within 3 to 4 decades (“healing phase”) after the most destructive storm documented for the Wadden Sea. Furthermore, we show that the impact of this storm caused large-scale shoreline erosion and barrier breaching. Our results demonstrate that violent, millennial-scale storms can trigger significant large-scale and long-term changes on barrier coasts, and that coastal changes assumed to take place over centuries or even millennia may occur in association with a single extreme storm event.