Geohazards Research Unit, Institute of Geology, Adam Mickiewicz University, Bogumiła Krygowskiego 12, 61-680, Poznań, Poland.
Department of Geomorphology and Quaternary Geology, University of Gdańsk, Bażyńskiego 4, 80-952, Gdańsk, Poland.
Sci Rep. 2022 Jun 11;12(1):9710. doi: 10.1038/s41598-022-13860-4.
Climate change and related sea-level rise pose significant threats to lowland coasts. However, the role of key controlling factors responsible for the frequency and landward extent of extreme storm surges is not yet fully understood. Here, we present a high-resolution sedimentary record of extreme storm surge flooding from the non-tidal southern Baltic Sea, spanning two periods: 3.6-2.9 ka BP and 0.7 ka BP until present. Sediments from coastal wetland, including sandy event layers, were analyzed by sedimentological (grain size, loss-on-ignition, micromorphology), geochronological (C), geochemical (XRF), mineralogical (heavy minerals) and micropaleontological (diatoms) methods. The results show that both periods were characterized by high-frequency of storm surge flooding, in order of 1.3-4.2 events per century. These periods correlate with phases of enhanced storminess in northwest Europe and took place during both rising and fluctuating sea levels. The study shows that the frequency and landward extent of coastal inundation, largely depended on the development of natural barriers (e.g. beach ridges and aeolian foredunes). Thus, in the context of the future coastal storm-surge hazard, the protection of existing coastal barriers and their morphology is essential.
气候变化及相关海平面上升对低地海岸构成了重大威胁。然而，导致极端风暴潮频率和向陆延伸程度的关键控制因素的作用尚不完全清楚。在这里，我们呈现了一个来自无潮波罗的海南部的极端风暴潮洪水的高分辨率沉积记录，跨越两个时期：3600-2900 年前和 700 年前至今。我们通过沉积学（粒度、烧失量、微形态学）、地球化学（碳）、地球化学（XRF）、矿物学（重矿物）和微体古生物学（硅藻）方法对来自滨海湿地的沉积物（包括沙质事件层）进行了分析。结果表明，这两个时期都以每世纪 1.3-4.2 次事件的高频率特征为特征。这些时期与西北欧风暴活动增强的阶段相关，并发生在海平面上升和波动期间。该研究表明，海岸淹没的频率和向陆延伸程度在很大程度上取决于自然屏障（如海滩脊和风沙前沙丘）的发展。因此，在未来沿海风暴潮灾害的背景下，保护现有海岸屏障及其形态至关重要。
