Climate forcing of regionally-coherent extreme storm impact and recovery on embayed beaches
Climate forcing of regionally-coherent extreme storm impact and recovery on embayed beaches
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DOI：
10.1016/j.margeo.2018.04.004
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发表时间：
2018-07
期刊：
影响因子：
2.9
通讯作者：
Olivier Burvingt;G. Masselink;T. Scott;Mark S. Davidson;P. Russell
中科院分区：
文献类型：
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作者：
Olivier Burvingt;G. Masselink;T. Scott;Mark S. Davidson;P. Russell
沉积海岸线的有效管理需要很好地了解海滩量的季节性和年际周期，以及极端事件的潜在影响。本文使用了10年的时间序列（2007-2017年）的潮上和潮间海滩量从暴露和跨岸运输为主的网站，以检查在多大程度上海滩行为是连贯的一个相对较大的区域（100公里的海岸延伸），并可预测地耦合到入射波强迫。在研究期间，10个海滩，暴露于类似的波浪/潮汐条件，但具有不同的沉积物特性，海滩长度和海湾化程度，显示出一致和同步的变化，在沉积物量，虽然在不同的幅度。2013/14年冬季的极端风暴序列，代表了欧洲大西洋沿岸大部分地区至少十年来最具侵蚀性的事件，被纳入数据集，今年冬天三年后，10个海滩中的一些海滩仍在恢复中。风暴后的海滩恢复被证明主要是由风暴后的冬季波浪条件控制，而夏季条件始终有助于适度的海滩恢复。使用平衡型海岸线模型（ShoreFor; Davidson等人，2013年），表明海滩的变化与近海波浪气候的变化密切相关，并对前期条件敏感。ShoreFor模型可以成功地应用于以跨海岸沉积物运输为主的裸露沿海地区，也可以作为一个相对简单的区域工具，用于今后管理沿海响应一致性的海滩。此外，发现海滩体积变化与新的气候指数WEPA（西欧压力异常; Castelle等人，2017年b），为气候变化替代指标在预测海岸线演变方面的作用和使用提供了新的视角。
The effective management of sedimentary coastlines demands a good understanding of the seasonal and inter-annual cycles in beach volumes, as well as the potential impact of extreme events. This paper uses a 10-year time series (2007–2017) of supra- and intertidal beach volume from exposed and cross-shore transport-dominated sites to examine the extent to which beach behaviour is coherent over a relatively large region (100-km stretch of coast) and predictably coupled to incident wave forcing. Over the study period, 10 beaches, exposed to similar wave/tide conditions, but having different sediment characteristics, beach lengths and degrees of embaymentisation, showed coherent and synchronous variations in sediment volumes, albeit at different magnitudes. The sequence of extreme storms of the 2013/14 winter, which represents the most erosive event over at least a decade along most of the Atlantic coast of Europe, is included in the data set, and three years after this winter, beach recovery is still on-going for some of the 10 beaches. Post-storm beach recovery was shown to be mainly controlled by post-storm winter wave conditions, while summer conditions consistently contributed to modest beach recovery. Skilful hindcasts of regional changes in beach volume were obtained using an equilibrium-type shoreline model (ShoreFor; Davidson et al., 2013), demonstrating that beach changes are coherently linked to changes in the offshore wave climate and are sensitive to the antecedent conditions. The ShoreFor model can successfully be applied to exposed coastal areas dominated by cross-shore sediment transport, and can also be used as a relatively simple and regional tool for the future management of beaches where coherence in coastal response is observed. Furthermore, a good correlation was found between the beach volume changes and the new climate index WEPA (West Europe Pressure Anomaly; Castelle et al., 2017b), which offers new perspectives for the role and the use of climatic variations proxies to forecast coastline evolution.