Swell wave progression in the English Channel: implications for coastal monitoring
Swell wave progression in the English Channel: implications for coastal monitoring
复制标题
英吉利海峡的涌浪进展：对沿海监测的影响
作者：
Thomas Dhoop;Charlie Thompson
强烈的海浪，特别是当它们与高水位同时出现时，会对海岸造成重大危害。为了更好地了解和预测这些风险，分析产生这些事件的海平面和海浪以及由此产生的沿海影响至关重要。在英吉利海峡接连发生了两次剧烈的涌浪事件，而模拟洪水预报都没有预测到这两次事件。第一次事件发生在2021年1月30日，在英国西南海岸产生了中等或略低于0.25年回归期的显著浪高，但与显著的涌浪相结合，导致西湾东海滩和切西尔海滩的海水漫过。第二次事件发生在2021年2月1日，在英国南部海岸线的许多地方产生了最高的波能周期，在高水位时，海浪冲过了普尔湾和克赖斯特彻奇湾的海滨长廊，并在海灵岛造成了海水漫过。详细描述了这两个事件，并通过使用联结函数的联合回归期分析绘制了它们的空间足迹。典型的水位和显著波高联合回归期分析低估了潜在影响，而水位和波能(P)联合考虑较好地描述了1月31日事件，水位和能期（Te）联合考虑最能描述2月1日事件。因此，建议采用Te和P进行海岸监测，未来的研究将进一步探讨使用这两个参数进行涌浪监测。
Energetic swell waves, particularly when they coincide with high water levels, can present significant coastal hazards. To better understand and predict these risks, analysis of the sea levels and waves that generate these events and the resulting coastal impacts is essential. Two energetic swell events, neither of which were predicted by modelled flood forecasts, occurred in quick succession in the English Channel. The first event, on 30 January 2021, produced moderate significant wave heights at or just below the 0.25 year return period along the southwest English coast, but combined with significant swell caused overtopping at East Beach in West Bay and at Chesil Beach. The second event, on 1 February 2021, generated the highest wave energy periods measured at many locations along the southern English coastline and, at high water, caused waves to run up over the promenades at Poole Bay and Christchurch Bay and caused overtopping at Hayling Island. Both events are described in detail, and their spatial footprints are mapped through a joint return period analysis using a copula function. It is found that typical joint return period analysis of water level and significant wave height underestimates potential impacts, while a joint consideration of water level and wave power (P) describes the 31 January event better and a joint consideration of water level and energy period (Te) best describes the 1 February event. Therefore, it is recommended that Te and P are adopted for coastal monitoring purposes, and that future studies further explore the use of both parameters for swell monitoring.