Abstract At the nearshore area of Norderney, the ebb-tidal delta (ETD) sandbanks exert a huge impact on the local wave climate, which is of particular interest for coastal protection. Besides an eastward migration of the sandbanks with a mean velocity from 435 to 491 m / y , depending on the plates position, the ETD sandbanks had a high variability in shape and size. Therefore, the influence of those morphodynamic changes on the sea state damping effect was quantified by dynamic bathymetries using validated SWAN simulations. The impacts of the bathymetries from the years 1995, 2005, 2006, 2008, and 2015 with highest morphological variability were considered for five different boundary conditions, representing storm surge events of the Norderney nearshore wave climate. A mean variation of 14 ± 2 % of the relative sea state damping effect was found for the different bathymetries of the ETD sandbanks at the various boundary conditions. Swell waves showed a range of 16 ± 2 % for the damping effect, which increased with increasing incoming wave height. Buoy data off the Norderney coast from 1992 to 2017 were investigated and a mean buoy-measured damping effect of 0.37 was determined over the entire period. General results of SWAN modeling were also found in the in-situ measurements.

中文翻译：

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东弗里斯兰北海近岸地区板块形态动力学变异性和海况阻尼的量化

摘要 在诺德奈岛近岸地区，退潮三角洲（ETD）沙洲对当地的波浪气候产生了巨大的影响，这对海岸保护尤为重要。除了平均速度为 435 至 491 m / y 的沙洲向东迁移外，ETD 沙洲的形状和尺寸变化很大，这取决于板块位置。因此，这些形态动力学变化对海况阻尼效应的影响通过动态测深使用经过验证的 SWAN 模拟进行量化。考虑了 1995 年、2005 年、2006 年、2008 年和 2015 年具有最高形态变异性的水深测量对五种不同边界条件的影响，代表了诺德奈岛近岸波浪气候的风暴潮事件。对于不同边界条件下 ETD 沙洲的不同水深，发现相对海况阻尼效应的平均变化为 14 ± 2 %。涌浪的阻尼效应范围为 16 ± 2 %，随着入射波高度的增加而增加。调查了 1992 年至 2017 年诺德奈海岸附近的浮标数据，并确定了整个时期浮标测量的平均阻尼效应为 0.37。在原位测量中也发现了 SWAN 建模的一般结果。在整个期间确定了 37 个。在原位测量中也发现了 SWAN 建模的一般结果。在整个期间确定了 37 个。在原位测量中也发现了 SWAN 建模的一般结果。