Evaluating XBeach performance for extreme offshore-directed sediment transport events on a dissipative beach
Evaluating XBeach performance for extreme offshore-directed sediment transport events on a dissipative beach
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DOI：
10.1080/21664250.2021.1976452
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发表时间：
2021-09
影响因子：
2.4
通讯作者：
Takayuki Suzuki;D. Cox
中科院分区：
文献类型：
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作者：
Takayuki Suzuki;D. Cox
摘要利用在日本一个耗散海滩的现场观测，研究了基于过程的近岸模式X海滩预测极端离岸定向泥沙输运的性能。从1987年至2003年在日本Hasaki的6，209次跨海岸剖面变化观测记录中确定了三次极端侵蚀事件。该分析考虑了短波的波非线性的敏感性，可以使用参数fua对观测到的床面剖面变化进行调整。比较结果显示，对于极端的离岸定向输沙事件，fua = 0.0是预测这些极端海滩剖面变化的最佳拟合。在近岸区，侵蚀被低估，BSS表现出较低的值。峰值沉积物沉积发生在酒吧离岸区与沉积物从近岸区，并估计模型合理。除了这三个极端事件外，还识别出了14个其他大事件，通过充分调整fua参数，可以估计海滩剖面变化的趋势。在分析fua与波形及形态学相关参数的相关性后，fua值可与所观察到的体积变化相关。这表明，如果对预期的总体积变化有一个粗略的估计，这可能有助于设定fua值。
ABSTRACT The performance of the process-based nearshore model XBeach for predicting extreme offshore-directed sediment transport was investigated using field observations at a dissipative beach in Japan. Three extreme erosion events were identified from a record of 6,209 observations of the cross-shore profile change at Hasaki, Japan, from 1987 to 2003. The analysis considered the sensitivity of the wave nonlinearity of short waves that could be tuned using the parameter, fua , to the observed bed profile change. The comparisons revealed that for extreme offshore-directed sediment transport events, fua = 0.0 is the best fit for predicting these extreme beach profile changes. In the nearshore zone, erosion was underestimated, and the BSS exhibited low values. Peak sediment deposition occurred in the bar-offshore zone with sediments transported from the nearshore zone and was estimated by the model reasonably well. In addition to the three extreme events, 14 other large events were identified, and the trends of beach profile change could be estimated with sufficient tuning of the fua parameter. After analyzing the correlation between fua and wave and morphology-related parameters, the fua value could be correlated to the observed volume change. This suggested that if there were a rough estimate of the expected total volume change, this may help in setting fua value.