Observations of runup and energy flux on a low‐slope beach with high‐energy, long‐period ocean swell
Observations of runup and energy flux on a low‐slope beach with high‐energy, long‐period ocean swell
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具有高能量、长周期海洋涌浪的低坡海滩上的上升和能量通量观测
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发表时间：
2015
期刊：
影响因子：
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通讯作者：
R. Guza
中科院分区：
文献类型：
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作者：
Julia W. Fiedler;K. Brodie;J. McNinch;R. Guza
在俄勒冈州低坡度(1/80)的玛瑙海滩上，利用海流计、压力传感器和扫描激光雷达的横断面，观测到了表面重力波从11m深度到爬升的转变。近海波高H0从平静(0.5米)到活跃(>；7米)不等。用压力传感器和扫描激光雷达测量的跳跃随(H0L0)1/2线性增加，L0是光谱峰值的深水波长。尽管(H0L0)1/2进一步增加，但没有观察到RUP饱和，其中RUP振荡处于平稳状态。在次重力波能量平衡中考虑了次重力波浅化和与短波的非线性能量交换。这一平衡在高重力频率(0.025-0.04赫兹)时关闭，但在较低频率(0.003-0.025赫兹)时不关闭，这可能是由于波浪破碎和/或底部摩擦的未建模的重力能量损失。耗散过程限制，但不是完全抑制，增加的助跑，以响应增加的入射波强迫。
The transformation of surface gravity waves from 11 m depth to runup was observed on the low‐sloped (1/80) Agate Beach, Oregon, with a cross‐shore transect of current meters, pressure sensors, and a scanning lidar. Offshore wave heights H0 ranged from calm (0.5 m) to energetic (>7 m). Runup, measured with pressure sensors and a scanning lidar, increases linearly with (H0L0)1/2, with L0 the deep‐water wavelength of the spectral peak. Runup saturation, in which runup oscillations plateau despite further increases in (H0L0)1/2, is not observed. Infragravity wave shoaling and nonlinear energy exchanges with short waves are included in an infragravity wave energy balance. This balance closes for high‐infragravity frequencies (0.025–0.04 Hz) but not lower frequencies (0.003–0.025 Hz), possibly owing to unmodeled infragravity energy losses of wave breaking and/or bottom friction. Dissipative processes limit, but do not entirely damp, increases in runup excursions in response to increased incident wave forcing.