来自紧凑型漂流波浪浮标的表面斯托克斯漂移
Surface Stokes drift from compact drifting wave buoys
- eOdyn
- OceanDataLab
- Ifremer, Univ. Brest, CNRS, IRD, Laboratoire d’Océanographie Physique et Spatiale (LOPS)（法国海洋开发研究院，布列塔尼大学，法国国家科学研究中心，法国研发国际合作关系署，物理与空间海洋学实验室）
机构由 AI 辅助整理，请以论文原文为准。
AI总结：
本研究利用紧凑型漂流浮标测量数据，通过垂直加速度谱和方向矩计算表面斯托克斯漂移，并校准高频尾部，为模型评估提供约束。
AI中文摘要：
表面斯托克斯漂移强烈依赖于短波的能量和方向，而常规波浪观测无法完全解析这些短波。我们利用三次在东北大西洋和阿尔沃兰海部署期间由紧凑型漂流浮标收集的波浪测量数据，推导出表面斯托克斯漂移矢量。计算采用垂直加速度谱和第一方向傅里叶矩，这些描述了每个频率上的平均波向和方向集中度；计算考虑了浮标相对于水运动引起的多普勒频移，并在固有频率0.7赫兹以上添加了校准的高频尾部。在13,139条记录中，中位估计速度为0.081米/秒，中位风速为6.8米/秒。在0.04-1赫兹的测量频带上，考虑波向相对于单向假设使幅度中位数减少39%。参数化尾部（0.7赫兹以上）幅度与总估计幅度的中位数比值为0.37。与WAVEWATCH III和哥白尼海洋MFWAM的比较显示出强烈的协变性和相似的随风速变化的差异（相对于浮标估计值）。在来自两次大西洋部署的站点匹配样本上，WAVEWATCH III方向谱表明，这些在比较频带内的差异主要源于谱水平而非净方向缩减。观测结果为模型评估提供了约束；未解析短波的贡献仍对假设的谱尾及其方向扩展敏感。
英文摘要：
Surface Stokes drift depends strongly on the energy and directions of short waves, which are incompletely resolved by routine wave observations. We derive surface Stokes drift vectors from wave measurements collected by compact drifting buoys during three deployments in the North-East Atlantic and the Alboran Sea. The calculation uses vertical-acceleration spectra and first directional Fourier moments, which describe the mean wave direction and directional concentration at each frequency; it accounts for the Doppler shift caused by buoy motion relative to the water and adds a calibrated high-frequency tail above an intrinsic frequency of 0.7 Hz. Across 13,139 records, the median estimated speed is 0.081 m/s at a median wind speed of 6.8 m/s. Over the measured band of 0.04-1 Hz, accounting for wave directions reduces the magnitude by a median 39% relative to the unidirectional assumption. The median ratio of the parameterised tail magnitude above 0.7 Hz to the total estimated magnitude is 0.37. Comparisons with WAVEWATCH III and Copernicus Marine MFWAM show strong covariation and similar wind-dependent differences from the buoy-derived estimates. On the station-matched sample from the two Atlantic deployments, WAVEWATCH III directional spectra indicate that these differences within the compared band arise mainly from spectral levels rather than from net directional reduction. The observations provide constraints for model evaluation; the contribution of the unresolved short waves remains sensitive to the assumed spectral tail and its directional spreading.
