论文标题
一个由非线性相互作用主导的内波频谱的简单模型
A simple model for an internal wave spectrum dominated by non-linear interactions
论文作者
论文摘要
内波带的频率下的海洋运动通常与稳定的垂直分层密度支持的自由传播波有关。先前对比斯开湾的为期一年的观察结果的分析表明，半职潮汐和近乎惯性的较高谐波的罚款填补了频谱。在这里，一个简单的模型与正向能量级联反应强迫非分散运动。该模型符合较高谐波的频谱形状在统计意义之内，表明这种相互作用意味着在强迫和湍流混合之间的平衡中最大的波浪陡度。单个拟合参数与正压潮流流速有关，从而在不直接产生非线性较高谐波的情况下将非线性极限设定为斜线电流尺度。
Ocean motions at frequencies of the internal wave band are generally associated with freely propagating waves that are supported by stable vertical stratification in density. Previous analyses of yearlong current observations from the Bay of Biscay showed that a finestructure of semidiurnal tidal and near-inertial higher harmonics fills the spectrum. Here, a simple model is presented of forced nondispersive motions with forward energy cascade. The model fits the spectral shape of higher harmonics well within statistical significance and shows that such interactions imply maximum wave steepness in a balance between forcing and turbulent mixing. The single fitting parameter is related to the barotropic tidal flow speed, which thereby sets a nonlinear limit to baroclinic current scales without generating non-linear higher harmonics directly.
