Calculating lateral plume spreading with surface Lagrangian drifters
Calculating lateral plume spreading with surface Lagrangian drifters
复制标题
使用表面拉格朗日漂移器计算横向羽流扩散
DOI：
10.1002/lom3.10356
复制
发表时间：
2020
期刊：
影响因子：
--
通讯作者：
Cole, Kelly
中科院分区：
文献类型：
--
作者：
Kakoulaki, Georgia;MacDonald, Daniel G.;Cole, Kelly
这项工作提供了一个罕见的量化从拉格朗日测量在浮力河羽通过比较四种方法横向扩散。漂移运动，包括沿流剪切和旋转，可能被错误地解释为横向扩展。这项工作旨在通过识别漂移轨迹中的附加运动来改善对横向扩散的估计。首先对所应用的技术进行评估和比较，使用一组理想的漂流体进行特定类型的运动，然后将其应用于在各种不同环境条件下释放在梅里马克河羽流（马萨诸塞州）的27个表面拉格朗日漂流体的原位数据。所测试的技术包括两种方法，使用漂浮物位置的标准偏差相对于各种平均漂浮物方向的解释和两种方法，使用旋转椭圆坐标参考系。将每种类型的运动（即扩散、旋转和剪切）分别对理想轨迹进行分析建模，然后进行不同的组合，以确定最佳解决和隔离横向扩散的方法。理想化实验表明，这三种方法在不同组合下对剪切和旋转运动都很敏感。解决横向扩散最稳健的方法是“时间步长”方法，该方法采用参考框架，遵循每个时间步长的平均流量，计算为两个时间步长之间漂移者的平均方向。该方法还成功地识别了观测中的横向扩展，这在经典的凸起状羽流部署中是最大的。这项工作适用于其他河流羽流系统以及其他传播的海洋现象。
This work provides a rare quantification of lateral spreading from Lagrangian measurements in a buoyant river plume by comparing four methods. Drifter motions, including along‐stream shear and rotation, can be incorrectly interpreted as lateral spreading. This work aims to improve estimates of lateral spreading by identifying additional motions in drifter trajectories. The techniques applied are first evaluated and compared using an idealized group of drifters undergoing specific types of motion, and then applied to in situ data from 27 surface Lagrangian drifters released in the Merrimack River plume (Massachusetts) under a variety of different environmental conditions. The techniques tested include two methods using the standard deviation of drifter position with respect to various interpretations of mean drifter direction and two methods using a rotating elliptical coordinate reference frame. The idealized trajectories are modeled analytically with each type of motion (i.e., spreading, rotation, and shear) separately, then in different combinations, to identify the method that best resolves and isolates lateral spreading. The idealized experiments demonstrate that three of the methods are sensitive to shear and rotational motion in various combinations. The most robust method resolving lateral spreading is the “time‐step” method, which applies a reference frame that follows the mean flow at each time step, calculated as the average direction of the drifters between two time steps. This method also successfully identifies lateral spreading in observations, which is maximized in classic bulge‐shaped plume deployments. This work is applicable to other river plume systems as well as other propagating oceanographic phenomena.
登录
查看更多内容
浮力表面羽流中的湍流和夹带
影响因子：
--
作者：
D. Luketina;J. Imberger
通讯作者：
J. Imberger
DOI：
10.1016/s9999-9994(08)20541-6
发表时间：
2010
期刊：
Journal of End-to-end-testing
影响因子：
--
作者：
R. Hetland
通讯作者：
R. Hetland
通过分层剪切流中的横向扩散增强湍流：概念模型的开发和评估
影响因子：
--
作者：
D. MacDonald;Fei Chen
通讯作者：
Fei Chen
非潮汐状态下风向和混合对浮力羽流扩散的影响
影响因子：
2.4
作者：
J. Xing;A. M. Davies
通讯作者：
A. M. Davies
风在河流羽流近场和中场中的作用
影响因子：
5.2
作者：
G. Kakoulaki;D. MacDonald;A. Horner‐Devine
通讯作者：
A. Horner‐Devine