Process Contribution to the Time-Varying Residual Circulation in Tidally Dominated Estuarine Environments
Process Contribution to the Time-Varying Residual Circulation in Tidally Dominated Estuarine Environments
复制标题
DOI：
10.1007/s12237-013-9745-6
复制
发表时间：
2014-09-01
影响因子：
2.7
通讯作者：
Souza, Alejandro J.
中科院分区：
文献类型：
--
作者：
Brown, Jennifer M.;Bolanos, Rodolfo;Souza, Alejandro J.
在潮控环境中，余环流是除振荡潮流外相对较弱的净流。了解这种环流的三维结构对沿海管理非常重要，因为它影响悬浮颗粒的净（长期和事件尺度）运输和示踪剂量的平流。英国西北部的迪河口，用来了解哪些物理过程有一个重要的贡献，随时间变化的剩余环流。模式模拟用于提取随时间变化的贡献潮汐，河流（斜压性和流量），气象，外部和波过程，沿着他们的相互作用。在高潮条件下，强烈的半日相互作用内的剩余很难清楚地看到一个过程的影响，没有过滤。描述了一种将残差分离为孤立过程贡献和相互作用贡献的方法。将这种方法应用于两个高潮河口通道，一个潮汐占主导地位，一个斜压占主导地位，揭示了过程的相互作用可以作为重要的潮下剩余过程的贡献本身。剩余环流的时间变化突出了潮汐条件（小潮和春季周期）和近海风暴（风，波浪和浪涌影响）的事件尺度上不同的物理过程组件的影响。这使人们了解短期偏离典型的河口残留。这两个渠道被发现不同的反应相同的当地条件下，不同的短期变化过程中的优势，在事件的高，低能量。
In tide-dominated environments, residual circulation is the comparatively weak net flow in addition to the oscillatory tidal current. Understanding the 3D structure of this circulation is of importance for coastal management as it impacts the net (longer term and event-scale) transport of suspended particles and the advection of tracer quantities. The Dee Estuary, northwest Britain, is used to understand which physical processes have an important contribution to the time-varying residual circulation. Model simulations are used to extract the time-varying contributions of tidal, riverine (baroclinicity and discharge), meteorological, external and wave processes, along with their interactions. Under hypertidal conditions, strong semi-diurnal interaction within the residual makes it difficult to clearly see the effect of a process without filtering. An approach to separate the residual into the isolated process contribution and the contribution due to interaction is described. Applying this method to two hypertidal estuarine channels, one tide dominant and one baroclinic dominant, reveals that process interaction can be as important as the sub-tidal residual process contributions themselves. The time variation of the residual circulation highlights the impact of different physical process components at the event scale of tidal conditions (neap and spring cycles) and offshore storms (wind, wave and surge influence). This gives insight into short-term deviation from the typical estuarine residual. Both channels are found to react differently to the same local conditions, with different short-term change in process dominance during events of high and low energy.