Collaborative Research: Impact of Langmuir Circulation on Gas Transfer and Photosynthesis in the Southern Ocean: A Large Eddy Simulation Study

上层海洋混合层(UOML)中的朗缪尔环流(LC)是一种最常见的特征，它表现为与风向大致平行的线性条纹或海面条纹。这是由于螺旋(卵圆形)水胞顺时针和逆时针旋转，在表面形成了汇聚(下流)和发散(上行)交替的带。风速决定了这些环流圈的深度和间距。作为UOML表面更新的驱动力，LC可能负责以下过程：发散区捕获浮游植物并将其向上输送至表面，以及汇聚区收集表面活性剂和可转移气体并将其下沉到水柱中。来自南佛罗里达大学和史密森研究中心的研究人员希望在南极海洋学感兴趣的两个主题上扩展对LC影响的数值模拟研究，首先，a)南极夏季光场下浮游植物初级生产力的光抑制(包括表面UV穿透的影响)，以及可能的，b)海-气气体交换的参数化。最近的两个现场数据集，包括罗斯海波利纳和南大洋天然气实验(SO-GASEX)的生产率研究，将成为比较现场数据与使用大涡模拟(LES)对LC效应进行精细数值计算的基础。“该奖项是根据2009年美国复苏和再投资法案(公共法律111-5)资助的。”

Langmuir circulation (LC) in the upper ocean mixed layer (UOML) is a feature most familiarly observed as linear stripes or sea surface streaks approximately parallel to the wind direction. These result from helical (ovoid) water cells rotating clockwise and anticlockwise, forming alternating bands of convergence (downwelling) and divergence (upwelling) at the surface. Windspeed determines the depth and the spacings of these circulation cells. As a driver of surface renewal in the UOML, LC may then be responsible for processes such as divergence zone capture and transport of phytoplankton upwards to the surface and the convergence zone collection and sinking of surfactants and transferable gases into the water column. Investigators from the University of South Florida and the Smithsonian Research Center wish to extend numerical modeling studies of the effects of LC on two topics of interest to Antarctic oceanography, firstly, a) photoinhibition of the primary productivity of phytoplankton under Antarctic summer light fields (including effects of surface UV penetration) and possibly, b) parameterizations of sea-air gas exchange. Two recent field data sets including productivity studies in the Ross Sea polyna and the Southern Ocean Gas Experiment (SO-GasEx) will form the basis for comparisons of field data with fine scale numerical computations of LC effects using large-eddy simulations (LES)."This award is funded under the American Recovery and Reinvestment Act of 2009 (Public Law 111-5)."