Collaborative Research: Dye Tracer and Modeling Investigations of Cross-Shelf Circulation during Coastal Upwelling

DALE0136900现场和模拟研究将被用来确定上涌水的来源，即仅来自底部边界层(BBL)或来自较厚的低层流体区域，以及置换的地表水流向哪里，例如，在表层的近海，或通过俯冲进入中间层。对于俄勒冈州陆架上方的上升区，提出了五项使用荧光素和罗丹明-WT的染料研究。释放将发生在三个不同的位置--上升流急流的下方和近岸，在急流下方的边界层中，预计会有陆上运动，以及急流的近岸，就在混合层下面，但仍在埃克曼层，预计会有离岸运动和可能的俯冲。染料将被追踪72小时。至少在第一个实地考察年期间，背景环境将由GLOBEC巡航确定。将在第一年追踪R/V Elakha的三个版本。第二年将包括从R/V Wecoma发布的两个更大的版本。将运行为该地区配置的普林斯顿海洋模型的一个版本进行比较。粒子追踪技术将被用来模拟初始的小规模扩散。我们将尝试理想化的场景和逼真的建模。将使用2-D远洋模型，结合浮标GPS漂移器，在释放后跟踪地下染料斑块。这项研究的结果将是对上升流过程中跨陆架输送路径的一组拉格朗日观测。这些将导致对循环和混合的更好的理解。

Dale0136900Field and simulation studies will be used to determine where upwelled water originates, i.e. solely from the bottom boundary layer (BBL) or from a thicker region of the lower layer fluid, and where the displaced surface water goes, e.g. offshore in the the surface layer or, through subduction, to intermediate layers. Five dye studies, using fluorescene and rhodamine-WT, are proposed for the upwelling region over the Oregon shelf. Releases will occur in three different locations - beneath and inshore of the upwelling jet, in the BBL beneath the jet where onshore movement is expected, and inshore of the jet, just beneath the mixed layer but still in the Ekman layer, where offshore movement and possible subduction is expected. Dye will be tracked for 72 hours. The background environment will be defined by GLOBEC cruises, at least during the first field year. Three releases from the R/V Elakha will be traced during the first year. The second year will involve two larger releases from the R/V Wecoma. A version of the Princeton Ocean Model, configured for the region, will be run for comparison. Particle tracing techniques will be used to model the initial, small-scale dispersion. Both idealized situations and realistic modeling will be attempted. A 2-D ocean-going model will be used, in conjunction with buoyed GPS drifters, to track the subsurface dye patch after release. The results of the study will be a set of Lagrangian observations of cross-shelf transport pathways during upwelling. These will lead to improved understanding of circulation and mixing.