GLOBEC-NEP: Topographic Control of Mesoscale Variability in the Gulf of Alaska

本项目研究阿拉斯加湾大陆架的物理和生物分布和过程及其对幼鲑鱼补充的影响。 该项目最重要的主题是，沿大陆架和跨大陆架的中尺度结构是由海流的测深控制造成的。 与此相关的物理海洋学特征是阿拉斯加沿岸流，其在苏厄德涡和苏厄德反涡，陆架前，斜坡涡和曲流和深流离岸游览。这些特征影响到深水浮游动物的运输和分布，而浮游动物据称是幼鲑鱼的重要食物来源，并可能决定幼鲑鱼的生存。正在使用一个起伏的水下拖曳飞行器（SeaSoar）不断绘制盐度、温度、深度和生物光学特性的地图。正在使用类似的传感器连续测量上述表面样品、营养物质和叶绿素荧光。PI正在使用声学多普勒海流剖面仪（ADCP）测量150米深处的沿着和跨航迹流速。 研究员将用现场的盐度、温度、营养物和浮游植物样本对上述数据进行校准。 这项研究的更广泛的影响包括培训两名博士生在多学科海洋学和更好地了解海洋学的影响对阿拉斯加湾鲑鱼变异的影响。

This project addresses studies of the physical and biological distributions and processes and their effect on juvenile salmon recruitment on the Gulf of Alaska shelf. The overriding theme of the project is that along-shelf and cross-shelf mesoscale structures are due to bathymetric control of the currents. Physical oceanographic characteristics associated with this are the Alaska Coastal Current, its offshore excursions in the Seward Eddy and Seward Counter Eddy, the shelfbreak front, slope eddies and meanders and the deep flow. These features affect the transport and distribution of deep-water zooplankton that are alleged to be an important food source for juvenile salmon and may determine their survival. An undulating, underwater, towed vehicle (SeaSoar) is being used to continuously map salinity, temperature, depth and bio-optical properties. Surface samples of the above, nutrients, and chlorophyll fluorescence are being measured continuously using similar sensors. The PIs are using an Acoustic Doppler Current Profiler (ADCP) to measure along- and cross-track current velocities to 150 m depth. The PIs will calibrate the above with on-station samples of salinity, temperature, nutrients and phytoplankton. The broader impacts of this study include training of two PhD students in multidisciplinary oceanography and a better understanding of the effects of oceanographic effects on salmon variability in the Gulf of Alaska.