U.S. GLOBEC: GEORGES BANK PHASE III Cross-Frontal Exchange Studies at the Base of the Tidally Mixed Front using an Injected Dye Tracer

美国GLOBEC：乔治银行第三阶段使用注入染料示踪剂在潮汐混合锋底部进行的跨锋交换研究。霍顿乔治浅滩被潮汐混合锋包围。 这条战线在维持河岸高生物生产力方面的作用（它是屏障还是管道？）还没有被完全理解。 有证据表明，跨锋面环流可能是至关重要的调节通量的营养物质和颗粒，如浮游动物和鱼苗，在银行，这两个都有助于这个生态系统的高生产力。 我们建议使用一个有目的地注入染料，直接测量的混合和跨银行流通的潮汐前沿的脚，在银行的流量预计是最大的。 最近在新英格兰大陆架上的断架前沿证明了荧光染料示踪剂在此类研究中的实用性。 染料追踪不断移动的锋面边界的能力使其成为研究乔治银行的一种特别强大的技术。 由于染料补丁的传播是指的温度场，确定了前，复杂性所引入的锋面位移，不规则的底部地形，和波动，强烈的沿岸流是避免和跨锋面环流和混合是明确的定义。 染料示踪剂测量将直接有助于我们了解使乔治银行这样一个高生产力的海洋生态系统的过程。 这种理解是必要的，以便管理这一资源，以保持和利用其对国家经济的最佳贡献。 还需要了解潜在气候变化对这一生态系统的影响，以预测这种变化将如何影响这一资源和其他宝贵的海洋资源。 该项目通过展示染料示踪剂的独特用途，将推动这项技术在海洋研究中的未来应用的发展。

U.S. GLOBEC: GEORGES BANK PHASE III Cross-frontal exchange studies at the base of the tidally mixed front using an injected dye tracerRobert W. Houghton Georges Bank is surrounded by a tidally mixed front. The role of this front in maintaining the high biological productivity on the Bank (Is it a barrier or conduit?) is not fully understood. There is evidence that cross-frontal circulation may be critical for modulating the flux of nutrients and the retention of particles, such as zooplankton and fish larvae, on the Bank both of which contributes to the high productivity of this ecosystem. We propose to use a purposefully injected dye to directly measure the mixing and cross-bank circulation at the foot of the tidal front where on-bank flux is expected to be greatest. The utility of a fluorescent dye tracer for such studies has recently been demonstrated at the shelfbreak front on the New England Shelf. The ability of the dye to follow a constantly moving frontal boundary makes it a particularly powerful technique for studies on Georges Bank. Since the spreading of the dye patch is referenced to the temperature field that defines the front, the complexity introduced by frontal displacements, irregular bottom topography, and a fluctuating, strong along-bank flow is avoided and the cross-frontal circulation and mixing is unambiguously defined. The dye tracer measurements will contribute directly to our understanding of the processes that make Georges Bank such a highly productive marine ecosystem. This understanding is necessary in order to manage this resource to maintain and exploit its optimum contribution to the nation's economy. The understanding is also necessary to anticipate how changes in the forcing of this ecosystem by potential climate changes will affect this, and other, valuable marine resources. This project by demonstrating the unique utility of the dye tracer will advance the development of this technology for future applications in marine research.