An Observational Array for High Resolution, Year-round Measurements of Volume, Freshwater, and Ice Flux Variability in Davis Strait

这项研究将使用一个综合观测系统，该系统将全年测量戴维斯海峡的体积、液态淡水和冰通量。流经海峡的通量代表加拿大群岛经巴芬湾向南转运过程中受到陆地输入和海洋过程影响的净综合流量。这项研究将是一项国际协调努力的一部分，目的是量化(并最终监测)连接北冰洋和大西洋的通量的可变性，并了解北极和次北极在操纵十年尺度气候多变性方面所发挥的作用。该系统将采用补充技术，将成熟技术与自动滑翔机的最新发展(目前正在执行其第一次扩大的科学任务)结合起来，以处理通过戴维斯海峡的水流的所有方面，包括一些以前在技术上不可行的测量方法。拟议系统的组件包括：一个稀疏的地下系泊设备阵列，每个设备上都装有一个向上俯视的声纳、一个声学多普勒海流剖面仪(ADCP)和一个电导率-温度(CT)传感器。这些数据将提供上层洋流、冰层速度和冰层厚度的时间序列。然后，这些测量将被用于估计淡水通量的冰成分，为根据Seaglider水文剖面计算的地转切变提供绝对速度参考，并为低频通量计算得出误差估计。装有ADCP和CT传感器的抗拖网和抗冰山海底着陆器将部署在巴芬和格陵兰大陆架上，以量化与强大而狭窄的沿海气流有关的可变性。声学导航的Seaglider将提供海峡两岸全年重复的高分辨率水文区段。在观测系统中实施的新兴技术和现有技术相结合，可作为准确长期监测季节性或永久性冰覆盖的高纬度环境中淡水和冰通量的原型。能够在冰雪覆盖的环境中延长任务的声导航自动滑翔机将提供一种重要的新观测工具，为密集的测量计划打开高纬度海洋的重要区域。

This study will use an integrated observing system that will provide year-round measurements of volume, liquid freshwater and ice fluxes across Davis Strait. Fluxes through the Strait represent the net integrated Canadian Archipelago through flow, modified by terrestrial inputs and oceanic processes during its southward transit through Baffin Bay. This study will be part of a coordinated international effort to quantify (and eventually monitor) the variability of fluxes connecting the Arctic and Atlantic Oceans and to understand the role played by the Arctic and sub-Arctic in steering decadal scale climate variability, The system will employ complementary techniques, combining mature technologies with recent developments in autonomous gliders (presently undertaking their first extended science missions) to address all aspects of flow through Davis Strait, including some measurements that have not previously been technologically feasible. The components of the proposed system include: A sparse array of subsurface moorings, each instrumented with an upward looking sonar, an Acoustic Doppler Current Profiler (ADCP) and a single conductivity-temperature (CT) sensor. These will provide a time series of upper ocean currents, ice velocity and ice thickness. These measurements will then be used to estimate the ice component of freshwater flux, provide an absolute velocity reference for geostrophic shears calculated from Seaglider hydrographic sections, and derive error estimates for lower-frequency flux calculations. Trawl and iceberg resistant bottom landers, instrumented with ADCPs and CT sensors, will be deployed across the Baffin and Greenland shelves to quantify variability associated with strong, narrow coastal flows. Acoustically navigated Seagliders will provide year-round, repeated, high-resolution hydrographic sections across the Strait. The combination of emerging and existing technologies implemented in the observing system may serve as a prototype for accurate long-term monitoring of freshwater and ice fluxes in high latitude environments subject to seasonal or permanent ice cover. Acoustically navigated autonomous gliders capable of extended missions in ice covered environments will provide a significant new observational tool, opening important regions of high latitude oceans to intensive measurement programs.