AON: Monitoring the Western Arctic Boundary Current in a Warming Climate

随着地球气候在过去几十年里变暖，我们的星球经历了许多深刻的变化。没有任何地方的变化比北冰洋更明显，也没有发生得那么快。浮冰正在融化，海水正在变暖，风暴变得越来越强，越来越频繁，基本的环流模式正在改变。我们的项目重点关注通过白令海峡进入北冰洋的太平洋海水的命运。太平洋水在北极西部生态系统中起着至关重要的作用。在冬季，流入的冷水提供了营养物质，刺激了处于食物链底层的浮游植物的生长。在夏季，温暖的海水融化了浮冰，为北冰洋提供了淡水。海水穿过白令海峡以北的楚科奇海后，其中一部分在陆架边缘形成一条狭窄的海流，向东流动。作为我们项目的一部分，我们将继续保持一个定位在当前中心的系泊设备，以测量其物理和生物特性。该系泊装置自2002年以来一直在部署（有一些间隙），在此期间，它测量到了需要在不断变化的北极系统的背景下进行分析的显着变化。此外，当我们维修系泊设备时，我们将对当前和邻近沃茨进行船上调查，以提供对太平洋水域命运的更大范围的看法。 监测系泊位于博福特海陆架断裂附近的152 oW处，大约在Pt下游150 km处。巴罗。它将从2016年秋季部署到2018年秋季，为期两年。这将把该地点的时间序列延长到13年。系泊设备使用两个ADCP记录水柱和浮冰的速度，并使用一系列沿钢丝沿着分布的MicroCats测量温度、盐度和压力。叶绿素荧光和硝酸盐将在35米处（系泊设备的顶部浮子处）进行测量，位于系泊设备底部附近的被动声学记录仪将记录海洋哺乳动物的叫声。将使用ADCP后向散射数据估计浮游动物浓度。除此之外，这将使我们能够确定有多少水、热量、营养物质、叶绿素和淡水被海流输送，更重要的是，评估北冰洋内部和边界沃茨之间发生了多少交换。沿博福特斜坡的上升流在沿着的所有季节都有发生，而且随着气候变暖，上升流似乎也在增加。系泊非常适合量化上升流以及发生的任何下降流。船上采样将包括对分布式生物观测站的一些断面进行采样，这将有助于这些正在进行的时间序列。

As Earth's climate has warmed over the past few decades, our planet has experienced a multitude of profound changes. Nowhere have the changes been more pronounced, nor happened as quickly, as in the Arctic Ocean. Pack-ice is melting, water is warming, storms are becoming stronger and more frequent, and basic circulation patterns are being altered. Our project focuses on the fate of the Pacific water that enters the Arctic Ocean through the Bering Strait. Pacific water plays a critical role in the western Arctic ecosystem. In wintertime the cold inflowing water provides nutrients that spur the growth of phytoplankton at the base of the food chain. In summertime, the warm water melts pack ice and provides freshwater to the Arctic Ocean. After the water crosses the Chukchi Sea, north of Bering Strait, some of it forms a narrow current at the edge of the shelf and flows eastward. As part of our project we will continue to maintain a mooring positioned in the center of the current to measure its physical and biological properties. The mooring has been deployed (with a few gaps) since 2002, and during this time it has measured striking changes that need to be placed in the context of the evolving Arctic system. In addition, we will carry out shipboard surveys of the current and adjacent waters when we service the mooring, to provide a larger-scale view of the fate of the Pacific water. The monitoring mooring is situated at 152oW near the Beaufort Sea shelf break, roughly 150 km downstream of Pt. Barrow. It will be deployed for two years from fall 2016 to fall 2018. This will extend the time series at this location to 13 years. The mooring records the velocity of the water column and pack ice using two ADCPs, and measures temperature, salinity, and pressure using a series of MicroCats spaced along the wire. Chlorophyll fluorescence and nitrate will be measured at 35 m (at the top float of the mooring), and a passive acoustic recorder situated near the base of the mooring will record marine mammal calls. Zooplankton concentration will be estimated using the ADCP backscatter data. Among other things, this will allow us to determine how much water, heat, nutrients, chlorophyll, and freshwater are transported by the current, and, importantly, assess how much exchange occurs between the interior of the Arctic Ocean and the boundary waters. Upwelling occurs during all seasons along the Beaufort slope, and it appears to be increasing as the climate warms. The mooring is ideally suited to quantify the upwelling, as well any downwelling that occurs. The shipboard sampling will include sampling of some of the Distributed Biological Observatory transects, which will contribute to those ongoing time series.