Monitoring the Western Arctic Boundary Current in a Warming Climate: Atmospheric Forcing and Oceanographic Response

气候变暖时监测北极西部边界流：大气强迫和海洋学响应

• 批准号: 2135537
• 负责人: Robert Pickart
• 金额: $ 237.86万
• 依托单位: Woods Hole Oceanographic Institution
• 依托单位国家: 美国
• 项目类别: Continuing Grant
• 财政年份: 2022
• 资助国家: 美国
• 起止时间: 2022-04-01 至 2027-03-31
• 项目状态: 未结题
• 来源: https://www.nsf.gov/awardsearch/showAward?AWD_ID=2135537&HistoricalAwards=false
• 关键词: Monitoring; Western; Arctic; Boundary; Current

Due to the changing climate, the Arctic Ocean is experiencing profound changes. Pack-ice is melting, water is warming, storms are becoming stronger and more frequent, and basic circulation patterns are being altered. This project focuses on the fate of the Pacific water that enters the Arctic Ocean through the Bering Strait, the narrow passage between the US and Russia. 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 fresh water to the Arctic Ocean. After the Pacific-origin water crosses the Chukchi Sea, north of Bering Strait, some of it forms a current that flows eastward along the edge of the adjacent Beaufort Sea. As part of the project, a mooring will be maintained in the center of this current to measure its physical and biological properties. The mooring has been deployed (with a few gaps) since 2002. By extending the measurements for another four years, this provides the chance to document and understand how this important part of the Arctic system is responding to the drastic environmental changes – including the varying atmospheric conditions and evolving source waters from Bering Strait. The data obtained by the mooring, along with the shipboard measurements collected when the mooring is serviced, will continue to be widely used by the scientific community in both observational and modeling studies. A graduate student will be supported by the project, and community outreach will be undertaken during one of the expeditions in order to engage the public. The AON monitoring mooring is situated at 152°W near the Beaufort Sea shelfbreak, roughly 150 km downstream of Barrow Canyon – the main Pacific water outflow point from the Chukchi Sea. It will be deployed from fall 2022 to fall 2026, which will extend the timeseries to 21 years. The mooring measures the velocity of the water column, the thickness and velocity of the pack ice, and the temperature, salinity, and pressure throughout the water column. Chlorophyll fluorescence and nitrate are measured at the top of the mooring, and a passive acoustic recorder documents marine mammal calls. Zooplankton concentration is estimated using the ADCP backscatter data. Collectively, this information enables determination of how much water, heat, nutrients, chlorophyll, and freshwater are transported by the current, and assessment of how much exchange occurs between the interior of the Arctic Ocean and the boundary waters. This includes wind-driven upwelling and downwelling that take place throughout the year along the Beaufort slope, and appear to be increasing as the climate warms. During the biennial cruises to service the mooring, a hydrographic/velocity survey of the boundary current system is carried out to obtain a large-scale context for the mooring timeseries. The shipboard sampling includes occupations of some of the Distributed Biological Observatory transects. As in the past, the biennial cruises will provide a platform for a broad array of interdisciplinary projects.This award reflects NSF's statutory mission and has been deemed worthy of support through evaluation using the Foundation's intellectual merit and broader impacts review criteria.

由于气候变化，北冰洋正在经历深刻的变化。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。这个项目的重点是通过白令海峡进入北冰洋的太平洋水的命运，白令海峡是美国和俄罗斯之间的狭窄通道。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。在太平洋起源的水穿过白令海峡以北的楚科奇海后，其中一部分形成一股水流，沿着邻近的博福特海边缘向东流动。作为该项目的一部分，将在该水流的中心保留一个系泊装置，以测量其物理和生物特性。自2002年以来，已部署了系泊设备（有一些间隙）。通过将测量时间延长四年，这为记录和了解北极系统的这一重要部分如何应对剧烈的环境变化提供了机会-包括变化的大气条件和白令海峡不断变化的源沃茨。科学界将继续在观测和模拟研究中广泛使用系泊系统获得的数据，沿着以及系泊系统维修时收集的船上测量数据。该项目将支持一名研究生，并将在其中一次探险期间开展社区外联活动，以吸引公众参与。 AON监测系泊位于博福特海陆架坡附近152°W，巴罗峡谷下游约150 km处，巴罗峡谷是楚科奇海的主要太平洋水流出点。它将从2022年秋季部署到2026年秋季，这将把时间序列延长到21年。系泊测量水柱的速度，浮冰的厚度和速度，以及整个水柱的温度，盐度和压力。叶绿素荧光和硝酸盐是在系泊顶部测量的，一个被动声学记录器记录了海洋哺乳动物的叫声。浮游动物浓度估计使用ADCP后向散射数据。总的来说，这些信息可以确定水流输送了多少水、热量、营养物质、叶绿素和淡水，并评估北冰洋内部和边界沃茨之间发生了多少交换。这包括沿着博福特斜坡全年发生的风驱动的上升流和下降流，并且随着气候变暖而增加。在两年一次的系泊服务巡航期间，对边界流系统进行水文/流速调查，以获得系泊时间序列的大规模背景。船上取样包括一些分布式生物观测断面的职业。与过去一样，两年一次的巡航将为广泛的跨学科项目提供一个平台。该奖项反映了NSF的法定使命，并通过使用基金会的知识价值和更广泛的影响审查标准进行评估，被认为值得支持。

项目成果

Eddies and the Distribution of Eddy Kinetic Energy in the Arctic Ocean

北冰洋的涡流和涡动能的分布

• DOI: 10.5670/oceanog.2022.122
• 发表时间: 2022
• 期刊: Oceanography
• 影响因子: 2.8
• 作者: von Appen, Wilken-Jon;Baumann, Till;Janout, Markus;Koldunov, Nikolay;Lenn, Yueng-Djern;Pickart, Robert;Scott, Robert;Wang, Qiang
• 通讯作者: Wang, Qiang

Coastal upwelling enhances abundance of a symbiotic diazotroph (UCYN-A) and its haptophyte host in the Arctic Ocean

沿海上升流增强了北冰洋共生固氮生物（UCYN-A）及其附着菌宿主的丰度

• DOI: 10.3389/fmars.2022.877562
• 发表时间: 2022
• 期刊: Frontiers in Marine Science
• 影响因子: 3.7
• 作者: Selden, Corday R.;Einarsson, Sveinn V.;Lowry, Kate E.;Crider, Katherine E.;Pickart, Robert S.;Lin, Peigen;Ashjian, Carin J.;Chappell, P. Dreux
• 通讯作者: Chappell, P. Dreux

Paralytic shellfish toxins in Alaskan Arctic food webs during the anomalously warm ocean conditions of 2019 and estimated toxin doses to Pacific walruses and bowhead whales

• DOI: 10.1016/j.hal.2022.102205
• 发表时间: 2022-03-03
• 期刊: HARMFUL ALGAE
• 影响因子: 6.6
• 作者: Lefebvre, Kathi A.;Fachon, Evangeline;Siddon, Elizabeth
• 通讯作者: Siddon, Elizabeth

Harmful Algal Blooms in the Alaskan Arctic: An Emerging Threat as the Ocean Warms

阿拉斯加北极地区有害藻类大量繁殖：海洋变暖带来的新威胁

• DOI: 10.5670/oceanog.2022.121
• 发表时间: 2022
• 期刊: Oceanography
• 影响因子: 2.8
• 作者: Anderson, Donald;Fachon, Evangeline;Hubbard, Katherine;Lefebvre, Kathi;Lin, Peigen;Pickart, Robert;Richlen, Mindy;Sheffield, Gay;Van Hemert, Caroline
• 通讯作者: Van Hemert, Caroline

Alexandrium on the Alaskan Beaufort Sea shelf: Impact of upwelling in a warming Arctic

阿拉斯加波弗特海大陆架上的亚历山大：北极变暖中上升流的影响

• DOI: 10.1016/j.hal.2022.102346
• 发表时间: 2022
• 期刊: Harmful Algae
• 影响因子: 6.6
• 作者: Einarsson, Sveinn V.;Lowry, Kate E.;Lin, Peigen;Pickart, Robert S.;Ashjian, Carin J.;Chappell, P. Dreux
• 通讯作者: Chappell, P. Dreux