The Eastern Eurasian Basin: Rerouting fresh water between the Eastern and Western Arctic in response to atmospheric and oceanic forcings

东部欧亚盆地：根据大气和海洋强迫改变北极东部和西部之间的淡水路线

• 批准号: 1724523
• 负责人: Igor Polyakov
• 金额: $ 513.02万
• 依托单位: University of Alaska Fairbanks Campus
• 依托单位国家: 美国
• 项目类别: Continuing Grant
• 财政年份: 2020
• 资助国家: 美国
• 起止时间: 2020-05-15 至 2027-04-30
• 项目状态: 未结题
• 来源: https://www.nsf.gov/awardsearch/showAward?AWD_ID=1724523&HistoricalAwards=false
• 关键词: Eastern; Eurasian; Basin; Rerouting; fresh

Large amounts of freshwater from rivers enter the Arctic Ocean through the eastern Eurasian Basin (EEB) during the spring, summer, and fall. The EEB acts like a railroad switch, controlling where that freshwater moves within the Arctic Ocean and sub-polar seas. The freshwater input from rivers is increasing as the Arctic warms. This makes understanding processes in the Eastern Eurasian Basin especially important. This study aims to understand how the EEB redistributes ice and fresh water between the eastern and western Arctic in response to changes in the atmosphere. Three biennial cruises, planned for August-September, will take measurements between Franz Josef Land and the central East Siberian Sea, following a path that moves from shallow water to the deep sea. The sampling program connects observations using moorings, ship sampling, and drifters. These efforts will inform the scientific community and the broader public about major changes in the EEB that could impact the state of Arctic ice cover, marine ecosystems, and areas further south. The proposed observations are also important for developing estimates for future summer sea-ice conditions, which are valuable information for national security, the transportation industry, and weather forecasting. A graduate student and a K-12 teacher will join the cruises to engage in research. Together with a researcher, they will share and reach out to classrooms and the general public. The project will support one graduate student. The eastern Eurasian Basin (EEB), including its shelves distributes ice and Arctic riverine water between the Eastern and Western Arctic. This provides the shortest pathway for Arctic freshwater to the sub-polar seas where weak stratification leads to deep convection, a key mechanisms of global thermohaline circulation. Recent observations have captured unprecedented changes in the EEB, likely representing a fundamental shift to a new, less stable, more dynamic mode. The goal of our study is to develop a comprehensive and quantitative understanding of how the EEB functions, accumulating and releasing major Arctic riverine transports and redistributing ice and fresh water between the Eastern and Western Arctic in response to atmospheric and oceanic forcings. Quantifying EEB freshwater inventories and transports, following alternating atmospheric regimes, will be critical to future understanding of the Arctic Ocean's oceanography. This program will provide sustained measurements in critical areas; data and products, critically-needed benchmarks for Arctic satellite sea-ice and altimeter measurements, will be publicly available.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.

在春季、夏季和秋季，大量淡水从河流通过欧亚盆地东部（EEB）进入北冰洋。EEB就像一个铁路开关，控制着北冰洋和次极地海洋中淡水的流动。随着北极变暖，来自河流的淡水输入正在增加。这使得了解欧亚盆地东部的过程尤为重要。这项研究旨在了解EEB如何在北极东部和西部之间重新分配冰和淡水，以应对大气的变化。计划于8月至9月进行的三次两年一次的巡航将在弗朗茨约瑟夫地和东西伯利亚海中部之间进行测量，沿着从浅水到深海的路径移动。采样程序将使用系泊、船舶采样和漂流器的观测结果连接起来。这些努力将向科学界和更广泛的公众通报EEB的重大变化，这些变化可能影响北极冰盖、海洋生态系统和更南部地区的状况。拟议的观测结果对估计未来夏季海冰状况也很重要，这对国家安全、运输业和天气预报都是有价值的信息。一名研究生和一名K-12教师将加入游轮从事研究。他们将与一名研究人员一起分享并接触教室和公众。该项目将资助一名研究生。欧亚海盆东部，包括其大陆架，将冰和北极河水分布在北极东部和西部之间。这为北极淡水进入次极地海洋提供了最短的通道，在次极地海洋中，弱分层导致深层对流，这是全球温盐环流的一个关键机制。最近的观测已经捕捉到了EEB前所未有的变化，可能代表着向一种新的、不太稳定的、更动态的模式的根本转变。我们研究的目标是全面和定量地了解EEB如何发挥作用，积累和释放主要的北极河流运输，并在北极东部和西部之间重新分配冰和淡水，以响应大气和海洋强迫。量化EEB淡水库存和运输，交替的大气制度，将是至关重要的未来了解北冰洋的海洋学。该计划将提供关键领域的持续测量;数据和产品，北极卫星海冰和高度计测量的关键基准，将公开提供。该奖项反映了NSF的法定使命，并已被认为值得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的支持。