AON: Continuation of long-term observations of the Beaufort Gyre environmental changes in 2019-2020 to enhance understanding of the Arctic's impact on climate variability

博福特环流（BG）是北冰洋物理环境系统中一个独特的环流组成部分，反映了一系列与整个北极和全球气候系统有着重要相互关系的特定大气、海冰、海洋和生物地质生态条件。21世纪世纪最引人注目的北极观测结果之一是海冰范围和厚度的减少，以及BG地区淡水含量的增加。目前，对于这些变化及其对气候的影响，还没有足够的观测或理论来达成不同意见的共识。自2003年以来，BG夏季淡水含量增加了6，600立方公里。这不仅对北极海冰、海洋热力学和生态系统产生重要影响，而且北极可能释放的淡水量足以导致北大西洋的盐度异常，其幅度相当于20世纪70年代的大盐度异常，这可能会通过减少海洋纬向翻转环流来影响全球气候，并导致冷却。因此，BG系统是一个潜在的来源，迫使显着的气候变化，可能在十年的时间尺度。从该项目返回并通过项目网站免费分发并在NSF北极数据中心存档的数据将继续推进我们对北极环境变化的物理，化学和生物驱动因素的理解，它们与气候系统的关系以及与全球进程的联系。项目数据的长期时间序列将有助于数值模型的初始化和验证，并激发对北极科学问题的普遍兴趣。在该项目下获得的知识将继续对各种北极过程和气候研究、业务预报和其他北极研究计划至关重要，并将促进对北冰洋的进一步有价值的调查。该项目将继续扩大国际合作，促进研究人员和公众广泛进入北极。教育活动将包括培训研究生，为他们提供参加BG巡航的机会，并为他们提供BG数据分析方面的建议。北极建模和观测综合论坛项目和北极社区将继续使用项目数据，以验证和改进北极区域和全球模型，检验假设，并回答科学问题。博福特环流观测系统（BGOS）将在2019-2020年继续使用，以观察一组环境参数，锚定系泊和船上测量，以继续在标准地点的长期时间序列。每年夏天将继续与加拿大科学家合作，在船上进行覆盖整个BG的天气取样，以观察在观测期间某种意义上持续存在的气候环流状况的逆转。温度、盐度、氧气、营养物、钡、CFC和四氯化碳、碱度、总CO2、溶解无机碳、氚/3-He和δ-O-18将继续使用船上CTD/玫瑰花形装置在140 W、150 W、~ 75 N和~ 78 N下沿剖面进行测量和沿着分析。在CTD/玫瑰花形模型之间，将继续使用1 100米深度剖面的一次性CTD，以提高温度场和盐度场的空间分辨率。2018年重新部署的三个BGOS系泊系统将获得关于海水特性、海底压力、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进行评估，被认为值得支持的搜索.

The Beaufort Gyre (BG) is a unique circulation component within the Arctic Ocean's physical environmental system reflecting a set of specific atmospheric, sea-ice, oceanic and bio-geo-ecological conditions that have significant interrelationships with the Arctic-wide and global climate system. One of the most striking Arctic observations in the 21st century has been a reduction in both sea-ice extent and thickness, and an increase of freshwater content in the BG region. At present, there are insufficient observations or theories to reach a consensus among the different opinions about these changes and their impact on climate. The BG summer freshwater content has increased by 6,600 km3 since 2003. Not only does this have important consequences for Arctic sea-ice, ocean thermodynamics, and ecosystems, but a possible fresh water release from the Arctic of this magnitude is enough to cause a salinity anomaly in the North Atlantic with a magnitude comparable to the Great Salinity Anomaly of the 1970s, which could influence global climate by reducing the ocean meridional overturning circulation and result in cooling. Thus, the BG system is a potential source to force significant climate changes, likely at decadal time scales. Data returned from this project and distributed freely via the project website and archived with the NSF Arctic Data Center will continue to advance our understanding of the physical, chemical, and biological drivers of environmental change in the Arctic, their relationship to the climate system, and linkages to global processes. Long-term time series of project data will facilitate numerical model initialization and validation and stimulate general interest in Arctic science issues. The knowledge gained under this project will continue to be vital to a wide variety of Arctic processes and climate studies, to operational forecasting and other Arctic research programs, and will spur further valuable investigations of the Arctic Ocean. This project will continue to expand international cooperation and promote widespread access to Arctic for both researchers and the general public. Educational activities will include training of graduate students providing them the opportunity to participate in BG cruises and advising them in BG data analysis. The project data will continue to be used by the Forum for Arctic Modeling and Observational Synthesis (FAMOS) project and Arctic community to validate and improve Arctic regional and global models, test hypotheses, and answer scientific questions.The Beaufort Gyre Observing System (BGOS) will be continued throughout 2019-2020 to observe a set of environmental parameters using bottom-anchored moorings and shipboard measurements to continue the long-term time-series at standard locations. Ship-based synoptic sampling covering the entire BG will continue to be performed each summer in collaboration with Canadian scientists to observe reversal of the climatic circulation regime that has been persistent in one sense over the observation period. Temperature, salinity, oxygen, nutrients, barium, CFCs and carbon tetrachloride, alkalinity, total CO2, dissolved inorganic carbon, tritium/3-He and delta-O-18 will continue to be measured and analyzed along sections at 140W, 150W, ~75N and ~78N using a shipboard CTD/rosette. Between CTD/rosette casts, expendable CTDs that profile to 1100m depth will continue to be used to increase spatial resolution of the temperature and salinity fields. Three BGOS moorings redeployed in 2018 will acquire precise data on the variations of the vertical distribution of seawater properties, bottom pressures, and sea ice draft at the same scientifically important sites within the BG system and will be retrieved in 2020.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.