Collaborative Research: Quantifying microbial controls on the annual cycle of methane and oxygen within the ultraoligotrophic Central Arctic during MOSAiC

随着多年的海冰让位于新的季节性海冰体系，北冰洋中部正在迅速变化，这些区域变化对全球气候以及整个北极系统都有重要影响。作为北极气候研究多学科漂流观测站(MOSAIC)的一部分，调查人员将使用冻结在极地冰层中的考察船作为采样平台，重点研究海冰对整个年度周期中氧气和甲烷的吸收和释放的影响。结合马赛克合作者的其他观察，这些数据将使研究人员能够建立一个详细的碳和能量跨季节流动的概念模型，并改进解释更广泛的北极系统行为的数字模型。此外，他们将使用基因组技术对这一未被研究的地区的微生物动态和多样性有一个新的理解。这项工作的更广泛影响包括对早期职业科学家的支持，作为MASIC计划的一部分的重大国际合作，以及对博士后科学家和本科生的培训。公众外展将包括观看西北极地航道纪录片在加利福尼亚州圣地亚哥和里约热内卢普罗维登斯的冰冻痴迷，然后是关于极地探索、生态和变化的小组讨论。该项目的目标是确定氧气和甲烷的生产和吸收背后的生物和物理驱动因素，在营养贫乏的北极中部建立这些关键气体的代谢平衡。调查人员将利用为期一年的研究北极气候的国际多学科漂流观测站(MOSAIC)探险提供的独特机会，通过全年对氧气和Ar的测量以及甲烷氧化和甲烷浓度和同位素比率的产生来确定群落净生产量。他们将测量细菌和群落的呼吸、细菌产量和微生物群落结构，并分析基因表达，以确定与表层海洋甲烷生产相关的基因、生物和途径。结果将被用于使用MITgcm北极区域模型模拟海洋甲烷循环，并改进区域北极系统模型(RASM)的生物地球化学成分。该奖项反映了NSF的法定使命，并通过使用基金会的智力优势和更广泛的影响审查标准进行评估，被认为值得支持。

The central Arctic Ocean is changing rapidly as multiyear sea ice gives way to a new seasonal sea ice regime, and these regional shifts have important implications for global climate as well as the entire Arctic system. As part of the Multidisciplinary drifting Observatory for the Study of Arctic Climate (MOSAiC), the investigators will use a research vessel frozen into polar ice as a sampling platform to focus on the influence of sea ice on the uptake and release of oxygen and methane across a full annual cycle. Combined with other observations made by MOSAiC collaborators, these data will allow the investigators to build a detailed conceptual model of carbon and energy flow across seasons and improve numerical models explaining the behavior of the broader Arctic system. In addition, they will use genomic techniques to gain a new understanding of microbial dynamcis and diversity in this understudied region. The broader impacts of this work include support for early-career scientists, significant international collaboration as part of the MOSAiC program, and training for postdoctoral scientists and undergraduate students. Public outreach will include viewings of the Northwest Polar Passage documentary Frozen Obsession in San Diego, CA, and Providence, RI, followed by panel discussions on polar exploration, ecology, and change. The goal of this project is to identify the biological and physical drivers underlying the production and uptake of oxygen and methane, establishing the metabolic balance of these key gases in the oligotrophic Central Arctic. The investigators will take advantage of the unique opportunity afforded by the international, year-long Multidisciplinary drifting Observatory for the Study of Arctic Climate (MOSAiC) expedition to determine net community production from year-round measurements of oxygen and argon, as well as methane oxidation and production from methane concentration and isotopic ratios. They will measure bacterial and community respiration, bacterial production, and microbial community structure, and analyze gene expression to identify the genes, organisms, and pathways associated with methane production in the surface ocean. Results will be used to model the oceanic methane cycle using the MITgcm Arctic Regional Model and improve the biogeochemical components of the Regional Arctic System Model (RASM).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.