Greenhouse Gas Dynamics Across the Land-to-Ocean Continuum in the Canadian Archipelago

当前和未来的气候变暖有可能影响北极甲烷的循环，该地区对全球甲烷收支的贡献仍然受到限制。永久冻土的融化以及冰层的融化有可能调动大量的甲烷。这个项目的重点是了解跨越加拿大北部陆地-海洋连续体的湖泊、河流和海湾之间的联系。来自陆地和淡水系统的甲烷和二氧化碳可以在春季融化期间被动员起来，并迅速输送到沿海海洋。调查人员将使用无人驾驶飞行器来研究这些气体的命运，因为它们通过小型河流网络输送到沿海海洋，然后随着海冰的破裂而释放出来。该项目的更广泛影响包括为北极研究开发新技术，培训一名极地实地工作和工程方面的女研究生，以及与当地土著社区接触。北极淡水水体对全球甲烷预算的贡献很少受到限制。该项目将使用一个尖端的自主水面平台来测量加拿大剑桥湾表层水域中溶解的甲烷、二氧化碳、盐度、硝酸盐和氧气。研究人员将在春季新生周围的几周内，通过两个野外季节的密集空间和时间采样，量化甲烷和二氧化碳快速释放的规模。具体目标是：描述温室气体在淡水期间从陆地水生系统进入沿海海洋的快速横向脉冲的特征；确定甲烷和二氧化碳在冰下积累的程度；量化快速排出气体到大气层的地理范围和速率；关闭剑桥湾的物质平衡，以确定输送到沿海海洋的大部分甲烷和二氧化碳是否向外排出气体。调查人员还将为携带传感器技术的自动驾驶车辆提供概念证明，该技术可以在危险或恶劣的环境中扩展我们的空间和时间采样能力。这一奖项反映了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。

Current and future warming has the potential to impact the cycling of methane in the Arctic, and the contribution of the region to the global methane budget remains poorly constrained. Thawing of permafrost, as well as melting of ice, has the potential to mobilize significant quantities of methane. This project focuses on understanding the connection between lakes, rivers, and bays across the land-ocean continuum in northern Canada. Methane and carbon dioxide from terrestrial and freshwater systems can be mobilized during the spring thaw and rapidly transported into the coastal ocean. The investigators will use unmanned vehicles to study the fate of these gases as they are transported via small river networks to the coastal ocean and subsequently outgassed as sea ice breaks up. Broader impacts of this project include developing new technology for Arctic research, training a female graduate student in polar field work and engineering, and engagement with local indigenous communities.The contribution of Arctic fresh water bodies to the global methane budget is poorly constrained. This project will use a cutting-edge autonomous surface platform to measure dissolved methane, carbon dioxide, salinity, nitrate, and oxygen in surface waters of Cambridge Bay, Canada. The investigators will quantify the magnitude of the rapid burst of outgassing of methane and carbon dioxide with two field seasons of intensive spatial and temporal sampling during the weeks surrounding the spring freshet. The specific objectives are to: characterize the rapid lateral pulse of greenhouse gases entering the coastal ocean from terrestrial aquatic systems during the freshet; determine the extent to which methane and carbon dioxide accumulates under ice; quantify the geographical extent and rate of rapid outgassing to the atmosphere; and close a mass balance of the Cambridge Bay to determine if the majority of methane and carbon dioxide delivered to the coastal ocean outgasses. The investigators will also provide proof of concept for autonomous vehicles carrying sensor technology that can expand our spatial and temporal sampling capability in dangerous or harsh environments.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.