Carbon Sinks and Ocean Acidification in Canadian Coastal Waters

海洋从大气中吸收了大量的二氧化碳。这会减缓气候变化的速度，但会导致海洋酸化。海洋酸化对某些海洋生物有负面影响，包括一些重要的经济贝类和甲壳类物种。海水中二氧化碳的循环是复杂的，通常涉及其他温室气体，如甲烷(CH4)。该项目使用侧重于沿海社区参与的补充工具和方法来研究加拿大北冰洋和加拿大南部海洋的所有三个方面(二氧化碳、甲烷和海洋酸化)。在北极，人们对海洋二氧化碳和甲烷循环知之甚少。海冰被认为扮演着重要的角色，但我们缺乏基础研究来适当地将气体交换纳入冰冻海洋的模型中。河流也很重要，但目前还不确定它们向沿海海洋输送了多少二氧化碳和甲烷。该项目将使用我们与社区合作伙伴在剑桥湾(加拿大努纳武特)附近的一个小岛上合作建立的创新气象站，研究有海冰存在时的气体交换。通过直接测量这个站的二氧化碳交换，我们可以评估推动天然气运输的海冰和海洋条件。利用基于社区的采样方法，我们将收集北极湖泊、河流和河口溶解的二氧化碳和甲烷的测量结果。这些研究将使我们能够调查温室气体从淡水系统向海洋的移动，以及一旦它们到达那里会发生什么。该项目还将调查加拿大南部海岸的海洋酸化情况。尽管在一个非常不同的环境中，这项研究通过一个共同的主题(海水中的二氧化碳吸收)、共同的工具和对沿海社区的共同关注将这项研究与我们在北极的工作联系在一起。我们将与水产养殖运营商和其他收割机合作，测试低成本传感器检测危险海洋酸化事件的能力。我们还将开发新的样本采集方法，使“公民科学家”能够收集高质量的海洋酸化数据。通过将高质量的测量与收割机观察到的死亡事件联系起来，我们将调查加拿大水产养殖和野生渔业面临的新风险。这项研究的影响将是：1)改进北冰洋温室气体循环的预算，这是加拿大《巴黎协定》义务的重要组成部分；2)模拟存在海冰的气体交换的新方法，可适用于环极地北极和南极；3)监测和减轻海洋酸化影响的新战略。该研究计划的所有方面都依赖于沿海社区，并为有意义的合作提供了空间。该项目的目的是向土著(特别是因纽特人)社区学习，以找到促进社区优先事项和建设当地环境监测和研究能力的自然科学方法。

Oceans absorb a significant amount of carbon dioxide (CO2) from the atmosphere. This slows the rate of climate change, but causes ocean acidification. Ocean acidification has negative impacts on certain marine organisms, including some economically important species of shellfish and crustaceans. The cycling of CO2 in seawater is complex, and often involves other greenhouse gases like methane (CH4). This project uses complementary tools and approaches focused on coastal community engagement to study all three aspects (CO2, CH4, and ocean acidification) in both Arctic and southern Canadian seas. In the Arctic, marine CO2 and CH4 cycles are poorly understood. Sea ice is thought to play an important role, but we lack the fundamental studies to properly include gas exchange in models of icy oceans. Rivers are also important, but it is uncertain how much CO2 and CH4 they deliver to the coastal ocean. This project will study gas exchange in the presence of sea ice using an innovative weather station we have built in collaboration with community partners on a small island near Cambridge Bay (Nunavut, Canada). By directly measuring CO2 exchange at this station, we can assess the sea ice and ocean conditions that drive gas transport. Using a community-based sampling approach, we will collect measurements of dissolved CO2 and CH4 beneath Arctic lakes, in rivers, and in estuaries. These studies will allow us to investigate the movement of greenhouse gases from freshwater systems to the ocean, and what happens once they arrive there. This project will also investigate ocean acidification on southern Canadian coasts. Although in a very different environment, this research is linked to our Arctic work through a common topic (CO2 absorption in seawater), common tools, and a common focus on coastal communities. We will work with aquaculture operators and other harvesters to test the ability of low-cost sensors to detect dangerous ocean acidification events. We will also develop new methods of sample collection that will enable "citizen scientists" to collect high quality ocean acidification data. By linking high quality measurements with mortality events observed by harvesters, we will investigate the emerging risks to aquaculture and wild fisheries in Canada. The impacts of this research will be: 1) improved budgets of greenhouse gas cycles in Arctic seas, a critical component of Canada's Paris Agreement obligations; 2) new methods for modeling gas exchange in the presence of sea ice that can be applied to the circumpolar Arctic and Antarctic; 3) new strategies for monitoring and mitigating the effects of ocean acidification. All aspects of this research program rely on coastal communities, and provide space for meaningful collaborations. The project is designed to learn from Indigenous (particularly Inuit) communities to find ways for natural science to advance community priorities and build local capacity for environmental monitoring and research.