Atlantic BiogeoChemical fluxes (ABC)

北大西洋在全球碳循环中发挥着举足轻重的作用，它储存了化石燃料燃烧时释放到大气中的碳，并支持有机物的下沉通量。我们对亚热带水平海洋通量如何对这些过程做出贡献的理解在很大程度上是基于每隔5年在北纬24度进行的船上考察。以这个间隔进行抽样不足以解决和理解水平转移在调节这些过程中所起的作用。来自系泊仪器在北纬26.5度的物理性质的详细时间序列表明，这些通量的变化将在一系列时间尺度上发生。一旦测量到这种可变性，我们几乎不可避免地会改变对北大西洋副热带环流在全球碳循环中所起作用的理解。在这项提案中，我们将通过在北纬26.5度的大西洋彼岸部署新的化学传感器和采样器来解决这些问题。我们将使用他们提供的数据来计算营养物质和无机碳的通量的时间序列，包括人类活动释放到大气中的碳，跨越26.5北纬。我们将采用分层方法，先后使用现有观测，然后是新的氧气观测，并最终直接观测碳和营养物质，以确定我们方案的每个后续阶段提供的附加值。我们将把我们的直接通量计算与其他观测和模型一起解释为对北大西洋预算的贡献，以评估海洋通量如何控制北大西洋在全球碳循环中所起作用的强度和变异性。

The North Atlantic Ocean plays a pivotal role in the global carbon cycle, by storing carbon released into the atmosphere when fossil fuels are burned, and by supporting the sinking flux of organic matter. Our understanding of how horizontal oceanic fluxes in the subtropics contribute to these processes is largely based on shipboard expeditions which occur every 5 years at 24N. Sampling at that interval is insufficient to resolve and understand the role that horizontal transfers play in regulating these processes. Detailed time-series of physical properties at 26.5N from moored instruments suggest that variability in these fluxes will be occurring on a range of timescales. Once this variability is measured, it is almost inevitable that we will modify our understanding of the role the North Atlantic subtropical gyre plays in the global carbon cycle. In this proposal we will address these issues by deploying new chemical sensors and samplers across the Atlantic at 26.5N. We will use the data they provide to calculate time-series of fluxes of nutrient and inorganic carbon, including carbon released to the atmosphere by mans activities, across 26.5N. We will adopt a hierarchical approach, successively using existing observations, then new oxygen observations and ultimately direct observations of the carbon and nutrients in order to identify the added value each successive stage of our programme provides. We will interpret our direct flux calculations as contributions to the North Atlantic budget in conjunction with other observations and models, to assess how oceanic fluxes control the strength and variability of the role the North Atlantic plays in the global carbon cycle.