Capturing Oceanic Submesoscales, Stirring, and Mixing with Sound and Simulations

通过声音和模拟捕捉海洋亚尺度、搅拌和混合

• 批准号: MR/X035611/1
• 负责人: Katy Sheen
• 金额: $ 324.42万
• 依托单位: UNIVERSITY OF EXETER
• 依托单位国家: 英国
• 项目类别: Fellowship
• 财政年份: 2024
• 资助国家: 英国
• 起止时间: 2024 至 无数据
• 项目状态: 未结题
• 来源: https://gtr.ukri.org/projects?ref=MR%2FX035611%2F1
• 关键词: Capturing; Oceanic; Submesoscales; Stirring; Mixing

The global oceans act as a sponge, soaking up significant amounts of the excess heat and carbon that have been added to the atmosphere due to human activity. Our oceans therefore play a key role in buffering the magnitude of climate change. However, the future storage capacity of the ocean sponge is uncertain, alongside the distribution of nutrients and oxygen, key ingredients for a healthy marine ecosystem. To address these uncertainties, we need to better understand how the oceans flow deep below the surface layers - in particular current flows that span scales of tens of metres to hundreds of kilometers, otherwise known as submesoscales. Submesoscale currents matter because they provide a pathway to harness energy from the winds and tides and use it to stir and mix different water masses around the globe, along with the heat, carbon and nutrients that they carry. Despite their importance, little is known about ocean submesoscales because of their intermediate size and intermittent nature. This means they are both difficult to capture in nature or model with computers. In this project, my team will conduct a pioneering experiment that will capture for the first time the full range of current flows that exist beneath the surface ocean layers, alongside the mixing and stirring that they generate. A targeted sea-going programme using active acoustics will sample the ocean at unprecedented resolutions (two orders of magnitude better than other techniques) and fully capture submesoscale currents. Similar to how bats echo-locate, a ship at the surface releases sound pulses into the water and records reflections from water layers. Acoustic measurements will be combined for the first time with cutting-edge robotics, vessel-mounted and moored instrumentation. In parallel, state-of-the-art model simulations will be both validated and improved using our new ocean observation data. The result will be the most realistic representation of the sub-surface ocean to date. The simulations will be used to quantify submesoscale initiation, ubiquity and interactions, and assess their role in driving energy and property exchanges in the global ocean. The experiment will take place at a global hotspot of ocean activity: the Brazil-Malvinas Confluence off the coast of Argentina. Here sub-tropical waters from the Atlantic collide with polar waters from the Southern Ocean. Water mass exchanges at this confluence, which are likely driven by submesoscale currents, play a key role in the distribution of heat, salt, carbon and life sustaining nutrients and oxygen throughout the global oceans. By revealing interior ocean dynamics in unparalleled detail at the Brazil-Malvinas Confluence, COSSMoSS will shed light on a significant missing piece of the scientific ocean puzzle helping us to better understand our future biosphere and climate.

全球海洋就像一块海绵，吸收了大量因人类活动而添加到大气中的多余热量和碳。因此，我们的海洋在缓冲气候变化方面发挥着关键作用。然而，海洋海绵未来的存储能力以及健康海洋生态系统的关键成分营养物和氧气的分布都不确定。为了解决这些不确定性，我们需要更好地了解海洋在表层以下深处如何流动，特别是跨越数十米到数百公里尺度（也称为亚中尺度）的洋流。次尺度水流很重要，因为它们提供了一种利用风和潮汐能量的途径，并用它来搅拌和混合全球不同的水团及其携带的热量、碳和营养物质。尽管海洋亚中尺度很重要，但由于其中等大小和间歇性，人们对它们知之甚少。这意味着它们都很难在自然界中捕获或用计算机建模。在这个项目中，我的团队将进行一项开创性的实验，该实验将首次捕获存在于表层海洋层之下的全方位水流，以及它们产生的混合和搅拌。使用主动声学的有针对性的海上计划将以前所未有的分辨率（比其他技术好两个数量级）对海洋进行采样，并完全捕获亚中尺度水流。与蝙蝠回声定位的方式类似，水面上的船只向水中释放声音脉冲并记录水层的反射。声学测量将首次与尖端机器人技术、船载和系泊仪器相结合。与此同时，最先进的模型模拟将利用我们新的海洋观测数据得到验证和改进。结果将是迄今为止最真实的地下海洋表现。这些模拟将用于量化亚中尺度的起始、普遍性和相互作用，并评估它们在推动全球海洋能源和财产交换中的作用。该实验将在全球海洋活动热点：阿根廷海岸附近的巴西-马尔维纳斯交汇处进行。在这里，来自大西洋的亚热带水域与来自南大洋的极地水域发生碰撞。这个汇合处的水团交换可能是由亚尺度水流驱动的，在整个全球海洋中热量、盐、碳以及维持生命的营养物质和氧气的分配中发挥着关键作用。通过以无与伦比的细节揭示巴西-马尔维纳斯交汇处的内部海洋动力学，COSSMoSS 将揭示科学海洋难题中一个重要的缺失部分，帮助我们更好地了解未来的生物圈和气候。