Can you hear marine snow falling?

你能听到海上降雪的声音吗？

• 批准号: NE/X009483/1
• 负责人: Katy Sheen
• 金额: $ 8.82万
• 依托单位: UNIVERSITY OF EXETER
• 依托单位国家: 英国
• 项目类别: Research Grant
• 财政年份: 2022
• 资助国家: 英国
• 起止时间: 2022 至 无数据
• 项目状态: 未结题
• 来源: https://gtr.ukri.org/projects?ref=NE%2FX009483%2F1
• 关键词: hear; marine; snow; falling

The global ocean plays a key role in our climate system by extracting and storing much of the carbon released by humans into the atmosphere, thereby buffering the effects of global warming. However, there are uncertainties as to how this important ocean-carbon sink may change in future, and critically a better understanding of the ocean-carbon system is needed to accurately predict the Earth's climate. A key driver of ocean carbon uptake is marine life: plants that live in the surface ocean convert the atmospheric carbon that is absorbed into the ocean into their body organic matter through photosynthesis. This organic matter eventually sinks to the deep ocean in the form of 'marine snow' where it can be locked up for thousands of years in seafloor sediments. Oceanographers typically use sediment-traps to capture and measure marine snow, however sediment traps can only collect data in one place on typically monthly timescales. The result is a severe lack of information about the shorter time and space scale variability of marine snow, making it difficult to understand the processes that mediate ocean carbon storage. In this project we will develop a novel method to repurpose standard oceanographic acoustic current meter data, typically collected alongside sediment traps, to estimate carbon fluxes at much higher temporal resolutions (hours). We will use backscatter data, also recorded by the acoustic current meter but normally disregarded as a bi-product. To test the method, we will analyse an exemplar data set collected in the Southern Ocean which consists of both sediment-trap and acoustic backscatter data. As well as providing carbon flux data at yet unresolved temporal scales, output from this project can be applied to a wealth of legacy acoustic data (e.g. current data records collected across the world oceans over past decades), greatly improving the global coverage of past and present carbon flux estimates. Ultimately, we will improve the ability to understand and predict the future carbon storage capacity of the ocean and hence the Earth's climate.

全球海洋在我们的气候系统中起着关键作用，通过提取和存储人类释放的大部分碳进入大气中，从而缓冲全球变暖的影响。但是，对于这种重要的海洋碳汇率如何在未来可能发生变化存在不确定性，并且需要对海洋碳体系有更好的了解来准确地预测地球的气候。海洋碳吸收的主要驱动力是海洋生物：生活在水中的植物通过光合作用将被吸收到海洋中的大气碳转化为身体有机物。这种有机物最终以“海洋雪”的形式沉入深海，在海底沉积物中可以锁定数千年。海洋学家通常使用沉积物陷阱来捕获和测量海洋雪，但是沉积物陷阱只能在通常每月的时间表上的一个地方收集数据。结果是严重缺乏有关海洋积雪时间和空间尺度变化较短的信息，这使得很难理解介导海洋碳储存的过程。在这个项目中，我们将开发一种新型方法，以重新利用标准的海洋学电流电流仪表数据，通常与沉积物陷阱一起收集，以估算更高的时间分辨率（小时）的碳通量。我们将使用反向散射数据，该数据也由声流仪表录制，但通常被视为双层产品。为了测试该方法，我们将分析在南海中收集的示例数据集，该数据集由沉积物陷阱和声学反向散射数据组成。除了在尚未解决的时间尺度上提供碳通量数据外，该项目的输出还可以应用于大量的传统声学数据（例如，过去几十年来全球海洋收集的当前数据记录），大大改善了过去和现在的碳通量估算的全球报道。最终，我们将提高理解和预测海洋未来碳存储能力，从而提高地球气候的能力。