Investigating North Atlantic Circulation During the Last Deglaciation.

调查末次冰消期期间的北大西洋环流。

• 批准号: 2843423
• 金额: --
• 依托单位: University College London
• 依托单位国家: 英国
• 项目类别: Studentship
• 财政年份: 2023
• 资助国家: 英国
• 起止时间: 2023 至 无数据
• 项目状态: 未结题
• 来源: https://gtr.ukri.org/projects?ref=studentship-2843423
• 关键词: Investigating; North; Atlantic; Circulation; During

As a component of the global ocean conveyor belt of heat, salt and nutrients, the Atlantic Meridional Overturning Circulation (AMOC) plays a major part in the global climate system. Sensitive to warming ocean temperatures and freshwater input from melting ice sheets and sea-ice and increased high-latitude precipitation, the stability of AMOC may be at risk in a warming world. Variations in AMOC have been linked with abrupt shifts between warm (interstadial) and cold (stadial) conditions in proxy records of the last 150,000 years, but the extent of any AMOC weakening and the associated mechanisms are not fully constrained. This project seeks to investigate changes in North Atlantic hydrography throughout the events observed in records of the last deglaciation (~19-11 ka: between the Last Glacial Maximum and the Holocene). This project will use a range of palaeoceanographic proxies including sortable silt, and oxygen isotope, clumped isotope and trace metal analyses in marine carbonates to reconstruct deep ocean flow speed and temperature at three depth-transects in the Northwest Atlantic. The generation of these Northwest Atlantic records will fill a gap in basin-wide proxy data coverage, thus facilitating an investigation in the relative phasing and regional differences in hydrography throughout the last deglaciation. Ultimately, this will increase our understanding of the mechanisms behind abrupt climate changes and provide a test-case scenario with which to evaluate climate model performance.

大西洋经向翻转环流（AMOC）作为全球海洋热、盐和营养物输送带的组成部分，在全球气候系统中发挥着重要作用。 AMOC 对海洋温度变暖、冰盖和海冰融化带来的淡水输入以及高纬度降水增加敏感，在变暖的世界中，AMOC 的稳定性可能面临风险。 AMOC 的变化与过去 15 万年代理记录中温暖（场间）和寒冷（场间）条件之间的突然转变有关，但任何 AMOC 减弱的程度和相关机制并未完全受到限制。该项目旨在调查末次冰消期记录中观察到的北大西洋水文学的变化（~19-11ka：末次盛冰期和全新世之间）。该项目将使用一系列古海洋学代理，包括可分类淤泥、海洋碳酸盐中的氧同位素、团块同位素和痕量金属分析，以重建西北大西洋三个深度横断面的深海流速和温度。这些西北大西洋记录的生成将填补全流域代理数据覆盖范围的空白，从而促进对上次冰消期间水文学的相对阶段和区域差异的调查。最终，这将增加我们对气候突变背后机制的理解，并提供评估气候模型性能的测试案例场景。