North Atlantic circulation during past abrupt climate events in the Holocene

北大西洋深水的形成和循环是全球气候系统的重要组成部分。在全新世(最后的11700年)，气候突变时期频繁发生，但北大西洋在这些事件之前的成因机制和作用尚不清楚。该项目的目的是确定在整个全新世关键的突然气候事件(例如，8.2ka、4.2ka和2.7ka BP事件)之前、期间和之后，深水的循环和形成发生了什么变化(如果有的话)。该项目将利用广泛的古海洋学指标，包括稳定同位素和痕量金属、可分类泥沙、放射性碳通风年龄和钕同位素组成的分析。这些方法将能够重建深水通风、流速和深水团的垂直分布。目前的模型很难重建过去的气候变化，北大西洋环流的稳定性在某种程度上仍然不确定。限制北大西洋在气候突变期间的行为对于限制气候突变所涉及的机制、改进对此类事件的气候模型模拟以及让我们了解未来发生类似突发事件的可能性至关重要。

The formation and circulation of deep waters in the North Atlantic is a critical component of the global climate system. Periods of abrupt climate change have occurred frequently during the Holocene (the last ~11,700 years), but the causal mechanisms and role of the North Atlantic preceding these events are not well understood. The aim of this project is to identify what changes, if any, occurred in the circulation and formation of deep waters before, during, and after key abrupt climate events throughout the Holocene (e.g., the 8.2ka, 4.2ka, and 2.7ka BP events). The project will utilise a wide range of palaeoceanographic proxies including analysis of stable isotopes and trace metals, sortable silt, radiocarbon ventilation age, and neodymium isotopic composition. These methods will enable the reconstruction of deep-water ventilation, flow speed, and the vertical distribution of deep watermasses. Current models struggle to reconstruct past climate variability, and the stability of the North Atlantic circulation remains somewhat uncertain. Constraining the behaviour of the North Atlantic during periods of abrupt climate is critical for constraining the mechanisms involved in abrupt climate change, improving climate model simulation of such events, and informing our understanding of the likelihood of similar abrupt events occurring in the future.