Up in smoke! Terrestrial carbon cycle feedbacks during warm climates

沉积岩中的有机碳是一种重要的碳储集层，对大气CO2和O2的长期演化乃至全球气候都起着至关重要的作用。在隆升、挖掘和侵蚀过程中，化石OC的氧化有可能通过正气候反馈成为大气CO2的重要来源。然而，化石OC氧化在未来温暖气候中的重要性在我们的理解中仍然是一个主要的差距。测试地球在比现在更温暖的气候状态下的行为的一种方法是检查地质记录。古新世/始新世极热期（PETM）是近代地质史上最快速的变暖事件，是对未来气候变化的模拟。来自这段时间的诱人证据表明，化石OC氧化可能起到了积极的反馈作用。然而，这一点尚未在全球得到证实。该项目的目的是使用多代理方法来测试温暖气候是否与化石OC的增强侵蚀、动员和氧化有关，并确定这种机制是否可能作为大气CO2的主要来源。

Organic carbon preserved within sedimentary rocks (fossil OC) is a major carbon reservoir and plays a crucial role in the long-term evolution of atmospheric CO2 and O2, and thus global climate. The oxidation of fossil OC during uplift, exhumation and erosion has the potential to become an important source of CO2 to the atmosphere through positive climate feedbacks. However, the importance of fossil OC oxidation in future warm climates remains a major gap in our understanding.One way to test the behaviour of the Earth in warmer-than-present climate states is to examine the geological record. The Paleocene/Eocene Thermal Maximum (PETM) is the most rapid warming event in recent geologic history and is an analog for future climate change. Tantalizing evidence from this interval suggests that fossil OC oxidation may act as a positive feedback. However, this has yet to be globally confirmed. The aim of this project is to use a multi-proxy approach to test whether warm climates are associated with enhanced erosion, mobilization and oxidation of fossil OC and to determine whether this mechanism might act as a large source of atmospheric CO2.