P2C2: P-E Land-C: Terrestrial Mediation of Carbon Cycle Response Through the Paleocene-Eocene Thermal Maximum

该奖项授予犹他州大学将支持现场，实验室和建模研究，以限制陆地生物地球化学变化在调节古新世-始新世热最大值（PETM）的环境和气候演变中的作用。PETM是碳循环引起的全球变化的地质事件，对地球的环境和生物系统产生了重大影响。虽然PETM变化的原因和性质的一般理解已经建立，一些异常的事件，包括其持续时间长，高明显的气候敏感性，和快速终止的特征，仍然无法解释。该项目将确定在古埃及新统期间是否发生了陆地临界带的变化，包括陆地植物和土壤中的碳储存、无机土壤碳酸盐的形成以及大陆沉积岩中有机碳和无机碳的埋藏，这些变化是否促成了在该事件期间观察到的全球变化模式。实地研究和实验室分析将记录美国西部和西班牙关键区域碳储量的变化，并重建伴随这些变化的当地环境条件。将开发和应用新的计算机模型组件，以评估所观察到的变化在全球范围内的重要程度，以及它们可能引起的全球气候和碳循环变化的模式，从而更全面地了解PETM事件。这些新的信息将被纳入针对研究生、本科生和高中生的教育材料中，这些材料将传达碳循环与地球系统变化在地质和人类时间尺度上的作用。大陆生态系统储存了大量的碳，这些碳很容易转移到大气中或从大气中吸收，影响全球气候。这些系统对全球变化的反应是未来环境条件预测中不确定性的主要来源，也是我们对过去气候地质记录的理解中的一个基本未知数。这项工作将测试关于碳储存如何随着全球气候变暖而变化的想法，这些想法是基于对现代生态系统的研究而开发的，通过对地质记录中记录最完整的快速气候变暖事件之一的重点研究。这些结果将提高我们对陆地碳循环反馈作为全球变化媒介的作用的理解，提高我们解释古气候记录和预测地球气候未来变化的能力。

This award to the University of Utah will support field, laboratory, and modeling studies to constrain the role of terrestrial biogeochemical change in modulating the environmental and climatic evolution of the Paleocene-Eocene thermal maximum (PETM). The PETM is a well-documented geological episode of carbon-cycle induced global change that had major repercussions on Earth's environmental and biotic systems. Although a general understanding of the causes and nature of PETM change has been established, a number of anomalous characteristics of the event, including its long duration, high apparent climate sensitivity, and rapid termination, remain unexplained. This project will determine whether changes in the terrestrial critical zone, including carbon storage in land plants and soils, formation of inorganic soil carbonate, and burial of organic and inorganic carbon in continental sedimentary rocks, occurred during the PETM and contributed to the pattern of global change observed during the event. Field studies and lab analyses will document critical zone carbon storage changes at sites in the western USA and Spain and reconstruct local environmental conditions that accompanied these changes. New computer model components will be developed and applied to evaluate the degree to which the observed changes were globally significant and the patterns of global climatic and carbon cycle change that they would have induced, thus providing a more comprehensive understanding of the PETM event. This new information will be incorporated in educational materials, targeted at the graduate, undergraduate, and high-school levels, that communicate the role of the carbon cycle coupled Earth system change over geological and human timescales.Continental ecosystems store a vast amount of carbon, which is potentially easily transferred to or taken up from the atmosphere, affecting global climate. The response of these systems to global change represents a major source of uncertainty in projections of future environmental conditions, as well as a fundamental unknown in our understanding of the geological record of past climate. This work will test ideas about how carbon storage changes as global climate warms, developed based on the study of modern ecosystems, through a focused study of one of the best-documented episodes of rapid climatic warming in the geologic record. The results will improve our understanding of the role of terrestrial carbon cycle feedback as a mediator of global change, advancing our ability to interpret the paleoclimate record and project future changes in Earth's climate.