Collaborative Research: Investigating Climate System Sensitivity to Ice Age Orbital Forcing

地球轨道随时间的变化是低频气候变化的主要驱动因素之一。虽然地球轨道对日射的影响是已知的，但对轨道-气候关系的理解是不完整的。许多上新世-更新世古气候记录中的轨道特征与局地太阳辐射强迫并不一致。这项工作的目标是调查轨道强迫如何影响气候系统，并确定气候过程和反馈，调节这种强迫。为此，PI开发了一个地球系统模型，包括大气，海洋，冰盖和植被响应，并能够在多个轨道周期内运行长时间的瞬态模拟。除了一般调查轨道气候联系，PI还将使用他们的模型来解决上新世-更新世代理记录提出的悖论，包括（i）冰川41-kyr问题，（ii）热带41-kyr问题，（iii）气候对轨道强迫敏感性的演变，以及（iv）冰川100-kyr问题。该奖项将支持研究生和本科生的研究经验。一个关于冰河时代的博物馆展览将与密歇根大学合作开发？自然历史博物馆展览。

Changes in Earth's orbit through time are one of the main drivers of low frequency climate change. Though the influence of Earth's orbit on insolation is known, understanding of the orbit-climate link is incomplete. The orbital characteristics in many Plio-Pleistocene paleoclimate records are not consistent with local insolation forcing. The objective of this work is to investigate how orbital forcing affects the climate system, and to identify climate processes and feedbacks that modulate this forcing. To do this, the PIs have developed an earth system model that includes atmosphere, ocean, ice sheets, and vegetation responses, and is capable of running long transient simulations over multiple orbital cycles. In addition to generally investigating the orbit-climate link, the PIs will also use their model to address paradoxes raised by Plio-Pleistocene proxy records including (i) the glacial 41-kyr problem, (ii) the tropical 41-kyr problem, (iii) the evolution of climate sensitivity to orbital forcing, and (iv) the glacial 100-kyr problem. The award will support a graduate student and research experiences for undergraduates. A museum display on Ice Ages will be developed in collaboration with the University of Michigan?s Exhibit Museum of Natural History.