Southern Hemispheric Climate and Carbon Cycle Reponse to Orbital Forcing During the Last ~400,000 Years

该项目涉及使用中等复杂性的地球系统模型运行一系列瞬变气候模型模拟。目标是研究南半球轨道速度较快的更新世气候变化的潜在机制。具体地说，一个中等复杂性的全球大气-海洋-海冰模型，再加上一个植被模型和一个海洋碳循环模型，将用于一套涵盖过去四个冰川-间冰期周期的瞬变气候模拟。温室气体浓度的历史，轨道引起的太阳辐射变化，以及主要冰川冰盖时间演变的基于模型的重建将迫使该模型。研究人员将解决三个问题：i)温室气体变化和局部轨道强迫如何影响南半球的海冰范围、气候和海洋通风；ii)南半球西风对轨道尺度外部强迫的敏感性；iii)海洋碳循环如何响应轨道引起的海洋通风变化。主要的更广泛的影响包括更好地模拟气候和碳循环在很长一段时间内的变化，以及支持一名女性博士后学者。

This project involves running a series of transient climate model simulations with an earth system model of intermediate complexity. The goal is to examine the underlying mechanisms of orbitally-paced Pleistocene climate change in the Southern Hemisphere. Specifically, a global atmosphere-ocean-sea ice model of intermediate complexity, coupled to a vegetation model and a marine carbon cycle model, will be used in the suite of transient climate simulations covering the last four glacial-interglacial cycles. The model will be forced by the history of greenhouse gas concentrations, orbitally-induced changes of solar insolation, and model-based reconstructions of the time evolution of the major glacial ice-sheets.The researchers will address three issues: i) how greenhouse gas variations and local orbital forcing affect sea-ice extent, climate, and ocean ventilation in the Southern Hemisphere; ii) how sensitive Southern Hemispheric Westerlies are to orbital-scale external forcing; and iii) how the marine carbon cycle responds to orbitally-induced changes in ocean ventilation.The primary broader impacts involve better modeling of climate and carbon cycling variations over long time periods as well as supporting a female post doctoral scholar.