Understanding Climate-Biogeochemical Feedbacks During the Last Glacial Cycle: A Systematic Modeling and Paleo-Data Synthesis Approach

了解末次冰川周期期间的气候生物地球化学反馈：系统建模和古数据合成方法

• 批准号: 0712690
• 负责人: Axel Timmermann
• 金额: $ 31.41万
• 依托单位: University of Hawaii
• 依托单位国家: 美国
• 项目类别: Standard Grant
• 财政年份: 2007
• 资助国家: 美国
• 起止时间: 2007-07-01 至 2010-12-31
• 项目状态: 已结题
• 来源: https://www.nsf.gov/awardsearch/showAward?AWD_ID=0712690&HistoricalAwards=false
• 关键词: Understanding; Climate; Biogeochemical; Feedbacks; During

The researcher, and colleagues, will use a systematic modeling approach to disentangle the controlling forcing functions, as well as amplifying mechanisms, of millennial and glacial-interglacial climate variability. The general scientific goal of the research is an improved understanding of the dynamic role of physical and biogeochemical processes during the transition from the last glacial into the Holocene.Specifically, the researcher will use a global three-dimensional dynamical atmosphere-ocean-sea ice model of intermediate complexity coupled to a vegetation model and a marine carbon cycle model to develop transient simulations covering the last glacial termination and the entire Holocene period. The model simulation output will be directly compared, in terms of amplitude, timing and seasonality, with publicly available marine, as well as terrestrial, proxy archives involving data from sediment cores, ice cores, speleothems, and lake-level indices.The research strategy is designed to pursue the following scientific questions:How does the global carbon cycle respond to orbitally-driven climate variations? How important are orbitally-induced changes of the southern hemispheric westerlies in driving atmospheric carbon dioxide variations? What role does the carbon cycle response play in accelerating glacial-interglacial transitions?What role does the carbon cycle play in modulating millennial-scale climate variability during the last glacial period? The research will help to improve the wider science community''s understanding of the radiative sensitivity of Earth with possible implications for the understanding of future climate. The research strategy will specifically help differentiate, regionally, between various climate forcing factors and aid further efforts to interpret paleo-proxy data from the last glacial period. The research project will also enable the training of a postdoctoral scholar and a graduate student in paleoclimate modeling and data analyses.

该研究人员及其同事将使用系统的建模方法来解开千禧年和冰期-间冰期气候变率的控制强迫函数以及放大机制。研究的总体科学目标是提高对末次冰期到全新世过渡期间物理和生物地球化学过程的动态作用的认识。具体而言，研究人员将使用中等复杂程度的全球三维动态大气-海洋-海冰模型，结合植被模型和海洋碳循环模型，开发覆盖末次冰期终止和整个全新世的瞬态模拟。在幅度、时间和季节性方面，将直接将模式模拟输出与公开的海洋和陆地代理档案进行比较，这些档案涉及来自沉积物岩心、冰芯、洞穴主题和湖泊水平指数的数据。该研究策略旨在探讨以下科学问题：全球碳循环如何响应轨道驱动的气候变化？轨道引起的南半球西风带变化在驱动大气二氧化碳变化方面有多重要？碳循环响应在加速冰期-间冰期转变中起什么作用？在末次冰期，碳循环在调节千年尺度的气候变率中起什么作用？这项研究将有助于提高更广泛的科学界对地球辐射敏感性的理解，并可能对未来气候的理解产生影响。该研究策略将特别有助于区分不同区域的气候强迫因子，并有助于进一步解释末次冰期的古代用数据。该研究项目还将在古气候建模和数据分析方面培养一名博士后学者和一名研究生。