Collaborative Research: Earth-Life Transitions: Integrated Data-Model Analysis of CO2-Climate-Vegetation Feedbacks in a Dynamic Paleo-Icehouse

合作研究：地球-生命转变：动态古冰库中二氧化碳-气候-植被反馈的综合数据模型分析

• 批准号: 1338200
• 负责人: Christopher Poulsen
• 金额: $ 33万
• 依托单位: Regents of the University of Michigan - Ann Arbor
• 依托单位国家: 美国
• 项目类别: Continuing Grant
• 财政年份: 2014
• 资助国家: 美国
• 起止时间: 2014-01-01 至 2021-12-31
• 项目状态: 已结题
• 来源: https://www.nsf.gov/awardsearch/showAward?AWD_ID=1338200&HistoricalAwards=false
• 关键词: Collaborative; Research; Earth; Life; Transitions

COLLABORATIVE RESEARCH :Integrated Data-Model Analysis of CO2-Climate-Vegetation Feedbacks in a Dynamic Paleo-IcehousebyIsabel Montanez, Univ. California, Davis EAR-1338281Christopher Poulsen, Univ. Michigan, EAR-1338200Joseph White, Baylor University, EAR-1338247Michael Hren, Univ. Conneticutt, EAR-1338256ABSTRACTOverview: Vegetation-CO¬2-climate feedbacks have been shown to be an important component of the climate system, capable of perturbing atmospheric circulation, continental surface temperatures, and hydrological cycling on regional- to global-scales. Recent work indicates that vegetation-climate feedbacks likely had the potential to push the late Paleozoic climate system between glacial and interglacial states and to strongly modify the climate regime within these states. The details of the nature, time-scales, and potential impact of these feedbacks remain elusive. This multi-disciplinary project, driven by three interlinked hypotheses, addresses these shortcomings and analyzes the roles of CO2- and orbital-forcing and vegetation-climate feedbacks in promoting glacial-interglacial transitions on eccentricity- to multi-million year time-scales: - The response of vegetation to primarily CO2-driven glacial-interglacial transitions depended on the timing, magnitude and duration of CO2 forcing and whether critical ecological thresholds were reached.- Tropical vegetation, by way of physiological forcing, impacted low-latitude climate and water & C cycling- Vegetation-climate feedbacks - on a global-scale - amplified radiatively forced glacial-interglacial transitions through changes in direct surface forcing and terrestrial C & N cycling.These hypotheses are being tested through integrated empirical, experimental and multi-scale modeling approaches across a spectrum of time- (10 to 1,000,000 yr) and spatial-scales (leaf-to-canopy-to-global climate system). Climate-CO2-vegetation feedbacks, including the role of plant physiological forcing of climate will be assessed through a two-stage modeling effort that will first reformulate a terrestrial biosphere model (BIOME-BGC) using the empirical and experimental results coupled with modeling sensitivity experiments to define plant functional traits for late Paleozoic PFTs. In the second stage, we will incorporate these PFT traits into NCAR's fully coupled Community Earth System Model and use this version to investigate glacial-interglacial dynamics.Intellectual Merit: This research will generate the first high-resolution, high-precision reconstruction of atmospheric CO2 during the LPIA, which when incorporated into the climate modeling will provide insight into the evolution of earth system processes, including the terrestrial biosphere, in an icehouse under changing CO2 levels relevant to our long-term future. This study will be the first modification of terrestrial biosphere models to account for paleo-PFT traits and investigation of paleovegetation-climate feedbacks thus providing an improved understanding of the potential of non-angiosperm plants to influence hydrologic and C cycling through physiological forcing. Broader Impacts: Cross-disciplinary training and mentoring will occur through in-residence internships for the Ph.D. students. Underrepresented students to Earth and environmental sciences will be integrated through a range of summer and academic year internships and programs at the collaborating institutions. This study will contribute directly to a Carboniferous exhibit planned for the Paleontological Halls of the National Museum of Natural History, Smithsonian Institution. All data generated by this study will be archived and shared via publications, and web-accessible tools.

合作研究：动态古冰库中二氧化碳气候植被反馈的综合数据模型分析作者：Isabel Montanez，加州大学，戴维斯 EAR-1338281Christopher Poulsen，密歇根大学，EAR-1338200约瑟夫·怀特，贝勒大学，EAR-1338247Michael Hren，康涅狄格大学，EAR-1338256摘要概述：植被-CO-2-气候反馈已被证明是气候系统的重要组成部分，能够扰动区域到全球范围内的大气环流、大陆表面温度和水文循环。最近的研究表明，植被-气候反馈可能有可能推动晚古生代气候系统在冰期和间冰期之间的变化，并强烈改变气候这些反馈的性质、时间尺度和潜在影响的细节仍然难以捉摸，这个由三个相互关联的假设驱动的多学科项目解决了这些缺点并嵌套了二氧化碳和轨道强迫的作用。植被-气候反馈在偏心率至数百万年时间尺度上促进冰川-间冰期转变： - 植被对主要由二氧化碳驱动的冰川-间冰期转变的响应取决于二氧化碳强迫的时间、幅度和持续时间以及是否达到关键生态阈值。 - 热带植被通过生理强迫影响低纬度气候以及水和碳循环 - 植被-气候反馈 - 在全球范围内 - 辐射放大通过直接地表强迫和陆地碳氮循环的变化来强制冰川-间冰期转变。这些假设正在通过跨时间范围的综合经验、实验和多尺度建模方法进行测试-（10到 1,000,000 年）和空间尺度（叶子到冠层到全球气候系统），包括气候植物生理强迫的作用将通过两阶段建模工作进行评估。首先使用经验和实验结果结合建模敏感性实验重新制定陆地生物圈模型（BIOME-BGC），以定义晚古生代 PFT 的植物功能特征。在这一阶段，我们将把这些 PFT 特征纳入 NCAR 的完全耦合社区地球系统模型中，并使用该版本来研究冰河-间冰河动力学。 智力价值：这项研究将在 LPIA 期间首次对大气二氧化碳进行高分辨率、高精度重建，当纳入气候模型时，将深入了解与我们的长期未来相关的二氧化碳水平变化下的地球系统过程（包括陆地生物圈）的演变。首次修改陆地生物圈模型以考虑古 PFT 特征并调查古植被气候反馈，从而更好地了解非被子植物通过生理强迫影响水文和碳循环的潜力：跨学科培训。地球和环境科学领域的博士生将通过一系列暑期和学年实习和项目进行住院实习。这项研究将直接为史密森学会国家自然历史博物馆古生物学馆计划的石炭纪展览做出贡献。这项研究产生的所有数据都将通过出版物和网络访问工具进行存档和共享。