Collaborative Research: P2C2--Exploring the Early Anthropogenic Hypothesis

合作研究：P2C2——探索早期人为假说

• 批准号: 0902802
• 负责人: Stephen Vavrus
• 金额: $ 39.35万
• 依托单位: University of Wisconsin-Madison
• 依托单位国家: 美国
• 项目类别: Standard Grant
• 财政年份: 2009
• 资助国家: 美国
• 起止时间: 2009-06-01 至 2013-05-31
• 项目状态: 已结题
• 来源: https://www.nsf.gov/awardsearch/showAward?AWD_ID=0902802&HistoricalAwards=false
• 关键词: Collaborative; Research; P2C2; Exploring; Early

Funding is provided to further test the early anthropogenic hypothesis (EAH) that agriculture produced greenhouse-gas emissions large enough to reverse natural downward trends in carbon dioxide and methane concentrations several thousand years ago by driving atmospheric levels of both gases upward and keeping the climate anomalously warm.Specifically, the researchers plan to: (1) re-examine a model parameterization that artificially limit snow thickness, in order to determine how this constraint affects the extent of permanent snow cover; (2) run model simulations with modern insolation but varying carbon dioxide and methane levels to determine the threshold for present-day glacial inception; (3) assemble data on modern and little ice age mountain glaciers and ice caps for comparison to the model simulations; (4) assemble archeological data on the spread of rice irrigation and livestock tending across southern Asia; and (5) conduct experiments with the NCAR CCSM4 model that include: (a) a 'no anthro' experiment using interactive vegetation with carbon dioxide physiology and a dynamical ocean to assess the full climatic impact of early agricultural greenhouse gases; (b) an experiment simulating late pre-industrial times in order to parcel out the climatic effects of early-agricultural versus industrial-era anthropogenic gases; and (c) an experiment using only direct carbon dioxide and methane inputs from humans to determine whether carbon dioxide feedbacks from the ocean can account for the full carbon budget needed to support a 35-40 parts per million atmospheric carbon dioxide anomaly.This research is potentially transformative because it provides a new perspective on climate forcing and challenges the broader science community's understanding of the extent of human impacts on climate.This award is funded under the American Recovery and Reinvestment Act of 2009 (Public Law 111-5).

提供资金以进一步测试早期人为假说（EAH），即农业产生的温室气体排放量足以扭转几千年前二氧化碳和甲烷浓度的自然下降趋势，通过推动大气中两种气体的浓度上升并保持气候异常具体来说，研究人员计划：（1）重新检查人为限制积雪厚度的模型参数化，以确定这种约束如何影响永久积雪的范围； (2) 使用现代日照但改变二氧化碳和甲烷水平进行模型模拟，以确定当今冰川起始的阈值； (3) 收集现代和小冰期山区冰川和冰盖的数据，以便与模型模拟进行比较； (4) 收集有关水稻灌溉和牲畜饲养在整个南亚地区传播的考古数据； (5) 使用 NCAR CCSM4 模型进行实验，其中包括： (a) 使用具有二氧化碳生理学和动态海洋的互动植被和动态海洋的“无人类”实验，以评估早期农业温室气体对气候的全面影响； (b) 模拟前工业时代晚期的实验，以区分早期农业与工业时代人为气体对气候的影响； (c) 一项仅使用人类直接输入的二氧化碳和甲烷的实验，以确定来自海洋的二氧化碳反馈是否可以解释支持百万分之 35-40 的大气二氧化碳异常所需的全部碳预算。这项研究是具有潜在的变革性，因为它提供了关于气候强迫的新视角，并挑战了更广泛的科学界对人类对气候影响程度的理解。该奖项由 2009 年美国复苏和再投资法案（公法）资助111-5）。