Role of dust, climate, and marine biota in glacial-interglacial CO2 cycles

灰尘、气候和海洋生物群在冰期-间冰期二氧化碳循环中的作用

• 批准号: 342251-2007
• 负责人: Kohfeld, Karen
• 金额: $ 1.53万
• 依托单位: Simon Fraser University
• 依托单位国家: 加拿大
• 项目类别: Discovery Grants Program - Individual
• 财政年份: 2009
• 资助国家: 加拿大
• 起止时间: 2009-01-01 至 2010-12-31
• 项目状态: 已结题
• 来源: https://www.nserc-crsng.gc.ca/ase-oro/Details-Detailles_eng.asp?id=430065
• 关键词: Role; dust; climate; marine; biota

Antarctic ice-core records document dramatic changes in atmospheric CO2 over the past 8 glacial cycles (740,000 years). The goal of this research program is to obtain a better understanding of the processes controlling carbon sequestration in the ocean throughout the last full glacial-interglacial cycle by investigating the linkages between dust input, physical oceanography, and marine biology. The specific research objectives are: (1) to measure changes in surface water stratification (due to ice melt), dust inputs, and carbon export to the seafloor as archived in marine sediments over the last 140,000 years, specifically in the North Pacific Ocean; (2) to develop a global database of paleoceanographic proxies that record biogenic fluxes and ocean characteristics over the past 140,000 years, in order to examine the phasing of physical, chemical, and biological changes as the earth enters a glaciation; and (3) to use a biogeochemistry model in concert with these newly-developed environmental databases to assess the dominant controlling processes (iron flux or stratification) on marine productivity. Sediment analyses and collaborative modeling work will elucidate the different hydrographic and geochemical processes that have affected atmospheric CO2 while the earth was entering into and coming out of the last major glacial period, and how they are expected to affect carbon sequestration and atmospheric CO2 in the face of future climate change.

南极冰芯记录记录了过去8个冰期周期（74万年）大气中二氧化碳的剧烈变化。这项研究计划的目标是通过研究尘埃输入、物理海洋学和海洋生物学之间的联系，更好地了解在整个最后一个完整的冰期-间冰期循环中控制海洋碳封存的过程。具体的研究目标是：(1)测量过去14万年（特别是北太平洋）海洋沉积物中地表水分层（由于冰融化）、粉尘输入和向海底输出碳的变化；(2)建立一个记录过去14万年生物通量和海洋特征的全球古海洋学代用物数据库，以考察地球进入冰期时物理、化学和生物变化的分阶段；(3)利用生物地球化学模型结合这些新开发的环境数据库来评估海洋生产力的主要控制过程（铁通量或分层）。沉积物分析和协同建模工作将阐明地球进入和走出最后一个主要冰期时影响大气二氧化碳的不同水文和地球化学过程，以及面对未来气候变化，它们将如何影响碳固存和大气二氧化碳。