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

南极冰芯记录记录了过去8个冰川周期(740,000年)大气二氧化碳的戏剧性变化。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，更好地了解在上一个完整的冰川-间冰期周期中控制海洋中碳固定的过程。其具体研究目标是：(1)测量过去140,000年来海洋沉积物中存档的表层水分层(由于冰融化)、灰尘输入和向海底输出碳的变化，特别是在北太平洋；(2)建立一个全球古海洋学替代数据库，记录过去140 000年来的生物通量和海洋特征，以便研究地球进入冰川时物理、化学和生物变化的阶段性变化；(3)利用生物地球化学模型与这些新开发的环境数据库相结合，评估对海洋生产力的主要控制过程(铁通量或分层)。沉积物分析和协作建模工作将阐明在地球进入和离开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，以及它们在面对未来气候变化时预计将如何影响碳封存和大气二氧化碳。

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.