The Variable and Changing Carbonate Chemistry of the Southern Ocean

南大洋是未来碳-气候系统预测的巨大不确定性和巨大潜在变化的来源。 在这个项目中，位于博尔德的科罗拉多大学的一个研究小组将开发改进的数值模型，以更好地预测未来几十年至几个世纪南大洋的碳吸收率。这将需要彻底了解南大洋可变和不断变化的碳酸盐化学，包括更好地限制目前的平均状态和季节周期，量化过去的变异性，并描述未来驱动变化的关键过程。该项目的主要数值工具将是社区地球系统模型，这是一个最先进的地球系统模型，具有充分互动的海洋生态系统和全球碳模块。 后报和21世纪世纪CESM模拟的输出、水文数据和卫星数据产品将用于理解模型偏差、解释变异性和量化碳气候反馈强度。具体目标是：（1）分析CESM中南大洋碱度循环的偏差，并指导其改进;（2）量化过去60年来模拟的南大洋碳酸盐化学的数十年变化，并利用卫星和水文数据集验证这些趋势;（3）确定南大洋碳酸盐化学年际至数十年变化的驱动因素;以及（4）量化南大洋由于酸化、层化和风驱动环流的变化而产生的碳反馈。通过量化南大洋无机碳酸盐化学过去的变化，并确定改变碳酸盐化学的物理和生态过程，该项目将为南大洋碳吸收和酸化的变化率提供新的见解。CESM的广大用户基础将受益于CESM中地球化学和生态学表述的拟议改进。更广泛的影响：这项研究将有助于更好地了解全球碳气候系统的未来演变，这对社会有直接的好处。这项工作的结果将通过在同行评审的期刊上发表和在科学会议上介绍而在科学界广泛传播。 它将支持一个早期的职业科学家和她的研究小组的发展。 PI是她所在机构夏季多元文化研究培训项目的导师，该项目旨在为属于在科学领域严重代表性不足的种族/民族的本科生提供研究实践经验和研究生教育介绍。、数学和工程。 该项目将支助两名研究生的教育和培训。该项目的重要研究成果将纳入科罗拉多大学的四门课程的课程。

The Southern Ocean is a source of great uncertainty and large potential change in predictions of the future carbon-climate system. In this project, a research team at the University of Colorado at Boulder will develop improved numerical models to better predict the rate of Southern Ocean carbon uptake over the next several decades to centuries. This will require a thorough understanding of the variable and changing carbonate chemistry of the Southern Ocean, including better constraints on the present-day mean state and seasonal cycle, quantification of past variability, and characterization of key processes driving change in the future. The primary numerical tool for this project will be the Community Earth System Model (CESM), a state-of-the-art Earth system model with fully interactive marine ecosystem and global carbon modules. Output from hindcast and 21st century CESM simulations, hydrographic data, and satellite data products will be used to understand model biases, interpret variability, and quantify carbon-climate feedback strength. The specific objectives are to: (1) analyze biases in, and guide improvement of, the Southern Ocean alkalinity cycle in the CESM; (2) quantify multi-decadal changes in modeled Southern Ocean carbonate chemistry over the last 60 years, and validate these trends with satellite and hydrographic data sets; (3) identify drivers of interannual to multi-decadal variability in Southern Ocean carbonate chemistry; and (4)quantify carbon feedbacks in the Southern Ocean due to changes in acidification, stratification, and wind-driven circulation. By quantifying past variability in the inorganic carbonate chemistry of the Southern Ocean, and identifying the physical and ecological processes that modify carbonate chemistry here, this project will offer new insights into the changing rate of Southern Ocean carbon uptake and acidification. The vast user base of the CESM stands to benefit from the proposed improvements in the representation of biogeochemistry and ecology in the CESM. Broader Impacts: This research will lead to a better understanding of the future evolution of the global carbon-climate system, which is of direct benefit to society. Results from this work will be widely disseminated in the scientific community through publication in peer-reviewed journals and presentation at scientific meetings. It will support an early-career scientist and the development of her research group. The PI is a mentor for the Summer Multicultural Access to Research Training program at her home institution, which aims to provide hands-on experience in research and an introduction to graduate education to undergraduate students who are members of racial/ethnic groups severely underrepresented in science, math, and engineering. The project will support the education and training of two graduate students. Significant research findings from this project will be incorporated into the curriculum of four courses at the University of Colorado.