The Chemistry and Sources of Carbon Monoxide in Present and Past Atmospheres

现在和过去大气中一氧化碳的化学性质和来源

• 批准号: 1136302
• 负责人: John Mak
• 金额: $ 62.83万
• 依托单位: SUNY at Stony Brook
• 依托单位国家: 美国
• 项目类别: Standard Grant
• 财政年份: 2011
• 资助国家: 美国
• 起止时间: 2011-10-01 至 2015-09-30
• 项目状态: 已结题
• 来源: https://www.nsf.gov/awardsearch/showAward?AWD_ID=1136302&HistoricalAwards=false
• 关键词: Chemistry; Sources; Carbon; Monoxide; Present

This research effort will (1) quantify temporal variability in contributions of major sources of CO over the past several thousand years and (2) begin to investigate the corresponding trends in OH. The work is motivated by the need to better understand the background chemistry of the CH4-OH-CO system in today's atmosphere relative to the range in variability over the past. OH largely determines both the chemical oxidation mechanisms and the lifetimes of most reactive atmospheric species. Similarly, CO is one of the most important reactive trace gases in the atmosphere because of its combined reactivity and abundance. Because of the close link between CO and CH4, these studies will also help to resolve mechanisms that drove CH4 concentration changes in the past. CO concentration, 13CO, and C18O will be measured in air trapped in archived core samples of firn and ice. Delt17O in CO will be measured as a proxy of large-scale OH abundance and temporal variability. The application of delt17O to constrain atmospheric OH has been demonstrated but a new analytical approach with the capability to characterize low-volume air bubbles in ice cores is required to extend the record to the past. The Principal Investigator (PI) will construct a new analytical system to measure delt17O in CO in low-volume air bubbled based on the system currently used to measure 13C and 18O in CO from ice cores and an offline system designed to measure of delt17O in CO from larger whole air samples.Quantifying OH variability is critical to understanding the overall fast photochemistry of the troposphere (NOx, CO, CH4, VOCs, SOx, secondary aerosols, etc.) and the lifetimes of H-containing greenhouse gases. One postdoctoral scientist and one graduate student will participate in and be trained through this project. In addition, two undergraduate geology majors at Stony Brook who plan to become high school teachers will be mentored by a local high school teacher. These undergraduate students will also mentor high school students in appropriate research topics through the PI's group. This pilot program will be evaluated by all students and teachers/advisors involved and, if successful, a broader program will be implemented.

这项研究工作将 (1) 量化过去几千年主要二氧化碳来源贡献的时间变化，以及 (2) 开始调查 OH 的相应趋势。 这项工作的动机是需要更好地了解当今大气中 CH4-OH-CO 系统相对于过去变化范围的背景化学。 OH 在很大程度上决定了化学氧化机制和大多数活性大气物质的寿命。同样，CO 因其综合反应性和丰度而成为大气中最重要的反应性微量气体之一。由于 CO 和 CH4 之间的密切联系，这些研究还将有助于解决过去驱动 CH4 浓度变化的机制。 CO 浓度、13CO 和 C18O 将在存档的冷杉和冰芯样本中捕获的空气中进行测量。 CO 中的 Delt17O 将作为大规模 OH 丰度和时间变化的代表进行测量。 delt17O 限制大气 OH 的应用已得到证实，但需要一种能够表征冰芯中低体积气泡的新分析方法，才能将记录延续到过去。 首席研究员 (PI) 将在目前用于测量冰芯中 CO 中 13C 和 18O 的系统以及旨在测量 CO 中 delt17O 的离线系统的基础上，构建一个新的分析系统，用于测量小体积气泡中 CO 中的 delt17O量化 OH 变化对于了解对流层整体快速光化学（NOx、CO、CH4、VOC、SOx、二次气溶胶、等）和含氢温室气体的寿命。一名博士后科学家和一名研究生将参与该项目并接受培训。 此外，石溪分校地质学专业的两名本科生计划成为高中教师，将得到当地高中教师的指导。 这些本科生还将通过 PI 小组指导高中生进行适当的研究课题。该试点计划将由所有参与的学生和教师/顾问进行评估，如果成功，将实施更广泛的计划。