Assessing the Ability of Measurements of Carbon-14 of Atmospheric Carbon Monoxide in a Global Network to Improve Understanding of Spatial and Temporal Hydroxyl Radical Variability

评估全球网络中大气一氧化碳碳 14 的测量能力，以提高对时空羟基自由基变化的理解

• 批准号: 1920602
• 负责人: Vasilii Petrenko
• 金额: $ 82.42万
• 依托单位: University of Rochester
• 依托单位国家: 美国
• 项目类别: Standard Grant
• 财政年份: 2019
• 资助国家: 美国
• 起止时间: 2019-08-15 至 2024-07-31
• 项目状态: 已结题
• 来源: https://www.nsf.gov/awardsearch/showAward?AWD_ID=1920602&HistoricalAwards=false
• 关键词: Assessing; Ability; Measurements; Carbon; 14

This project will develop and apply the capability for using global observations of the carbon-14 isotope of carbon monoxide (14CO) to assess the global distribution of the hydroxyl radical (OH) in the atmosphere. For the past ~20 years, methyl chloroform (MCF) observations have been effective at establishing the OH distribution, but the atmospheric abundance of MCF has now declined to the point where it is becoming less useful. The OH radical is the main atmospheric oxidant and determines the lifetimes of numerous radiatively important gases and regulated pollutants. Knowledge about the abundance and variability of the global distribution of OH is critical for accurately modeling air quality and climate change.The first phase of this project includes enhancing global observations by measuring 14CO once every 2 weeks for 1 full year at Barrow, Alaska; Mace Head, Ireland; Mauna Loa, Hawaii; Ragged Point, Barbados; American Samoa; La R'union Island, France; Baring Head, New Zealand and less frequently at Arrival Heights, Antarctica. As part of a pilot effort, the principal investigators of this project have developed a new method for 14CO observation that reduces the sample size requirement by an order of magnitude, allowing for simpler and less expensive logistics without sacrificing measurement quality. The new 14CO results will provide a globally-representative 14CO distribution over the course of a full year that can then be used to study the spatial and seasonal variability in OH concentrations, with the aid of the GEOS-Chem chemistry-transport model. MCF capability will also be developed in GEOS-Chem, and OH results from 14CO will be compared with OH inferred via MCF. Simulations of both MCF and 14CO will be performed together using GEOS-Chem, combining MCF's power to constrain global mean OH with 14CO's ability to infer OH spatial structure and seasonal changes. Changes in OH concentrations in space and time impact both global air quality and the rate of climate change. An improved understanding of tropospheric OH distribution and variability has significant broad interest within the atmospheric science research community.This award reflects NSF's statutory mission and has been deemed worthy of support through evaluation using the Foundation's intellectual merit and broader impacts review criteria.

该项目将开发和应用利用一氧化碳(14CO)碳14同位素的全球观测来评估大气中羟基自由基(OH)的全球分布的能力。在过去的20年里，甲基氯仿(MCF)的观测在建立OH分布方面是有效的，但现在大气中MCF的丰度已经下降到了不再有用的地步。OH自由基是主要的大气氧化剂，它决定了许多具有辐射重要性的气体和受管制污染物的寿命。该项目的第一阶段包括加强全球观测，在阿拉斯加的巴罗、爱尔兰的梅斯黑德、夏威夷的莫纳罗亚、巴巴多斯的拉格角、美属萨摩亚、法国的留尼汪岛、新西兰的巴林海德和南极洲的到达高地的观测频率较低。作为试点工作的一部分，该项目的主要研究人员开发了一种14CO观测的新方法，该方法将样本量要求减少了一个数量级，允许在不牺牲测量质量的情况下实现更简单和更便宜的后勤。新的14CO结果将提供具有全球代表性的全年14CO分布，然后可在GEOS-Chem化学输送模型的帮助下，用于研究OH浓度的空间和季节变化。还将在GEOS-Chem中开发MCF能力，并将从14CO得到的OH结果与通过MCF推断的OH进行比较。MCF和14CO的模拟将使用GEOS-Chem一起进行，将MCF约束全球平均OH的能力与14CO推断OH空间结构和季节变化的能力结合在一起。OH浓度在空间和时间上的变化既影响全球空气质量，也影响气候变化速度。更好地理解对流层OH的分布和变化在大气科学研究界具有重要的广泛意义。这一奖项反映了NSF的法定使命，并通过使用基金会的智力优势和更广泛的影响审查标准进行评估，被认为值得支持。

项目成果

An improved method for atmospheric ¹⁴CO measurements

大气 ¹⁴CO 测量的改进方法

• DOI: 10.5194/amt-14-2055-2021
• 发表时间: 2021
• 期刊: Atmospheric Measurement Techniques
• 影响因子: 3.8
• 作者: Petrenko, Vasilii V.;Smith, Andrew M.;Crosier, Edward M.;Kazemi, Roxana;Place, Philip;Colton, Aidan;Yang, Bin;Hua, Quan;Murray, Lee T.
• 通讯作者: Murray, Lee T.