Collaborative Research: Verification of Atmospheric Mercury Redox Rates

合作研究：大气汞氧化还原率的验证

• 批准号: 2321379
• 负责人: Sarrah Dunham-Cheatham
• 金额: $ 23.54万
• 依托单位: Board of Regents, NSHE, obo University of Nevada, Reno
• 依托单位国家: 美国
• 项目类别: Standard Grant
• 财政年份: 2023
• 资助国家: 美国
• 起止时间: 2023-09-01 至 2026-08-31
• 项目状态: 未结题
• 来源: https://www.nsf.gov/awardsearch/showAward?AWD_ID=2321379&HistoricalAwards=false
• 关键词: Collaborative; Research; Verification; Atmospheric; Mercury

The cross-institutional collaborative investigators in this project will provide a new comprehensive dataset of compounds involved in the oxidation of mercury in the atmosphere by quantitatively measuring divalent mercury compounds, which are the more water-soluble forms of mercury. Mercury is emitted into the atmosphere in the elemental state, which undergoes various reactions with atmospheric oxidants into the divalent form, but there exist many uncertainties about which oxidant species and what rates these reactions occur. The primary objective of this project is to use these new measurements of speciated mercury, along with previous measurements, to quantitatively characterize both the speciation of mercury and the radical budget of sampled plumes in the Salt Lake City region nearby a magnesium mining facility (U.S. Magnesium). Two graduate students will be trained over the course of this project, and the project team plans on providing policy makers with updated information pertaining to mercury chemistry and the impacts on human health. The team also has plans to engage with state regulators to potentially extend the societal benefits of the knowledge gained.A recent discovery pertaining to standard measurement techniques has revealed a systematic low bias that affects nearly all previous measurements of divalent mercury. The dual-channel continuous mercury measurement system developed, tested, and previously deployed by this research group can make divalent mercury measurements without this low bias. The work has three specific aims: (1) to conduct a year-long measurement campaign of elemental and divalent mercury, related oxidants, and other chemical and meteorological variables; (2) use the zero-dimensional F0AM model to identify which mercury chemical mechanisms and reaction rates minimize model-measurement discrepancies; and (3) update GEOS-Chem’s mercury oxidation mechanism with the F0AM parameters to minimize GEOS-Chem model-measurement discrepancies. Results from this work will enhance our understanding of mercury chemistry and chemical species affected by mercury chemistry, including halogens, ozone, and nitrogen oxides.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.

该项目中的跨机构合作调查人员将通过定量测量二价汞化合物，这是大气中汞氧化涉及的化合物的新综合数据集，这是汞含水更大的汞形式。汞发射到元素状态的大气中，该元素与大气中的氧化剂发生了各种反应，但存在许多不确定性的氧化物物种以及这些反应发生的速率。该项目的主要目的是使用这些新的指定汞的测量结果以及先前的测量值，以定量地表征汞的规格和盐湖城地区镁采矿设施（美国镁）附近的盐湖城地区采样李子的根本预算。将在该项目的整个过程中对两名研究生进行培训，项目团队计划为决策者提供与汞化学有关的最新信息以及对人类健康的影响。该团队还计划与州监管机构互动，以扩大与标准测量技术有关的最新发现的社会益处。显示了系统的低偏见，几乎影响了先前所有的二价汞测量结果。该研究小组开发，测试和以前部署的双通道连续汞测量系统可以进行二价汞测量值，而不会出现这种低偏差。这项工作具有三个特定的目的：（1）进行长达一年的元素和二价汞，相关氧化物以及其他化学和气象变量的测量； （2）使用零维f0am模型来确定哪些汞化学机制和反应速率最小化模型测量差异； （3）使用F0AM参数更新Geos-Chem的汞氧化机制，以最大程度地减少GEOS-CHEM模型测量差异。这项工作的结果将增强我们对受汞化学影响的汞化学和化学物种的理解，包括卤素，臭氧和氮氧化物。该奖项反映了NSF的法定任务，并被认为是通过基金会的智力优点和更广泛的影响综述标准来通过评估来评估的。