Collaborative Research: Aerosols, Nitrogen Oxides, and Ozone at the Mt. Bachelor Observatory

该项目支持继续在Mt.学士天文台（MBO）在中央俄勒冈州。 MBO是一个高海拔（海拔2.8公里）观测站，过去15年来一直用于大气化学研究。 该项目将建立在MBO过去观测的广泛知识基础上，以研究美国西部春季空气质量的关键控制措施，春季是自然和国际人为来源的O3和气溶胶占主导地位，夏季是野火烟雾是区域空气污染的主要驱动因素。将在MBO对O3、CO、CO2、气溶胶质量、散射和吸收系数以及气象学进行连续测量。 本研究提出三个假设：（1）O3浓度的日变化受大尺度动力学和输送的驱动，包括厄尔尼诺-南方涛动、太平洋年代际涛动和气候变化。在MBO和克里思卫星的数据中可以观察到O3的变化，这对美国西部的顺风空气质量很重要。（2）生物质燃烧羽流中的氮氧化物化学受初始排放和途中化学处理的控制。 从气溶胶硝酸盐（有机和无机）产生亚硝酸是重要的NOx再循环机制和羟基自由基的来源。 (3)气溶胶的性质取决于化学成分和老化。棕碳的光吸收可以与黑碳相当或超过黑碳的吸收，并且可以与特定的化学成分或发色团相关联。有机气溶胶挥发性随着老化和氧化而降低。该奖项反映了NSF的法定使命，并通过使用基金会的知识价值和更广泛的影响审查标准进行评估，被认为值得支持。

This project supports the continuation of atmospheric measurements at Mt. Bachelor Observatory (MBO) in Central Oregon. The MBO is a high elevation (2.8 km above sea level) observatory that has been utilized for atmospheric chemistry research for the past 15 years. This project will build on the extensive knowledge base of past observations from MBO to examine key controls on western U.S. air quality in the spring, when natural and international anthropogenic sources of O3 and aerosols dominate, and summer, when wildfire smoke is a major driver of regional air pollution. Continuous measurements will be made at MBO of O3, CO, CO2, aerosol mass, scattering and absorption coefficients and meteorology. Three specific hypotheses will be addressed in this research: (1) Daily variations in baseline O3 are driven by large scale dynamics and transport including the El Nino-Southern Oscillation, the Pacific Decadal Oscillation, and the changing climate. The variations in O3 that can be observed in data from both MBO and the TEMPO satellite and are important for downwind air quality in the western U.S. (2) Nitrogen oxide chemistry in biomass burning plumes is controlled by both initial emissions and chemical processing enroute. Production of nitrous acid from aerosol nitrates (organic and inorganic) is an important NOx recycling mechanism and a source of hydroxyl radical. (3) Aerosol properties depend on chemical composition and aging. Light absorption by brown carbon can be comparable or exceed absorption by black carbon and can be linked to specific chemical components or chromophores. Organic aerosol volatility decreases with aging and oxidation.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.