Collaborative Research: Ammonia Phase PARtitioning and Transport (APART)

氨（NH3）的大气排放有助于形成影响人类和生态健康的细颗粒物和氮沉降，但对NH3的转化和归宿知之甚少。在这个项目中，研究小组打算在落基山国家公园（RMNP）的山脚下对主要牛和奶牛饲养场排放的NH3进行空中和地面测量。结果将有助于通知大气化学家和测试一个预测工具，减少氮顺风运输到一个敏感的生态系统。在2个机构和4个PI之间的合作项目中，计划在RMNP山麓进行为期10周的实地活动，以确定（i）大型源下风向10 km内NH3的通量和沉积时间尺度，以及（ii）相同源下风向~100 km NHx的空间分布和分区。主要的采样平台是怀俄明州大学空中国王（UWKA）研究飞机配备了新的测量能力，允许增强气体和颗粒物的采样策略。气态物质包括还原氮和氧化氮（NH3和HNO 3）、甲烷（CH 4）、乙烷（C2 H6）、一氧化碳（CO）、二氧化碳（CO2）和水蒸气（H2O），而颗粒物包括气溶胶浓度和尺寸以及它们的水溶性物质浓度。CH 4和C2 H6可以跟踪羽流并区分不同的源类型。将飞行数据与从移动的监测站和现有采样站收集的地面观测数据结合起来，可为今后更好地解释一贯提供的地面数据提供一种手段。研究结果还将有助于改善NH3在运输模型中的代表性，帮助预测当地的空气质量，并为利益相关者提供信息。两个研究生和几个本科生将获得宝贵的实践经验，在一个合作的现场活动。这个奖项反映了NSF的法定使命，并已被认为是值得通过评估使用基金会的智力价值和更广泛的影响审查标准的支持。

Atmospheric emissions of ammonia (NH3) contribute to the formation of fine particles and nitrogen deposition that affect human and ecological health, yet little is known about NH3 transformation and fate. In this project, the research team intends to perform airborne and ground-based measurements of NH3 emitted from major cattle and dairy feedlots in the foothills of the Rocky Mountain National Park (RMNP). Results will help inform atmospheric chemists and test a forecasting tool for the downwind transport of reduced nitrogen into a sensitive ecosystem. In this collaborative project between 2 institutions and 4 PIs, a 10-week field campaign is planned in the foothills of RMNP to determine (i) fluxes and deposition timescales of NH3 within 10 km downwind of large sources, and (ii) spatial distribution and partitioning of NHx ~100 km downwind of same sources. The main sampling platform is the University of Wyoming King Air (UWKA) research aircraft equipped with new measurement capabilities that allow for enhanced sampling strategies of gases and particulates. Gaseous species include reduced and oxidized nitrogen (NH3 and HNO3), methane (CH4), ethane (C2H6), carbon monoxide (CO), carbon dioxide (CO2) and water vapor (H2O), while particulates include aerosol concentration and size and their water-soluble species concentrations. CH4 and C2H6 allow to track the plume and distinguish between different source types. Integration of flight data with ground-based observations collected from mobile monitoring and existing sampling sites, provides a means to better interpret consistently available ground-based data in the future. Results will also contribute to improved representation of NH3 in transport models, help predict local air quality and inform stakeholders. Two graduate and several undergraduate students will obtain valuable hands-on experiences in a collaborative field campaign.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.