Measurements of urban emissions of NOx and VOCs

城市氮氧化物和挥发性有机化合物排放的测量

• 批准号: 2544470
• 金额: --
• 依托单位: University of York
• 依托单位国家: 英国
• 项目类别: Studentship
• 财政年份: 2020
• 资助国家: 英国
• 起止时间: 2020 至 无数据
• 项目状态: 已结题
• 来源: https://gtr.ukri.org/projects?ref=studentship-2544470
• 关键词: Measurements; urban; emissions; NOx; VOCs

This project will, for the first time, link total measured emissions with direct vehicle exhaust emission measurements made within the flux footprint, thus allowing a detailed assessment of the performance of emission inventories and improved inventories to be developed. Emissions are measured via eddy covariance which utilises high time resolution measurements of NO, NO2, speciated VOCs and micrometeorological data from a tall tower site. Eddy covariance has been widely used to assess greenhouse gas budgets in rural/agricultural areas for many years but is more recently being used for air quality pollutants and in urban environments. NOx emissions measurements in London will be made over the period of the PhD at the BT tower in London. In addition, during two intensive filed campaigns in winter and summer 2021, the student will deploy a Selected Ion Flow Tube Mass Spectrometer (SIFT-MS, Voice 200 ultra, Syft Technologies) combined with Automated Gas Calibration Unit (AGCU) to determine the emissions of Benzene, Toluene, Isoprene, ethanol, methanol, C2-alklyl benzenes and C3-alkyl-benzenes using virtually disjunct eddy covariance (v-DEC). Emission will be calculated via classical and continuous wavelet transform eddy covariance techniques, the latter giving improved temporal information about the emissions.Footprint modelling links these local fluxes to the surface allowing them to be compared with emission inventories. The work builds on measurements made from the BT tower in 2017 which showed emission estimates from the NAEI being 20-30% lower than directly measured NOx flux, with the greatest discrepancy being on weekend daytime. The measurements are funded as part of the UKRI / NERC funded Integrated Research Observation System for Clean Air (OSCA) project.

该项目将首次将总测量的排放与通量足迹内进行的直接车辆排气排放测量联系起来，从而可以详细评估排放库存的性能和改进的库存。排放是通过涡流协方差测量的，该协方差利用了高塔站点的高时间分辨率测量值，NO2，指定的VOC和微气候数据。多年来，Eddy协方差已被广泛用于评估农村/农业地区的温室气预算，但最近被用于空气质量污染物和城市环境中。伦敦的NOX排放量测量将在伦敦BT塔的博士学位期间进行。此外，在2021年冬季和夏季的两次密集提交的活动中，学生将部署选定的离子流管质谱仪（SIFT-MS，Voice 200 Ultra，Syft Technologies）与自动气体校准单元（AGCU）相结合，以确定使用苯，甲酸，Isoprene，ethanol，chananol，chananol，C2--甲醇，C2-c2-c2-c2-nalole，C2-c2-c2-c2-nalole，C2--实际上是分离的eddy协方差（V-DEC）。发射将通过经典和连续的小波变换涡流协方差技术计算，后者提供了有关排放的时间信息。Footprint建模将这些局部通量与表面联系起来，从而将它们与排放清单进行比较。这项工作是建立在2017年由BT塔制定的测量基础上的，该测量表明，NAEI的排放估计比直接测量的NOX通量低20-30％，而周末白天的差异最大。这些测量是作为乌克里 / NERC资助的清洁空气（OSCA）项目综合研究观察系统的一部分资助的。