Improving Secondary Organic Aerosol (SOA) Models by Comparison to Chamber and Ambient Data and by Uncertainty and Sensitivity Analysis

该项目将评估和比较预测环境空气中二次有机气溶胶(SOA)形成的模型。当人类活动和植物排放的气相化合物氧化并凝结成非常小的颗粒时，大气中就会形成SOA。这些小颗粒可能会影响气候、空气质量和大气能见度。这项研究的三个主要目标是：(1)对不同的SOA模型进行相互比较，并将它们与大气相关的实验室测量和大气测量进行比较；(2)对模型进行严格的不确定性分析，以便了解模型测量差异的重要性；以及(3)进行全面的敏感性分析，以探索对模型结果有影响的模型配置和/或参数，如气溶胶质量和氧碳比。测量。几种化学机制的形成，包括显式的气相无机化学和与前驱体的反应，连续氧化，气到颗粒的分配，以及多相和凝聚相反应。模型的性能将通过与波士顿学院潜在的气溶胶质量(PAM)室和加州理工学院环境室的实验室测量结果进行比较，以及与2013年6月至7月在阿拉巴马州森特维尔森林茂密地区进行南方氧化物和气溶胶研究(SOAS)期间收集的环境现场数据进行比较来评估。

This project will evaluate and compare models that predict the formation of secondary organic aerosol (SOA) in ambient air. SOA are formed in the atmosphere when gas-phase compounds, emitted from human activities and from plants, oxidize and condense into very small particles. These small particles may affect climate, air quality, and atmospheric visibility. Improved modeling of SOA formation will lead to improvements in air quality and climate models.This research has three primary objectives: (1) to conduct inter-comparisons of different SOA models and test them against atmospheric relevant laboratory measurements and atmospheric measurements; (2) to do a rigorous uncertainty analysis of the models so that the significance of model-measurement differences can be understood; and (3) to perform a comprehensive sensitivity analysis to explore the influential model configurations and/or parameters for the model results of interest, such as aerosol mass and oxygen to carbon ratio. measurements. Several chemical mechanisms of SOA formation will be considered, including an explicit gas-phase inorganic chemistry and the reactions with the SOA precursors, continuous oxidation, gas-to-particle partitioning, and heterogeneous and condensed-phase reactions. Model performance will be evaluated by comparisons with laboratory measurements from the Potential Aerosol Mass (PAM) chambers at both Boston College and the environmental chamber at the California Institute of Technology, and by comparisons with ambient field data collected during the Southern Oxidant & Aerosol Study (SOAS), at a site located in a heavily forested area in Centreville, AL during June and July in 2013.