Liu Mingxu, Song Yu, Wang Tiantian, Dang Xinyi, Shang Fang, Jin Xipeng, Du Mile, Wang Weigang, Sun Yele, Zhang Qiang, Kang Ling, Cai Xuhui, Zhang Hongsheng, Zhu Tong
State Key Joint Laboratory of Environmental Simulation and Pollution Control, College of Environmental Sciences and Engineering, Peking University, Beijing 100871, China.
State Key Laboratory for Structural Chemistry of Unstable and Stable Species, Beijing National Laboratory for Molecular Sciences (BNLMS), CAS Research/ Education Center for Excellence in Molecular Sciences, Institute of Chemistry, Chinese Academy of Sciences, Beijing 100190, China.
PNAS Nexus. 2024 Jul 25;3(8):pgae291. doi: 10.1093/pnasnexus/pgae291. eCollection 2024 Aug.
Atmospheric sulfate aerosols contribute significantly to air pollution and climate change. Sulfate formation mechanisms during winter haze events in northern China have recently received considerable attention, with more than 10 studies published in high-impact journals. However, the conclusions from in-field measurements, laboratory studies, and numerical simulations are inconsistent and even contradictory. Here, we propose a physically based yet simple method to clarify the debate on the dominant sulfate formation pathway. Based on the hazes evolving in the synoptic scale, first, a characteristic sulfate formation rate is derived using the Eulerian mass conservation equation constrained by in situ observations. Then, this characteristic value is treated as a guideline to determine the dominant sulfate formation pathway with a 0D chemical box model. Our observation-derived results establish a linkage between studies from laboratory experiments and chemical transport model simulations. A convergent understanding could therefore be reached on sulfate formation mechanisms in China's wintertime haze. This method is universal and can be applied to various haze conditions and different secondary products.
大气硫酸盐气溶胶对空气污染和气候变化有重大影响。中国北方冬季霾事件期间的硫酸盐形成机制最近受到了相当多的关注，已有10多篇研究发表在高影响力期刊上。然而，实地测量、实验室研究和数值模拟得出的结论并不一致，甚至相互矛盾。在此，我们提出一种基于物理但简单的方法来厘清关于主要硫酸盐形成途径的争论。基于在天气尺度上演变的霾，首先，利用受现场观测约束的欧拉质量守恒方程推导出特征硫酸盐形成速率。然后，将该特征值作为指导，用零维化学箱模型确定主要的硫酸盐形成途径。我们基于观测得出的结果建立了实验室实验研究与化学传输模型模拟之间的联系。因此，对于中国冬季霾中的硫酸盐形成机制可以达成趋同的理解。该方法具有通用性，可应用于各种霾条件和不同的二次产物。
