大气气溶胶因其环境（健康）与气候效应备受关注，而新粒子生成是大气气溶胶的重要来源。目前关于新粒子生成的认识多基于欧美清洁大气环境，但我国大气复合污染环境下的新粒子生成机理仍不清楚。本项目计划通过详细对比我国长三角西部高污染地区和芬兰针叶林地区的新粒子生成事件，分析现有新粒子生成理论在我国大气复合污染环境下的适用性。利用南京大学SORPES观测站及芬兰针叶林地区SMEAR II观测站的长期观测数据（包括硫酸、高氧化态有机物、气溶胶/空气离子粒径谱、气象和痕量气体等数据），计算新粒子生成相关参数，建立数据集。通过对比分析，找出长三角西部地区和芬兰针叶林地区新粒子生成的差异。结合大气化学和气溶胶箱体模型MALTE-BOX模型模拟及敏感性实验，系统分析导致两个地区新粒子生成差异的关键因子及重要物理、化学过程，以期提高对于我国大气复合污染环境下新粒子生成机理的认识。

Atmospheric aerosols receive lots of attentions because of their environmental and climate effects. New particle formation (NPF) is one of important sources of aerosol. At present, the understanding of NPF is mostly based on the clean air environment in Europe or USA. However, the mechanism of NPF under complex air pollution in China is still unclear. This project plans to compare the NPF in the high-pollution areas of western YRD area and in the boreal forest of Finland and study the applicability of the classic NPF theory under complex air pollution in China. Based on the long-term observation data (e.g. sulfuric acid, highly oxygenated multifunctional compounds, aerosol/ion size distribution, meteorological condition and trace gases) collected from the SORPES station of Nanjing University and the SMEAR II station in the boreal forest of Finland, this project will calculate the parameters of NPF and set up the data sets. Through the comparison study, the differences of NPF in the western YRD and boreal forest in Finland will be found out. Combined with the simulation and sensitive tests by MALTE-BOX model, the key factors and physical/chemical processes leading to the differences of NPF at two sites will be analyzed in order to improve the understanding of NPF mechanism under complex air pollution in China.