一个适用于地球系统模式(CAS-ESM)的在线气溶胶与大气化学分量模式(IAP-AACM)的发展与评估

地球系统模式是研究全球气候与生态环境变化问题的重要工具,气溶胶与大气化学模式负责为其中的大气环流模式提供与气候效应有关的气态化学物质和气溶胶成分。本文在全球嵌套网格空气质量预报模式系统的基础上发展了一个适用于中国科学院地球系统模式（CAS-ESM）耦合计算的气溶胶与大气化学分量模式（IAP-AACM）,采用简化的气相化学机制,不仅考虑了人为气溶胶,同时考虑了海盐、沙尘和二甲基硫等自然气溶胶及其前体物的在线排放。评估结果表明,IAP-AACM氧化剂插值计算可靠,采用简化机制和碳键机制（CBM-Z）模拟的差异较小。和观测的对比表明,得益于CAS-ESM的气溶胶双向反馈作用,简化版能够较好地抓住气溶胶及其前体物的空间分布,为IAP-AGCM提供可靠的气溶胶模拟。另外,简化版能大幅提升计算效率,满足CAS-ESM耦合长期积分的需求。为了在全球气候变化的研究中提供更完善的气溶胶模拟,未来考虑在IAP-AACM中增加氮化学和臭氧平流层化学机制。

Development and Evaluation of the Online Aerosol and Atmospheric Chemistry Model for the Chinese Academy of Sciences Earth System Model

The earth system model (ESM) is an important tool for analyzing global climate and ecological environment changes. The Aerosol and Atmospheric Chemistry Model (AACM) enables the simulation of gases and aerosols associated with the effects of climate change for further processing using the Atmospheric General Circulation Model (AGCM). On the basis of the Global Nested Grid Air Quality Prediction Model System, a simplified version of the AACM of the Institute of Atmospheric Physics (IAP-AACM) suitable for the ESM of the Chinese Academy of Sciences (CAS-ESM) is developed using a simplified gas-phase chemical mechanism. Not only anthropogenic aerosols but also natural aerosols and its precursors (e.g., sea salt, dust, and dimethyl sulfide) are considered. The evaluation showed that the IAP-AACM with simplified gas-phase chemical mechanism can reasonably simulate the spatial distribution of aerosols and precursor gases. The difference between the simplified version and the standard version with CBM-Z mechanism is small. The comparison of the obtained values with the observations shows that the simplified version captured the spatial distribution of aerosols and its precursors well and provided a reliable aerosol simulation for the IAP-AGCM in favor of two-way feedback. Furthermore, the simplified version can significantly improve the calculation efficiency and well satisfy the need for long-range integration of the CAS-ESM. To provide a more comprehensive aerosol simulation in the research on global climate change, the mechanism of nitrogen chemistry and the stratospheric chemistry of ozone will be considered in the IAP-AACM in the future.