Simulating Aerosol Size Distribution and Mass Concentration with Simultaneous Nucleation, Condensation/Coagulation, and Deposition with the GRAPES–CUACE

• Published in: Journal of Meteorological Research Vol. 32; no. 2; pp. 265 - 278
• Main Authors: Zhou, Chunhong, Shen, Xiaojing, Liu, Zirui, Zhang, Yangmei, Xin, Jinyuan
• Format: Journal Article
• Language: English
• Published: Beijing The Chinese Meteorological Society 01.04.2018; Jiangsu Collaborative Innovation Center of Climate Change,Nanjing 210093%State Key Laboratory of Severe Weather/Key Laboratory of Atmospheric Chemistry of China Meteorological Administration, Chinese Academy of Meteorological Sciences,Beijing 100081%Institute of Atmospheric Physics,Chinese Academy of Sciences,Beijing 100029; State Key Laboratory of Severe Weather/Key Laboratory of Atmospheric Chemistry of China Meteorological Administration, Chinese Academy of Meteorological Sciences,Beijing 100081
• Subjects: Atmospheric Protection/Air Quality Control/Air Pollution; Atmospheric Sciences; Earth and Environmental Science; Earth Sciences; Geophysics and Environmental Physics; Meteorology; Special Collection on Aerosol-Cloud-Radiation Interactions; GRAPES–CUACE; number size distribution; sectional multi-components; aerosol
• DOI: 10.1007/s13351-018-7116-8
• ISSN: 2095-6037

A coupled aerosol–cloud model is essential for investigating the formation of haze and fog and the interaction of aerosols with clouds and precipitation. One of the key tasks of such a model is to produce correct mass and number size distributions of aerosols. In this paper, a parameterization scheme for aerosol size distribution in initial emission, which took into account the measured mass and number size distributions of aerosols, was developed in the GRAPES–CUACE [Global/Regional Assimilation and PrEdiction System–China Meteorological Administration (CMA) Unified Atmospheric Chemistry Environment model]—an online chemical weather forecast system that contains microphysical processes and emission, transport, and chemical conversion of sectional multi-component aerosols. In addition, the competitive mechanism between nucleation and condensation for secondary aerosol formation was improved, and the dry deposition was also modified to be in consistent with the real depositing length. Based on the above improvements, the GRAPES–CUACE simulations were verified against observational data during 1–31 January 2013, when a series of heavy regional haze–fog events occurred in eastern China. The results show that the aerosol number size distribution from the improved experiment was much closer to the observation, whereas in the old experiment the number concentration was higher in the nucleation mode and lower in the accumulation mode. Meanwhile, the errors in aerosol number size distribution as diagnosed by its sectional mass size distribution were also reduced. Moreover, simulations of organic carbon, sulfate, and other aerosol components were improved and the overestimation as well as underestimation of PM 2.5 concentration in eastern China was significantly reduced, leading to increased correlation coefficient between simulated and observed PM 2.5 by more than 70%. In the remote areas where bad simulation results were produced previously, the correlation coefficient grew from 0.35 to 0.61, and the mean mass concentration went up from 43% to 87.5% of the observed value. Thus, the simulation of particulate matters in these areas has been improved considerably.