气候变化领域集成服务门户(CCPortal): An improved representation of aerosol mixing state for air quality-weather interactions

CCPortal

DOI	10.5194/acp-22-13527-2022
	An improved representation of aerosol mixing state for air quality-weather interactions
	Stevens, Robin; Ryjkov, Andrei; Majdzadeh, Mahtab; Dastoor, Ashu
发表日期	2022
ISSN	1680-7316
EISSN	1680-7324
起始页码	13527
结束页码	13549
卷号	22 期号:20 页码:23
英文摘要	We implement a detailed representation of aerosol mixing state in the Global Environmental Multiscale - Modelling Air quality and CHemistry (GEM-MACH) air quality and weather forecast model. Our mixing-state representation includes three categories: one for more hygroscopic aerosol, one for less hygroscopic aerosol with a high black carbon (BC) mass fraction, and one for less hygroscopic aerosol with a low BC mass fraction. The more detailed representation allows us to better resolve two different aspects of aerosol mixing state: differences in hygroscopicity due to aerosol composition and the amount of absorption enhancement of BC due to non-absorbing coatings. Notably, this three-category representation allows us to account for BC thickly coated with primary organic matter, which enhances the absorption of the BC but has a low hygroscopicity. We compare the results of the three-category representation (1L2B, (one hydrophilic, two hydrophobic)) with a simulation that uses two categories, split by hygroscopicity (HYGRO), and a simulation using the original size-resolved internally mixed assumption (SRIM). We perform a case study that is focused on North America during July 2016, when there were intense wildfires over northwestern North America. We find that the more detailed representation of the aerosol hygroscopicity in both 1L2B and HYGRO decreases wet deposition, which increases aerosol concentrations, particularly of less hygroscopic species. The concentration of PM2.5 increases by 23 % on average. We show that these increased aerosol concentrations increase cloud droplet number concentrations and cloud reflectivity in the model, decreasing surface temperatures. Using two categories based on hygroscopicity yields only a modest benefit in resolving the coating thickness on black carbon, however. The 1L2B representation resolves BC with thinner coatings than the HYGRO simulation, resulting in absorption aerosol optical depths that are 3 % less on average, with greater differences over strong anthropogenic source regions. We did not find strong subsequent effects of this decreased absorption on meteorology.
学科领域	Environmental Sciences; Meteorology & Atmospheric Sciences
语种	英语
WOS研究方向	Environmental Sciences & Ecology ; Meteorology & Atmospheric Sciences
WOS记录号	WOS:000869793000001
来源期刊	ATMOSPHERIC CHEMISTRY AND PHYSICS
文献类型	期刊论文
条目标识符	http://gcip.llas.ac.cn/handle/2XKMVOVA/273812
作者单位	Environment & Climate Change Canada; Universite de Montreal; Universite de Montreal; Environment & Climate Change Canada
推荐引用方式 GB/T 7714	Stevens, Robin,Ryjkov, Andrei,Majdzadeh, Mahtab,et al. An improved representation of aerosol mixing state for air quality-weather interactions[J],2022,22(20):23.
APA	Stevens, Robin,Ryjkov, Andrei,Majdzadeh, Mahtab,&Dastoor, Ashu.(2022).An improved representation of aerosol mixing state for air quality-weather interactions.ATMOSPHERIC CHEMISTRY AND PHYSICS,22(20),23.
MLA	Stevens, Robin,et al."An improved representation of aerosol mixing state for air quality-weather interactions".ATMOSPHERIC CHEMISTRY AND PHYSICS 22.20(2022):23.