气候变化领域集成服务门户(CCPortal): A revised mineral dust emission scheme in GEOS-Chem: Improvements in dust simulations over China

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DOI	10.5194/acp-21-4319-2021
	A revised mineral dust emission scheme in GEOS-Chem: Improvements in dust simulations over China
	Tian R.; Ma X.; Zhao J.
发表日期	2021
ISSN	1680-7316
起始页码	4319
结束页码	4337
卷号	21 期号:6
英文摘要	Mineral dust plays a significant role in climate change and air quality, but large uncertainties remain in terms of dust emission prediction. In this study, we improved treatment of the dust emission process in a global 3-D chemical transport model (GEOS-Chem v12.6.0), by incorporating the geographical variation of aerodynamic roughness length (Z0), smooth roughness length (Z0s) and soil texture and by introducing the Owen effect and the formulation of the sandblasting efficiency - by Lu and Shao (1999). To investigate the impact of the modifications incorporated in the model, several sensitivity simulations were performed for a severe dust storm during 27 March to 2 April 2015 over northern China. Results show that simulated threshold friction velocity is very sensitive to the updated Z0 and Z0s field, with the relative difference ranging from 10% to 60% compared to the original model with a uniform value. The inclusion of the Owen effect leads to an increase in surface friction velocity, which mainly occurs in the arid and semi-arid regions of northwest China. The substitution of a fixed value of - assumed in the original scheme with one varying with friction velocity and soil texture based on observations reduces - by 50% on average, especially over regions with sand texture. Comparisons of sensitivity simulations and measurements show that the revised scheme with the implementation of updates provides more realistic threshold friction velocities and PM10 mass concentrations. The performance of the improved model has been evaluated against surface PM10 observations as well as MODIS aerosol optical depth (AOD) values, showing that the spatial and temporal variation of mineral dust are better captured by the revised scheme. Due to the inclusion of the improvement, average PM10 concentrations at observational sites are more comparable to the observations, and the average mean bias (MB) and normalized mean bias (NMB) values are reduced from -196.29 μgm-3 and -52.79% to -47.72 μgm-3 and -22.46% respectively. Our study suggests that the erodibility factor, sandblasting efficiency and soil-related properties which are simply assumed in the empirical scheme may lack a physical mechanism and spatial temporal representativeness. Further study and measurements should be conducted to obtain a more realistic and detailed map of these parameters in order to improve dust representation in the model. © 2021 EDP Sciences. All rights reserved.
语种	英语
scopus关键词	aerosol; air quality; climate change; climate forcing; computer simulation; concentration (composition); dust; efficiency measurement; emission inventory; friction; MODIS; numerical model; optical depth; soil texture; three-dimensional modeling; China
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/247042
作者单位	Collaborative Innovation Center on Forecast and Evaluation of Meteorological Disasters (CIC-FEMD), Key Laboratory for Aerosol-Cloud-Precipitation of China Meteorological Administration, Nanjing University of Information Science and Technology, Nanjing, 210044, China
推荐引用方式 GB/T 7714	Tian R.,Ma X.,Zhao J.. A revised mineral dust emission scheme in GEOS-Chem: Improvements in dust simulations over China[J],2021,21(6).
APA	Tian R.,Ma X.,&Zhao J..(2021).A revised mineral dust emission scheme in GEOS-Chem: Improvements in dust simulations over China.ATMOSPHERIC CHEMISTRY AND PHYSICS,21(6).
MLA	Tian R.,et al."A revised mineral dust emission scheme in GEOS-Chem: Improvements in dust simulations over China".ATMOSPHERIC CHEMISTRY AND PHYSICS 21.6(2021).