气候变化领域集成服务门户(CCPortal): Simulating nitrate formation mechanisms during PM2.5 events in Taiwan and their implications for the controlling direction

CCPortal

DOI	10.1016/j.atmosenv.2021.118856
	Simulating nitrate formation mechanisms during PM2.5 events in Taiwan and their implications for the controlling direction
	Chuang M.-T.; Wu C.-F.; Lin C.-Y.; Lin W.-C.; Chou C.C.-K.; Lee C.-T.; Lin T.-H.; Fu J.S.; Kong S.S.-K.
发表日期	2022
ISSN	1352-2310
卷号	269
英文摘要	The long-term downward trend of NOX concentrations does not reflect the reduction of nitrate (NO3−) in Taiwan. Instead, the proportion of NO3− in PM2.5 increased in recent years. To probe the increasing importance of NO3− in PM2.5, this study applied the WRF/CMAQ modeling system to implement a simulation from 16 March 2017 to 30 April 2017, in which 5 p.m.2.5 events with daily average concentrations ≥35 μg m−3 and their corresponding correlation coefficients (R) of simulated and observed PM2.5 above 0.6 were selected for analysis. During the daytime, the reaction of NO2 and OH contributed more than 90% of the total HNO3. After sunset, the high concentrations of NO3 and N2O5 peaked, followed soon by the simultaneous rise of NO3−, aerosol water content, and HNO3 concentrations around midnight, which indicated that the heterogeneous reaction was the main formation mechanism of NO3−, accounting for approximately 30%–90% of total HNO3. At nighttime, the daytime-formed gaseous phase NO3− condensed, and low wind and low boundary layer height favored accumulation; therefore, PM2.5 peaked around the midnight period to the early morning. The sensitivity test showed that doubling and halving the NOX and NH3 emissions could directly lead to the highest production and reduction of NO3−, respectively, followed by doubling and halving NMHC emissions, which caused the highest and lowest O3 concentrations. The correlation analysis of the simulation results showed that the daytime maximum O3 and HNO3 were highly correlated. The relationships between daytime maximum O3, nighttime maximum NO3, N2O5, and HNO3 in pairs were also moderately to highly correlated. This study implies that in addition to direct reduction of NOX or NH3 emissions, controlling O3 is possibly another useful strategy to reduce NO3−. Because NOX emission reduction could conflict with controlling O3, this study suggests to re-examine the determination of NOX-limited and VOCS-limited regions in order to develop strategies for reducing NOX emission and O3 simultaneously. © 2021 Elsevier Ltd
关键词	Nitrate formation mechanism O3 PM2.5 WRF/CMAQ modeling
语种	英语
scopus关键词	Ammonia; Boundary layer flow; Boundary layers; Emission control; Nitrogen oxides; % reductions; Doublings; Formation mechanism; Highly-correlated; Modelling systems; Nitrate formation mechanism; O3; PM 2.5; Pm2.5; WRF/CMAQ modeling; Nitrates; boundary layer; correlation; emission; formation mechanism; modeling; nitrate; reduction; Taiwan
来源期刊	ATMOSPHERIC ENVIRONMENT
文献类型	期刊论文
条目标识符	http://gcip.llas.ac.cn/handle/2XKMVOVA/248105
作者单位	Research Center for Environmental Changes, Academia Sinica, Taipei, 11529, Taiwan; Department of Public Health, National Taiwan University, Taipei, 10055, Taiwan; Graduate Institute of Environmental Engineering, National Central University, Taoyuan, 32001, Taiwan; Center for Space and Remote Sensing Research, National Central University, Taoyuan, Taiwan; Department of Civil and Environmental Engineering, University of Tennessee, Knoxville, TN 37996, United States; Department of Atmospheric Sciences, National Central University, Taoyuan, 32001, Taiwan
推荐引用方式 GB/T 7714	Chuang M.-T.,Wu C.-F.,Lin C.-Y.,et al. Simulating nitrate formation mechanisms during PM2.5 events in Taiwan and their implications for the controlling direction[J],2022,269.
APA	Chuang M.-T..,Wu C.-F..,Lin C.-Y..,Lin W.-C..,Chou C.C.-K..,...&Kong S.S.-K..(2022).Simulating nitrate formation mechanisms during PM2.5 events in Taiwan and their implications for the controlling direction.ATMOSPHERIC ENVIRONMENT,269.
MLA	Chuang M.-T.,et al."Simulating nitrate formation mechanisms during PM2.5 events in Taiwan and their implications for the controlling direction".ATMOSPHERIC ENVIRONMENT 269(2022).