气候变化领域集成服务门户(CCPortal): Aerosol Mass and Optical Properties, Smoke Influence on O3, and High NO3 Production Rates in a Western U.S. City Impacted by Wildfires

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DOI	10.1029/2020JD032791
	Aerosol Mass and Optical Properties, Smoke Influence on O3, and High NO3 Production Rates in a Western U.S. City Impacted by Wildfires
	Selimovic V.; Yokelson R.J.; McMeeking G.R.; Coefield S.
发表日期	2020
ISSN	2169897X
卷号	125 期号:16
英文摘要	Evaluating our understanding of smoke from wild and prescribed fires can benefit from downwind measurements that include inert tracers to test production and transport and reactive species to test chemical mechanisms. We characterized smoke from fires in coniferous forest fuels for >1,000 hr over two summers (2017 and 2018) at our Missoula, Montana, surface station and found a narrow range for key properties. ΔPM2.5/ΔCO was 0.1070 ± 0.0278 (g/g) or about half the age-independent ratios obtained at free troposphere elevations (0.2348 ± 0.0326). The average absorption Ångström exponent across both years was 1.84 ± 0.18, or about half the values available for very fresh smoke. Brown carbon (BrC) was persistent (~50% of absorption at 401 nm) in both years, despite differences in smoke age. ΔBC/ΔCO doubled from 2017 to 2018, but the average across 2 years was within 33% of recent airborne measurements, suggesting low sampling bias among platforms. Switching from a 1.0 to a 2.5 micron cutoff increased the mass scattering and mass absorption coefficients, suggesting often overlooked supermicron particles impact the optical properties of moderately aged smoke. O3 was elevated ~6 ppb on average over a full diurnal period when wildfire smoke was present, and smoke-associated O3 increases were highest (~9 pbb) at night, suggesting substantial upwind production. NOx was mostly local in origin. NOx spurred high rates of NO3 production, including in the presence of wildfire smoke (up to 2.44 ppb hr−1) and at least one nighttime BrC secondary formation event that could have impacted next-day photochemistry. ©2020. American Geophysical Union. All Rights Reserved.
英文关键词	biomass burning; nitrate radical; ozone; smoke impacts; wildfire smoke; wildfire smoke evolution
语种	英语
来源期刊	Journal of Geophysical Research: Atmospheres
文献类型	期刊论文
条目标识符	http://gcip.llas.ac.cn/handle/2XKMVOVA/185835
作者单位	Department of Chemistry, University of Montana, Missoula, MT, United States; Handix Scientific LLC, Boulder, CO, United States; Missoula City-County Health Department, Missoula, MT, United States
推荐引用方式 GB/T 7714	Selimovic V.,Yokelson R.J.,McMeeking G.R.,et al. Aerosol Mass and Optical Properties, Smoke Influence on O3, and High NO3 Production Rates in a Western U.S. City Impacted by Wildfires[J],2020,125(16).
APA	Selimovic V.,Yokelson R.J.,McMeeking G.R.,&Coefield S..(2020).Aerosol Mass and Optical Properties, Smoke Influence on O3, and High NO3 Production Rates in a Western U.S. City Impacted by Wildfires.Journal of Geophysical Research: Atmospheres,125(16).
MLA	Selimovic V.,et al."Aerosol Mass and Optical Properties, Smoke Influence on O3, and High NO3 Production Rates in a Western U.S. City Impacted by Wildfires".Journal of Geophysical Research: Atmospheres 125.16(2020).