气候变化领域集成服务门户(CCPortal): The impacts of wildfires on ozone production and boundary layer dynamics in California's Central Valley

CCPortal

DOI	10.5194/acp-22-9681-2022
	The impacts of wildfires on ozone production and boundary layer dynamics in California's Central Valley
	Pan, Keming; Faloona, Ian C.
发表日期	2022
ISSN	1680-7316
EISSN	1680-7324
起始页码	9681
结束页码	9702
卷号	22 期号:14 页码:22
英文摘要	We investigate the role of wildfire smoke on ozone photochemical production (P(O-3)) and atmospheric boundary layer (ABL) dynamics in California's Central Valley during June-September from 2016 to 2020. Wildfire events are identified by the Hazard Mapping System (HMS) and the Hybrid Single Particle Lagrangian Integrated Trajectory Model (HYSPLIT). Air quality and meteorological data are analyzed from 10 monitoring sites operated by the California Air Resources Board (CARB) across the Central Valley. On average, wildfires were found to influence air quality in the Central Valley on about 20% of the total summer days of the study. During wildfire-influenced periods, maximum daily 8 h averaged (MDA8) O-3 was enhanced by about 5.5 ppb or 10% of the median MDA8 (once corrected for the slightly warmer temperatures) over the entire valley. Overall, nearly half of the total exceedances of the National Ambient Air Quality Standards (NAAQS) where MDA8 O-3 > 70 ppb occur under the influence of wildfires, and approximately 10% of those were in exceedance by 5 ppb or less indicating circumstances that would have been in compliance with the NAAQS were it not for wildfire emissions. The photochemical ozone production rate calculated from the modified Leighton relationship was also found to be higher by 50% on average compared with non-fire periods despite the average diminution of j (NO2) by similar to 7% due to the shading effect of the wildfire smoke plumes. Surface heat flux measurements from two AmeriFlux sites in the northern San Joaquin Valley show midday surface buoyancy fluxes decrease by 30% on average when influenced by wildfire smoke. Similarly, afternoon peak ABL heights measured from a radio acoustic sounding system (RASS) located in Visalia in the southern San Joaquin Valley were found to decrease on average by 80m (similar to 15 %) with a concomitant reduction of downwelling shortwave radiation of 54Wm(-2), consistent with past observations of the dependence of boundary laye heights on insolation.
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:000832641200001
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/273299
作者单位	University of California System; University of California Davis; University of California System; University of California Davis
推荐引用方式 GB/T 7714	Pan, Keming,Faloona, Ian C.. The impacts of wildfires on ozone production and boundary layer dynamics in California's Central Valley[J],2022,22(14):22.
APA	Pan, Keming,&Faloona, Ian C..(2022).The impacts of wildfires on ozone production and boundary layer dynamics in California's Central Valley.ATMOSPHERIC CHEMISTRY AND PHYSICS,22(14),22.
MLA	Pan, Keming,et al."The impacts of wildfires on ozone production and boundary layer dynamics in California's Central Valley".ATMOSPHERIC CHEMISTRY AND PHYSICS 22.14(2022):22.