气候变化领域集成服务门户(CCPortal): Observation-based constraints on modeled aerosol surface area: implications for heterogeneous chemistry

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DOI	10.5194/acp-22-15449-2022
	Observation-based constraints on modeled aerosol surface area: implications for heterogeneous chemistry
	Bergin, Rachel A.; Harkey, Monica; Hoffman, Alicia; Moore, Richard H.; Anderson, Bruce; Beyersdorf, Andreas; Ziemba, Luke; Thornhill, Lee; Winstead, Edward; Holloway, Tracey; Bertram, Timothy H.
发表日期	2022
ISSN	1680-7316
EISSN	1680-7324
起始页码	15449
结束页码	15468
卷号	22 期号:23 页码:20
英文摘要	Heterogeneous reactions occurring at the surface of atmospheric aerosol particles regulate the production and lifetime of a wide array of atmospheric gases. Aerosol surface area plays a critical role in setting the rate of heterogeneous reactions in the atmosphere. Despite the central role of aerosol surface area, there are few assessments of the accuracy of aerosol surface area concentrations in regional and global models. In this study, we compare aerosol surface area concentrations in the EPA's Community Multiscale Air Quality (CMAQ) model with commensurate observations from the 2011 NASA flight-based DISCOVER-AQ (Deriving Information on Surface Conditions from COlumn and VERtically Resolved Observations Relevant to Air Quality) campaign. The study region includes the Baltimore and Washington, D.C. metropolitan area. Dry aerosol surface area was measured aboard the NASA P-3B aircraft using an ultra-high-sensitivity aerosol spectrometer (UHSAS). We show that modeled and measured dry aerosol surface area, Sa,mod and Sa,meas respectively, are modestly correlated (r2=0.52) and on average agree to within a factor of 2 (Sa,mod/Sa,meas=0.44) over the course of the 13 research flights. We show that Sa,mod/Sa,meas does not depend strongly on photochemical age or the concentration of secondary biogenic aerosol, suggesting that the condensation of low-volatility gas-phase compounds does not strongly affect model-measurement agreement. In comparison, there is strong agreement between measured and modeled aerosol number concentration (Nmod/Nmeas=0.87, r2=0.63). The persistent underestimate of Sa in the model, combined with strong agreement in modeled and measured aerosol number concentrations, suggests that model representation of the size distribution of primary emissions or secondary aerosol formed at the early stages of oxidation may contribute to the observed differences. For reactions occurring on small particles, the rate of heterogeneous reactions is a linear function of both Sa and the reactive uptake coefficient (gamma). To assess the importance of uncertainty in modeled Sa for the representation of heterogeneous reactions in models, we compare both the mean and the variance in Sa,mod/Sa,meas to those in gamma(N2O5)mod/gamma(N2O5)meas. We find that the uncertainty in model representation of heterogeneous reactions is primarily driven by uncertainty in the parametrization of reactive uptake coefficients, although the discrepancy between Sa,mod and Sa,meas is not insignificant. Our analysis suggests that model improvements to aerosol surface area concentrations, in addition to more accurate parameterizations of heterogeneous kinetics, will advance the representation of heterogeneous chemistry in regional models.
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:000893425500001
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/273765
作者单位	University of Wisconsin System; University of Wisconsin Madison; University of Wisconsin System; University of Wisconsin Madison; University of Wisconsin System; University of Wisconsin Madison; National Aeronautics & Space Administration (NASA); NASA Langley Research Center; Science Systems and Applications Inc; California State University System; California State University San Bernardino
推荐引用方式 GB/T 7714	Bergin, Rachel A.,Harkey, Monica,Hoffman, Alicia,et al. Observation-based constraints on modeled aerosol surface area: implications for heterogeneous chemistry[J],2022,22(23):20.
APA	Bergin, Rachel A..,Harkey, Monica.,Hoffman, Alicia.,Moore, Richard H..,Anderson, Bruce.,...&Bertram, Timothy H..(2022).Observation-based constraints on modeled aerosol surface area: implications for heterogeneous chemistry.ATMOSPHERIC CHEMISTRY AND PHYSICS,22(23),20.
MLA	Bergin, Rachel A.,et al."Observation-based constraints on modeled aerosol surface area: implications for heterogeneous chemistry".ATMOSPHERIC CHEMISTRY AND PHYSICS 22.23(2022):20.