气候变化领域集成服务门户(CCPortal): Modeling stratospheric intrusion and trans-Pacific transport on tropospheric ozone using hemispheric CMAQ during April 2010 - Part 2: Examination of emission impacts based on the higher-order decoupled direct method

CCPortal

DOI	10.5194/acp-20-3397-2020
	Modeling stratospheric intrusion and trans-Pacific transport on tropospheric ozone using hemispheric CMAQ during April 2010 - Part 2: Examination of emission impacts based on the higher-order decoupled direct method
	Itahashi S.; Mathur R.; Hogrefe C.; L. Napelenok S.; Zhang Y.
发表日期	2020
ISSN	1680-7316
起始页码	3397
结束页码	3413
卷号	20 期号:6
英文摘要	The state-of-the-science Community Multiscale Air Quality (CMAQ) modeling system, which has recently been extended for hemispheric-scale modeling applications (referred to as H-CMAQ), is applied to study the trans-Pacific transport, a phenomenon recognized as a potential source of air pollution in the US, during April 2010. The results of this analysis are presented in two parts. In the previous paper (Part 1), model evaluation for tropospheric ozone (O3) was presented and an air mass characterization method was developed. Results from applying this newly established method pointed to the importance of emissions as the factor to enhance the surface O3 mixing ratio over the US. In this subsequent paper (Part 2), emission impacts are examined based on mathematically rigorous sensitivity analysis using the higher-order decoupled direct method (HDDM) implemented in H-CMAQ. The HDDM sensitivity coefficients indicate the presence of a NOx-sensitive regime during April 2010 over most of the Northern Hemisphere. By defining emission source regions over the US and east Asia, impacts from these emission sources are examined. At the surface, during April 2010, the emission impacts of the US and east Asia are comparable over the western US with a magnitude of about 3 ppbv impacts on monthly mean O3 all-hour basis, whereas the impact of domestic emissions dominates over the eastern US with a magnitude of about 10 ppbv impacts on monthly mean O3. The positive correlation (rCombining double low line0.63) between surface O3 mixing ratios and domestic emission impacts is confirmed. In contrast, the relationship between surface O3 mixing ratios and emission impacts from east Asia exhibits a flat slope when considering the entire US. However, this relationship has strong regional differences between the western and eastern US; the western region exhibits a positive correlation (rCombining double low line0.36-0.38), whereas the latter exhibits a flat slope (r < 0.1). Based on the comprehensive evaluation of H-CMAQ, we extend the sensitivity analysis for O3 aloft. The results reveal the significant impacts of emissions from east Asia on the free troposphere (defined as 750 to 250 hPa) over the US (impacts of more than 5 ppbv) and the dominance of stratospheric air mass on upper model layer (defined as 250 to 50 hPa) over the US (impacts greater than 10 ppbv). Finally, we estimate changes of trans-Pacific transport by taking into account recent emission trends from 2010 to 2015 assuming the same meteorological condition. The analysis suggests that the impact of recent emission changes on changes in the contribution of trans-Pacific transport to US O3 levels was insignificant at the surface level and was small (less than 1 ppbv) over the free troposphere.. © 2020 BMJ Publishing Group. All rights reserved.
语种	英语
scopus关键词	atmospheric modeling; atmospheric pollution; atmospheric transport; emission; pollutant source; stratosphere; troposphere; United States
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/247900
作者单位	Environmental Science Research Laboratory, Central Research Institute of Electric Power Industry (CRIEPI), 1646 Abiko, Abiko, Chiba, 270-1194, Japan; Environmental Protection Agency (EPA), Computational Exposure Division, National Exposure Research Laboratory_aor4 Office of Research and Development, Research Triangle Park, NC 27711, United States; Department of Marine Earth, and Atmospheric Sciences (MEAS), North Carolina State University (NCSU), Campus Box 8208, Raleigh, NC 27695, United States; Department of Civil and Environmental Engineering, Northeastern University, Boston, MA 02115, United States
推荐引用方式 GB/T 7714	Itahashi S.,Mathur R.,Hogrefe C.,et al. Modeling stratospheric intrusion and trans-Pacific transport on tropospheric ozone using hemispheric CMAQ during April 2010 - Part 2: Examination of emission impacts based on the higher-order decoupled direct method[J],2020,20(6).
APA	Itahashi S.,Mathur R.,Hogrefe C.,L. Napelenok S.,&Zhang Y..(2020).Modeling stratospheric intrusion and trans-Pacific transport on tropospheric ozone using hemispheric CMAQ during April 2010 - Part 2: Examination of emission impacts based on the higher-order decoupled direct method.ATMOSPHERIC CHEMISTRY AND PHYSICS,20(6).
MLA	Itahashi S.,et al."Modeling stratospheric intrusion and trans-Pacific transport on tropospheric ozone using hemispheric CMAQ during April 2010 - Part 2: Examination of emission impacts based on the higher-order decoupled direct method".ATMOSPHERIC CHEMISTRY AND PHYSICS 20.6(2020).