气候变化领域集成服务门户(CCPortal): Seasonal variations of atmospheric CH4 at Jingdezhen station in Central China: Understanding the regional transport and its correlation with CO2 and CO

CCPortal

DOI	10.1016/j.atmosres.2020.104982
	Seasonal variations of atmospheric CH4 at Jingdezhen station in Central China: Understanding the regional transport and its correlation with CO2 and CO
	Xia L.; Zhang G.; Zhan M.; Li B.; Kong P.
发表日期	2020
ISSN	0169-8095
卷号	241
英文摘要	Greenhouse gases observation networks have been extensively established in the eastern, southern, western, and northern China, but rare in the developing central China. We conducted in-situ measurement of atmospheric CH4 mixing ratios with high precision at JDZ (Jingdezhen) station (29.37°N, 117.22°E, 87.3 m a.s.l) in central China between December 2017 and November 2018. The “regionally representative data” and “polluted events” are separated from the complete dataset, based on the analysis of diurnal discrepancy among different levels, the impacts of wind directions and speeds, and the statistical identification procedure. The average CH4 mixing ratio of regionally representative compositions during the study period was 2037.4 ppb, lower than that of polluted conditions (2086.3 ppb). The lowest levels of CH4 for regionally representative conditions are observed in summer, while highest values are obtained during June–August for polluted events. Cluster analysis of backward trajectories indicated that air-mass transport arising from northwestern China, eastern China and Jiangxi made the significant contribution to the variability in regionally representative air. Air masses passing through Jiangxi province and Yangtze River Delta (YRD) regions carried the polluted air with higher CH4 mixing ratios to the observational station in summer, probably owing to large quantities of CH4 emission from rice cultivation over these areas. △CH4 and △CO exhibit strong correlations in all month during the study period. Moreover, the △CO/△CH4 ratio showed the distinct seasonal characteristics, with the rapid decrease from the peak (2.74 ± 0.05, ppb/ppb) in January to the trough (0.40 ± 0.02, ppb/ppb) in July, and then the gradual increase to high levels in winter. It is possibly attributed to the maximum CH4 emission during summertime and the maximum CO emission during wintertime, as well as the significantly faster reaction rate of CO with OH in summer. The enhancements of CH4 (△CH4) and CO2 (△CO2) in polluted conditions relative to the regionally representative conditions present strong correlation only in winter, with the △CH4 /△CO2 slope of (3.92 ± 0.08) ppb/ppm, similar with the average △CH4 /△CO2 ratio observed in winter (4.15 ± 0.40, ppb/ppm) reported for LAN regional station during 2007 and 2013. © 2020 Elsevier B.V.
关键词	Carbon dioxide Cluster analysis Greenhouse gases Meteorology Mixing Backward trajectory Central chinas Identification procedure In-situ measurement Observation networks Seasonal characteristics Strong correlation Yangtze river delta Atmospheric movements atmospheric chemistry atmospheric pollution carbon dioxide carbon monoxide cluster analysis correlation emission inventory greenhouse gas in situ measurement methane mixing ratio pollutant transport seasonal variation wind direction wind velocity China Jiangxi Jingdezhen
语种	英语
来源机构	Atmospheric Research
文献类型	期刊论文
条目标识符	http://gcip.llas.ac.cn/handle/2XKMVOVA/132461
推荐引用方式 GB/T 7714	Xia L.,Zhang G.,Zhan M.,et al. Seasonal variations of atmospheric CH4 at Jingdezhen station in Central China: Understanding the regional transport and its correlation with CO2 and CO[J]. Atmospheric Research,2020,241.
APA	Xia L.,Zhang G.,Zhan M.,Li B.,&Kong P..(2020).Seasonal variations of atmospheric CH4 at Jingdezhen station in Central China: Understanding the regional transport and its correlation with CO2 and CO.,241.
MLA	Xia L.,et al."Seasonal variations of atmospheric CH4 at Jingdezhen station in Central China: Understanding the regional transport and its correlation with CO2 and CO".241(2020).