title: Observations of Atmospheric Δ14CO2at the Global and Regional Background Sites in China: Implication for Fossil Fuel CO2Inputs.
abstract: Six months to more than one year of atmospheric Δ14CO2were measured in 2014-2015 at one global background site in Waliguan (WLG) and four regional background sites at Shangdianzi (SDZ), Lin'an (LAN), Longfengshan (LFS) and Luhuitou (LHT), China. The objectives of the study are to document the Δ14CO2levels at each site and to trace the variations in fossil fuel CO2(CO2ff) inputs at regional background sites. Δ14CO2at WLG varied from 7.1 ± 2.9‰ to 32.0 ± 3.2‰ (average 17.1 ± 6.8‰) in 2015, with high values generally in autumn/summer and low values in winter/spring. During the same period, Δ14CO2values at the regional background sites were found to be significantly (p < 0.05) lower than those at WLG, indicating different levels of CO2ffinputs at those sites. CO2ffconcentrations at LAN (12.7 ± 9.6 ppm) and SDZ (11.5 ± 8.2 ppm) were significantly (p < 0.05) higher than those at LHT (4.6 ± 4.3 ppm) in 2015. There were no significant (p > 0.05) seasonal differences in CO2ffconcentrations for the regional sites. Regional sources contributed in part to the CO2ffinputs at LAN and SDZ, while local sources dominated the trend observed at LHT. These data provide a preliminary understanding of atmospheric Δ14CO2and CO2ffinputs for a range of Chinese background sites.
authors: State Key Laboratory of Loess and Quaternary Geology, Institute of Earth Environment, Chinese Academy of Sciences , Xi'an, China.|Shaanxi Provincial Key Laboratory of Accelerator Mass Spectrometry Technology and Application, Xi'an AMS Center, Xi'an, China.
authors: Zhenchuan
authors: Z
authors: Niu
authors: State Key Laboratory of Loess and Quaternary Geology, Institute of Earth Environment, Chinese Academy of Sciences , Xi'an, China.|Shaanxi Provincial Key Laboratory of Accelerator Mass Spectrometry Technology and Application, Xi'an AMS Center, Xi'an, China.|Beijing Normal University , Beijing, China.
authors: Weijian
authors: W
authors: Zhou
authors: State Key Laboratory of Loess and Quaternary Geology, Institute of Earth Environment, Chinese Academy of Sciences , Xi'an, China.|Shaanxi Provincial Key Laboratory of Accelerator Mass Spectrometry Technology and Application, Xi'an AMS Center, Xi'an, China.
authors: Peng
authors: P
authors: Cheng
authors: State Key Laboratory of Loess and Quaternary Geology, Institute of Earth Environment, Chinese Academy of Sciences , Xi'an, China.|Shaanxi Provincial Key Laboratory of Accelerator Mass Spectrometry Technology and Application, Xi'an AMS Center, Xi'an, China.
authors: Shugang
authors: S
authors: Wu
authors: State Key Laboratory of Loess and Quaternary Geology, Institute of Earth Environment, Chinese Academy of Sciences , Xi'an, China.|Shaanxi Provincial Key Laboratory of Accelerator Mass Spectrometry Technology and Application, Xi'an AMS Center, Xi'an, China.
authors: Xuefeng
authors: X
authors: Lu
authors: State Key Laboratory of Loess and Quaternary Geology, Institute of Earth Environment, Chinese Academy of Sciences , Xi'an, China.|Shaanxi Provincial Key Laboratory of Accelerator Mass Spectrometry Technology and Application, Xi'an AMS Center, Xi'an, China.
authors: Xiaohu
authors: X
authors: Xiong
authors: State Key Laboratory of Loess and Quaternary Geology, Institute of Earth Environment, Chinese Academy of Sciences , Xi'an, China.|Shaanxi Provincial Key Laboratory of Accelerator Mass Spectrometry Technology and Application, Xi'an AMS Center, Xi'an, China.
authors: Hua
authors: H
authors: Du
authors: State Key Laboratory of Loess and Quaternary Geology, Institute of Earth Environment, Chinese Academy of Sciences , Xi'an, China.|Shaanxi Provincial Key Laboratory of Accelerator Mass Spectrometry Technology and Application, Xi'an AMS Center, Xi'an, China.
authors: Yunchong
authors: Y
authors: Fu
mesh_terms: D000393:Air Pollutants; D002245:Carbon Dioxide; D002681:China; D004784:Environmental Monitoring; D005579:Fossil Fuels
chemical_list: D000393:Air Pollutants; D005579:Fossil Fuels; D002245:Carbon Dioxide