Investigation of East Asian emissions of CFC-11 using atmospheric observations in Taiwan

Adcock, Karina ORCID:, Ashfold, Matthew J., Chou, Charles, Gooch, Lauren, Hanif, Nofrazin Mohd, Laube, Johannes, Oram, David, Ou-Yang, Chang-Feng, Panagi, Marios, Sturges, Bill ORCID: and Reeves, Claire ORCID: (2020) Investigation of East Asian emissions of CFC-11 using atmospheric observations in Taiwan. Environmental Science & Technology, 54 (7). pp. 3814-3822. ISSN 0013-936X

[thumbnail of Accepted_Manuscript]
PDF (Accepted_Manuscript) - Accepted Version
Download (732kB) | Preview


Recent findings of an unexpected slowdown in the decline of CFC-11 mixing ratios in the atmosphere have led to the conclusion that global CFC-11 emissions have increased over the past decade and have been attributed in part to eastern China. This study independently assesses these findings by evaluating enhancements of CFC-11 mixing ratios in air samples collected in Taiwan between 2014 and 2018. Using the NAME (Numerical Atmospheric Modeling Environment) particle dispersion model, we find the likely source of the enhanced CFC-11 observed in Taiwan to be East China. Other halogenated trace gases were also measured, and there were positive interspecies correlations between CFC-11 and CHCl3, CCl4, HCFC-141b, HCFC-142b, CH2Cl2, and HCFC-22, indicating co-location of the emissions of these compounds. These correlations in combination with published emission estimates of CH2Cl2 and HCFC-22 from China, and of CHCl3 and CCl4 from eastern China, are used to estimate CFC-11 emissions. Within the uncertainties, these estimates do not differ for eastern China and the whole of China, so we combine them to derive a mean estimate that we term as being from "(eastern) China". For 2014-2018, we estimate an emission of 19 ± 5 Gg year-1 (gigagrams per year) of CFC-11 from (eastern) China, approximately one-quarter of global emissions. Comparing this to previously reported CFC-11 emissions estimated for earlier years, we estimate CFC-11 emissions from (eastern) China to have increased by 7 ± 5 Gg year-1 from the 2008-2011 average to the 2014-2018 average, which is 50 ± 40% of the estimated increase in global CFC-11 emissions and is consistent with the emission increases attributed to this region in an earlier study.

Item Type: Article
Additional Information: Funding Information: This work was supported by NERC IOF Awards NE/J016047/1 and NE/J016012/1. This work was also supported by Sources and Impacts of Short-Lived Anthropogenic Chlorine (SISLAC) NE/R001782/1. K.E.A. was funded by the UK Natural Environment Research Council through the EnvEast Doctoral Training Partnership (Grant NE/L002582/1). N.M.H. was funded through a Ph.D. studentship by the Ministry of Education Malaysia (MOE) and Universiti Kebangsaan Malaysia (UKM). J.C.L. received funding from the UK Natural Environment Research Council (Research Fellowship NE/I021918/1) and ERC project EXCITE (EXC3ITE-678904-ERC-2015-STG). L.J.G. received funding from the UK Natural Environment Research Council (Studentship NE/1210143). C.C.-K.C. received funding from the Academia Sinica and the Ministry of Science and Technology of Taiwan through Grant 105-2111-M-001-005-MY3 to support the sampling activities at Cape Fuguei Research Station. Acknowledgements: The authors are grateful for the work of the NOAA-ESRL Global Monitoring Division who provided the Manua Loa data. The authors acknowledge use of the NAME atmospheric dispersion model and associated NWP meteorological data sets made available by the UK Met Office. The authors also acknowledge the significant storage resources and analysis facilities made available on JASMIN by STFC CEDA along with the corresponding support teams.
Uncontrolled Keywords: chemistry(all),environmental chemistry ,/dk/atira/pure/subjectarea/asjc/1600
Faculty \ School: Faculty of Science > School of Environmental Sciences
University of East Anglia Research Groups/Centres > Theme - ClimateUEA
Faculty of Science
UEA Research Groups: Faculty of Science > Research Groups > Centre for Ocean and Atmospheric Sciences
Related URLs:
Depositing User: LivePure Connector
Date Deposited: 10 Mar 2020 10:20
Last Modified: 13 Apr 2023 13:58
DOI: 10.1021/acs.est.9b06433


Downloads per month over past year

Actions (login required)

View Item View Item