Articles | Volume 14, issue 9
Atmos. Chem. Phys., 14, 4779–4791, 2014
Atmos. Chem. Phys., 14, 4779–4791, 2014

Research article 14 May 2014

Research article | 14 May 2014

Sulfur hexafluoride (SF6) emissions in East Asia determined by inverse modeling

X. Fang1,2, R. L. Thompson1, T. Saito3, Y. Yokouchi3, J. Kim4,5, S. Li4,6, K. R. Kim4,6, S. Park7, F. Graziosi8, and A. Stohl1 X. Fang et al.
  • 1Norwegian Institute for Air Research, Kjeller, Norway
  • 2State Key Joint Laboratory for Environmental Simulation and Pollution Control, College of Environmental Sciences and Engineering, Peking University, Beijing, China
  • 3National Institute for Environmental Studies, Tsukuba, Japan
  • 4School of Earth and Environmental Sciences, Seoul National University, Seoul, South Korea
  • 5Scripps Institution of Oceanography, University of California at San Diego, La Jolla, California, USA
  • 6Research Institute of Oceanography, Seoul National University, Seoul, South Korea
  • 7Department of Oceanography, Kyungpook National University, Sangju, South Korea
  • 8University of Urbino, Urbino, Italy

Abstract. Sulfur hexafluoride (SF6) has a global warming potential of around 22 800 over a 100-year time horizon and is one of the greenhouse gases regulated under the Kyoto Protocol. Around the year 2000 there was a reversal in the global SF6 emission trend, from a decreasing to an increasing trend, which was likely caused by increasing emissions in countries that are not obligated to report their annual emissions to the United Nations Framework Convention on Climate Change. In this study, SF6 emissions during the period 2006–2012 for all East Asian countries – including Mongolia, China, Taiwan, North Korea, South Korea and Japan – were determined by using inverse modeling and in situ atmospheric measurements. We found that the most important sources of uncertainty associated with these inversions are related to the choice of a priori emissions and their assumed uncertainty, the station network as well as the meteorological input data. Much lower uncertainties are due to seasonal variability in the emissions, inversion geometry and resolution, and the measurement calibration scale. Based on the results of these sensitivity tests, we estimate that the total SF6 emission in East Asia increased rapidly from 2404 ± 325 Mg yr−1 in 2006 to 3787 ± 512 Mg yr−1 in 2009 and stabilized thereafter. China contributed 60–72% to the total East Asian emission for the different years, followed by South Korea (8–16%), Japan (5–16%) and Taiwan (4–7%), while the contributions from North Korea and Mongolia together were less than 3% of the total. The per capita SF6 emissions are highest in South Korea and Taiwan, while the per capita emissions for China, North Korea and Japan are close to global average. During the period 2006–2012, emissions from China and from South Korea increased, while emissions from Taiwan and Japan decreased overall.

Final-revised paper