Atmospheric Monitoring New emissions of forbidden ozone-depleting CFC-11 detected? Christian Heusser und Franziska Jud 18.12.2018

General: Chlorofluorocarbons CCl3F CCl2F2 CF2Cl-CFCl2 CH3CCl3 CCl4 Known as CFC-11 CFC-12 CFC-113 Methyl chloroform Tetrachlorocarbon Lifetime (years) 52 102 93 5 26 Atmospheric Annual Mean Mole Fractions 2012 (ppt) 235.5 527.5 73.6 5.2 84.2 MW / Da 136 120 186 132 152 Cooling agents in fridges Blowing agents in polyurethane foams Non-toxic Ozone depletion in the stratosphere Greenhouse Gases L.J. Carpenter and S. Reimann, Ozone-Depleting Substances (ODSs) and Other Gases of Interest to the Montreal Protocol, Chapter 1 in Scientific Assessment of Ozone Depletion: 2014, Global Ozone Research and Monitoring Project – Report No. 55, World Meteorological Organization, Geneva, 2014, p 1.10-1.17 M. J. Molina and F. S. Rowland, Nature, 1974, 249, 810 Christian Heusser und Franziska Jud 18.12.2018

Montreal Protocol Signed in 1987, ratified by 197 countries Europe / Northern America: phase-out of CFC production by 1996 (Non-Article 5 countries) Developing countries: phase-out delayed until 1999 (Article 5 countries) Complete phase-out of CFC production by 2010 United Nations Environmental Programme, Handbook for the Montreal Protocol on Substances that Deplete the Ozone layer, 12th edition, 2018 Christian Heusser und Franziska Jud 18.12.2018

CFC-11: global background concentration source: https://www.esrl.noaa.gov/gmd/hats/combined/CFC11.html, last accessed: 16.12.2018 Christian Heusser und Franziska Jud 18.12.2018

CFC-11: new emissions since 2012? 2002 – 2012: steady decrease of atmospheric CFC-11 by -2.1±0.3 ppt/yr 2015 – 2017: decrease of atmospheric CFC- 11 slowed to -1.0±0.2 ppt/yr Reported production of CFC-11 is close to zero since 2006 Red lines: Northern hemisphere Blue lines: Southern hemisphere Grey lines: projections based on World Meteorological Organization scenarios Montzka et al., Nature, 2018, 557, 413 Christian Heusser und Franziska Jud 18.12.2018

Advanced Global Atmospheric Gases Experiment (AGAGE) 10 primary measurement stations around the world, 3 affiliate stations Prinn et al., Earth Syst. Sci. Data, 2018, 10, 985 Christian Heusser und Franziska Jud 18.12.2018

GC-multidetector system Alternating measurement of standard and unknown sample every 20 mins (36 unknown samples per day) 3 GC systems: 2 ECD systems and 1 FID ECD A: CFC-12, N2O, carrier gas: Ar/CH4, sample loop volume 2 mL) ECD B: CFC-11, CFC-113, CH3CCl3, CCl4 (carrier gas: Ar/CH4, sample loop volume 4.5 mL) FID (CH4, carrier gas N2, sample loop volume 10 mL) Prinn et al., J. Geophys. Res., 2000, 105 (D14), 17751 Christian Heusser und Franziska Jud 18.12.2018

GC-ECD A radioactive β-emitter (63Ni) produces a constant current Analyte molecules with a high electron affinity (e.g. halocarbons) capture electrons and reduce the constant current Identification of different CFCs by GC retention time L.S. Ettre and P. J. T Morris, LCGC North America, 2007, 25, 164 Christian Heusser und Franziska Jud 18.12.2018

GC-MS Alternating measurements of standard and unknown samples every 60 mins (12 unknown samples per day) Sampling: sample volume: 2L Preconcentration in a cryotrap at -165°C Separation and detection on a quadrupole GC-MS with EI ionization Sensitivity: 0.01 ppt (theoretical LOD), 0.1 ppt (practical LOD) for 2L air sample Sample volume needed to detect an amount of 1 ppt of CFC-11 above the baseline: 0.2 L needed for an LOD of 1 ppt, 0.6 L needed for quantification Prinn et al., Earth Syst. Sci. Data, 2018, 10, 985 Prinn et al., J. Geophys. Res., 2000, 105 (D14), 17751 https://agage.mit.edu/instruments/medusa-gas-chromatography-mass-spectrometry-medusa-gc-ms, last accessed: 17.12.2018 Christian Heusser und Franziska Jud 18.12.2018

GC-multidetector system and GC-MS GC-MD GC-MS (Medusa) Detection Electron Capture Detector (ECD) Flame Ionization Detector (FID) EI-quadrupole-MS Limit of detection 2.5 pg (GC-ECD) 1 pg (total ion current) 20 fg (single ion monitoring) Sample volume (air) 2 mL – 10 mL 2 L Median precision (1σ) 0.08 % (Barbados, 2017) 0.09 % (Ny Alesund, 2017) Analytes CFC-11, CFC-12, CFC-113, CH3CCl3, CCl4, N2O, CH4 (FID) Over 40 trace gases Measurement data for median precision: http://agage.eas.gatech.edu/data_archive/agage/ (last accessed: 16.12.2018) Prinn et al., Earth Syst. Sci. Data, 2018, 10, 985 Prinn et al., J. Geophys. Res., 2000, 105 (D14), 17751 S. Sousa and S. Bialkowski, Analytica Chimica Acta, 2001, 433, 181 Christian Heusser und Franziska Jud 18.12.2018

Remote sensing Measurements based on limb sounding Scan molecule specific IR emission lines Good vertical, but poor horizontal resolution Low concentrations measurable since atmospheric ray path is long Fischer et al., Atmos. Chem. Phys., 8, 2151–2188, 2008. Christian Heusser und Franziska Jud 18.12.2018

CFC-11 and East Asia Increasing emissions for CFC-11 since 2012 measured Faster releases from banks unlikely Illegal production in east Asia suspected Red lines: Northern hemisphere Blue lines: Southern hemisphere Grey lines: projections based on World Meteorological Organization scenarios Christian Heusser und Franziska Jud 18.12.2018

How to find the malefactor? Compare with measurement data from other AGAGE sites Sites closer to source will measure higher concentrations Additional measurements In country, close to factories On country borders, if measurements not allowed by country Satellite measurements Problem: no CFC-11 measuring satellite currently available Christian Heusser und Franziska Jud 18.12.2018

EIA report on illegal CFC-11 production in China Wide-spread illegal production, trade and use of CFC-11 in China 18 factories in east China listed that confirm using CFC-11 as blowing agent Large estimated number of unrecorded cases suspected EIA, Blowing It, 2018. Christian Heusser und Franziska Jud 18.12.2018

Situation in China Growing demand for affordable PU foam Bayer, BASF sell expensive foams CFC-11 popular as cheap and excellent blowing agent ~150 $/t cheaper than legal HCFC-141b No severe penalties for law-offending behavior Confiscation and fines up to 150‘000 $ Corrupt administration Production shut down when check is runned Various tricks to mask or hide use of CFC-11 EIA, Blowing It, 2018. Christian Heusser und Franziska Jud 18.12.2018

Comments on EIA report Measurements only indicate emission/use but not production of CFC-11 Origin unknown and not necessarily located in China Alternative sources for CFC-11 possible Illegal production of CFC-12 Leakage of old stockpiles Alan R. Katritzky et al.: Comprehensive Organic Functional Group Transformations. Elsevier, 1995. Christian Heusser und Franziska Jud 18.12.2018

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