Western European emission estimates of CFC-11, CFC-12 and CCl₄ derived from atmospheric measurements from 2008 to 2021

Abstract. Production and consumption of CFC-11 (trichlorofluoromethane, CCl3F), CFC-12 (dichlorodifluoromethane, CCl2F2) CCl4 (carbon tetrachloride) are controlled under the regulations Montreal Protocol have been phased out globally since 2010. Only is still widely produced as a chemical feedstock. After 2010, emissions should therefore mostly originate from existing banks (e.g. foams, mobile air conditioning units refrigerators); however evidence has emerged an increase in global last decade, some which not fully accounted for. The motivation for this work was to assess CFC-11, western Europe. All countries region subject controls late 1980s and, non-Article 5 Parties, prohibited producing CFCs dispersive use 1996. Four different inverse modelling systems used estimate these gases 2008 2021 using data four atmospheric measurement stations: Mace Head (Ireland), Jungfraujoch (Switzerland), Monte Cimone (Italy) Tacolneston (UK). average model studies found that European between were declining at 3.5 % yr−1 (2.7 yr−1–4.8 yr−1), 7.7 (6.3 yr−1–8.0 yr−1) 4.4 (2.6 yr−1–6.4 respectively. Even though throughout period, area including northern France, Belgium, Netherlands Luxembourg showed consistently elevated compared with surrounding regions. Emissions slightly same region. highest south France. France had all three over period 2008–2021. Europe (2008–2021) on 2.4 ± 0.4 Gg (CFC-11), 1.3 0.3 (CFC-12) 0.9 0.2 (CCl4). Our estimated decline consistent bank release rate 3.4 %–4.5 %). This study concludes declined Therefore, no contributed unexplained part concentrations observed decade.