Inferring Lifetimes, Banks and Unexpected Emissions of CFC-11, 12 and 113
Abstract
Chlorofluorocarbons (CFCs) are harmful ozone depleting substances and greenhouse gases. CFC production was phased-out under the Montreal Protocol, however recent studies suggest new and unexpected emissions of CFC-11. Quantifying CFC emissions requires accurate estimates of both atmospheric lifetimes and ongoing emissions from old equipment (i.e. `banks'). In a Bayesian framework we simultaneously infer lifetimes, banks and emissions of CFC-11, 12 and 113 using a wide range of constraints. We find that lifetimes of all three gases are shorter than previous estimates, based on similar techniques, suggesting that inferred emissions are likely higher than recent studies suggest. Our analysis indicates that bank emissions are decreasing faster than inferred emissions, and we estimate non-bank emissions during 2014-2016 were 19.6, 16.2, and 7.7 Gg/yr for CFC-11, 12 and 113, respectively. While recent studies have focused on unexpected CFC-11 emissions, our results call for further investigation of unexpected emissions of CFC-12 and 113.
- Publication:
-
AGU Fall Meeting Abstracts
- Pub Date:
- December 2020
- Bibcode:
- 2020AGUFMU002...04L
- Keywords:
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- 0810 Post-secondary education;
- EDUCATION;
- 0815 Informal education;
- EDUCATION