Global emissions of five controlled CFCs have increased since 2
Bibliographic record
Abstract
Production and consumption of ozone-depleting chlorofluorocarbons (CFCs) are controlled under the Montreal Protocol. CFC production for most applications was banned globally in 2010, albeit with exemptions for uses assumed to cause negligible emissions to the atmosphere, such as in the production of other chemicals. A few years ago, emissions of CFC-11 were reported to be increasing after their phase-out, most likely due to unreported production and non-compliance, which sparked widespread, renewed attention to this topic. Here we show that emissions of five other CFCs have increased since 2010, namely CFC-13, CFC-112a, CFC-113a, CFC-114a and CFC-115. Three of these CFCs are likely increasing due to their involvement in the production of non-ozone-depleting HFCs, which have largely replaced CFCs and HCFCs in many applications. The drivers behind the increase in the other two CFCs is unclear. While the impact of these CFCs on ozone layer recovery will likely be small, these long-lived CFCs are potent greenhouse gases and their CO2-equivalent emissions in 2020 were comparable to those of a mid-sized European country.
Fetched live from OpenAlex and de-inverted. Abstracts are not stored in this database: the inverted indexes are 8.6 GB of the frame’s 9.3 GB of text, and the host has 13 GB free.
How this classification was reachedexpand
Full frame machine prediction
Teacher imitationNot calibrated prevalence, not ground truth. Human validation pending. The Gemma side is a direct model label for every work in the frame, read from the title-only record. The Codex side is a classifier learned from the 10,348 direct Codex labels and calibrated to design-weighted sample rates; fields without enough sample support carry no Codex call. Candidate is the union of the two sides; consensus is their intersection. These outputs are machine_predicted_unvalidated and are not human labels.
Distilled classifier scores by category (both heads)
| Category | Codex | Gemma |
|---|---|---|
| Metaresearch | 0.000 | 0.000 |
| Meta-epidemiology (narrow) | 0.001 | 0.000 |
| Meta-epidemiology (broad) | 0.000 | 0.001 |
| Bibliometrics | 0.001 | 0.002 |
| Science and technology studies | 0.001 | 0.000 |
| Scholarly communication | 0.001 | 0.001 |
| Open science | 0.000 | 0.001 |
| Research integrity | 0.001 | 0.001 |
| Insufficient payload (model declined to judge) | 0.008 | 0.001 |
Machine scores (provisional)
The two teacher heads of the student model, read on this work. A score orders the frame for review; it never asserts a category, and the validation status ships verbatim with every row.
Baseline scores from an immature model (maturity gate not passed, 7 training rounds). Scores rank; they never assert a category.
score_only:v0-immature-baseline · verbatim from the scoring run: score_only means the number may rank works, and no category label ships from itClassification
machine, unvalidatedMachine predicted; a candidate call from one source (direct Gemma or distilled Codex), not a consensus.
How this classification was reached, model by model and score by score, is at the end of the page under "How this classification was reached".