Very short-lived halogens amplify recent and future ozone depletion trends in the tropical lower stratosphere.
Bibliographic record
Abstract
Recent observational evidences show ongoing net ozone depletion in the tropical lower stratosphere (LS) since the late 20th century, in contrast to the overall stratospheric ozone recovery following controls in the Montreal Protocol to limit the production of long-lived ozone depleting substances. Such behavior is currently thought to be driven by dynamical transport accelerated by global warming. In contrast, the role of chemistry, i.e., the enhanced ozone depletion due to emissions of halogenated ozone-depleting very short-lived substances (VSLS) has been considered to be unimportant. Here we employ a chemistry-climate model with a comprehensive chemical scheme to demonstrate that VSLS chemistry accounts for around a quarter of the observed tropical LS negative ozone trend in 1998-2018. We attribute such an effect to chemical reactions with VSLS from natural and anthropogenic emissions in concert. Future projections show the persistence of the currently unaccounted for contribution of VSLS to ozone loss throughout the 21st century in the tropical LS, the only region of the global stratosphere not projecting an ozone recovery by 2100. Our results show evidence for the need of mitigation strategies for regulating anthropogenic VSLS emissions to preserve the present and future ozone layer in low latitudes.
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 | 0.001 |
| Meta-epidemiology (narrow) | 0.000 | 0.000 |
| Meta-epidemiology (broad) | 0.000 | 0.000 |
| Bibliometrics | 0.000 | 0.000 |
| Science and technology studies | 0.000 | 0.000 |
| Scholarly communication | 0.001 | 0.001 |
| Open science | 0.000 | 0.001 |
| Research integrity | 0.000 | 0.000 |
| Insufficient payload (model declined to judge) | 0.002 | 0.000 |
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".