Bibliographic record
Abstract
Since 1976, and more so since 1985, the Antarctic ozone level has suffered considerable depletion (termed as Antarctic ozone hole), attributed to the destructive effects of CFC compounds leaking into the atmosphere from man-made gadgets. The 12-month running means of South Pole Dobson ozone (monthly means, upto 1999 end only) were subjected to spectral analysis, which showed considerable, significant amplitudes for QBO (Quasi-biennial, 2-3 years) and QTO (Quasi-triennial, 3-4 years) oscillations, with a total range of 20-30 DU. When subtracted from the original values, a fairly smooth variation was seen, with a decrease from ~260 DU in 1986 to ~230 DU in 1996 (~12% decrease in 12-month running means), and an almost steady level thereafter. Thus, the net ozone variation at South Pole consists of two parts, (i) a long-term monotonically downward trend upto 1996 and a steady level thereafter and (ii) a superposed QBO-QTO oscillation. The chemical destruction effect is not likely to disappear soon, and may even increase if greenhouse effects, major volcanic eruptions or enhanced stratospheric cooling intervene. If the long-term level (i) remains steady, an extrapolation of the QBO-QTO patterns indicates that the ozone level is due for an increase from about 1999 end to about 2001 beginning. The purpose of the present analysis is to point out that, if such an increase of 20-30 DU occurs, it should not be misinterpreted as due to a decrease in chemical destruction, which scientists are eagerly awaiting due to the indication of a reduction in the halogen load in recent years due to adherence to the Montreal Protocol. After one or two years (in 2002), the extrapolated QBO-QTO oscillation may bring down the ozone level back again to the 1999 end level, and the apparent recovery may turn out to be a false signal.
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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) | 0.000 | 0.000 |
| Meta-epidemiology (broad) | 0.000 | 0.000 |
| Bibliometrics | 0.001 | 0.001 |
| Science and technology studies | 0.001 | 0.000 |
| Scholarly communication | 0.001 | 0.001 |
| Open science | 0.000 | 0.001 |
| Research integrity | 0.000 | 0.001 |
| Insufficient payload (model declined to judge) | 0.007 | 0.003 |
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".