Estimation of stratospheric age spectrum from chemical tracers
Bibliographic record
Abstract
We have developed a technique to diagnose the stratospheric age spectrum and estimate the mean age of air using the distributions of at least four constituents with different photochemical lifetimes. We demonstrate the technique using a 3‐D CTM and then apply the technique to OMS tropical balloon observations, UARS CLAES January 1993, and ACE February–March 2005 observations of CFC11, CFC12, CH4, and N2O. Our results using the ACE and OMS data are generally in agreement with mean age of air estimates from the chemical model and from observations of SF6 and CO2; however, the UARS‐derived mean age estimates show an intrusion of very young tropical air into the midlatitude stratosphere. The UARS CLAES values of F11 and F12 appear to be significantly higher than ACE and model values and bias our lower‐stratospheric estimates of the age derived from UARS data toward younger values.
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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 | 0.001 |
| Meta-epidemiology (narrow) | 0.000 | 0.000 |
| Meta-epidemiology (broad) | 0.000 | 0.000 |
| Bibliometrics | 0.001 | 0.000 |
| Science and technology studies | 0.000 | 0.000 |
| Scholarly communication | 0.000 | 0.000 |
| Open science | 0.000 | 0.000 |
| Research integrity | 0.000 | 0.000 |
| Insufficient payload (model declined to judge) | 0.001 | 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".