Technical Note: New ground-based FTIR measurements at Ile de La Réunion: observations, error analysis, and comparisons with independent data
Bibliographic record
Abstract
Abstract. Ground-based high spectral resolution Fourier-transform infrared (FTIR) solar absorption spectroscopy is a powerful remote sensing technique to obtain information on the total column abundances and on the vertical distribution of various constituents in the atmosphere. This work presents results from two short-term FTIR measurement campaigns in 2002 and 2004, held at the (sub)tropical site Ile de La Réunion (21°S, 55°E). These campaigns represent the first FTIR observations carried out at this site. The results include total column amounts from the surface up to 100 km of ozone (O3), methane (CH4), nitrous oxide (N2O), carbon monoxide (CO), ethane (C2H6), hydrogen chloride (HCl), hydrogen fluoride (HF) and nitric acid (HNO3), as well as some vertical profile information for the first four mentioned trace gases. The data are characterised in terms of the vertical information content and associated error budget. In the 2004 time series, the seasonal increase of the CO concentration was observed by the end of October, along with a sudden rise that has been attributed to biomass burning events in southern Africa and Madagascar. This attribution was based on trajectory modeling. In the same period, other biomass burning gases such as C2H6 also show an enhancement in their total column amounts which is highly correlated with the increase of the CO total columns. The observed total column values for CO are consistent with correlative data from MOPITT (Measurements Of Pollution In The Troposphere). Comparisons between our ground-based FTIR observations and space-borne observations from ACE-FTS (Atmospheric Chemistry Experiment – Fourier Transform Spectrometer) and HALOE (Halogen Occultation Experiment) confirm the feasibility of the FTIR measurements at Ile de La Réunion.
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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 | 0.002 | 0.003 |
| Meta-epidemiology (narrow) | 0.001 | 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 | 0.001 | 0.001 |
| Research integrity | 0.001 | 0.001 |
| Insufficient payload (model declined to judge) | 0.002 | 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".