Optical Spectrograph and Infra‐Red Imaging System (OSIRIS) observations of mesospheric OH A<sup>2</sup>Σ<sup>+</sup>‐X<sup>2</sup>Π 0‐0 and 1‐1 band resonance emissions
Bibliographic record
Abstract
Although only a minor species, the OH molecule plays an important role in the photochemical control of mesospheric ozone density and has been the target of a number of observational programs, principally through the OH A 2 Σ + ‐X 2 Π 0‐0 band emission at 308 nm. This emission band arises from solar resonance fluorescence excitation of OH X 2 Π ground state molecules, and its observation is complicated by the presence of an underlying atmospheric Rayleigh scattering spectrum. We show that the OH A 2 Σ + ‐X 2 Π 0‐0 band emission has been reliably and routinely detected with the moderately low, 0.9 nm, spectral resolution Optical Spectrograph and Infra‐Red Imaging System (OSIRIS) limb scanning spectrograph. Changes in upper mesospheric water vapor observed by the Halogen Occultation Experiment (HALOE) are readily detected as changes in the OH density profiles seen by OSIRIS. Altitude profiles of OH density in the middle and upper mesosphere are in good agreement with model results that incorporate coordinated HALOE water vapor measurements. The agreement is within the HALOE and OSIRIS error limits when the recommended standard reaction rates are assumed. Conversely, model calculations of OH density using the revised reaction rates proposed to explain the Middle Atmosphere High‐Resolution Spectrograph Investigation (MAHRSI) OH profiles typically fall outside the observed OSIRIS error limits. The OSIRIS results suggest that the probable difference between the observed and modeled OH densities is less than 15% from 55 to 80 km. Diurnal and seasonal OH variations observed by OSIRIS are in good agreement with model predictions. These successful comparisons suggest that the OSIRIS OH database, spanning more than 4 years of operation and broad ranges of latitude and local time, can contribute significantly to studies of OH photochemistry and upper mesospheric water vapor.
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How this classification was reachedexpand
Full frame distilled prediction
Teacher imitationNot calibrated prevalence, not ground truth. Human validation pending. Learned from the 10,348 direct Codex labels and 10,348 direct Gemma labels. Candidate is the union of thresholded teacher heads; consensus is their intersection. These outputs are machine_predicted_unvalidated and are not human labels or direct frontier model labels.
Codex and Gemma teacher scores by category
| Category | Codex | Gemma |
|---|---|---|
| Metaresearch | 0.002 | 0.001 |
| Meta-epidemiology (narrow) | 0.001 | 0.000 |
| Meta-epidemiology (broad) | 0.001 | 0.000 |
| Bibliometrics | 0.000 | 0.002 |
| Science and technology studies | 0.001 | 0.001 |
| Scholarly communication | 0.000 | 0.001 |
| Open science | 0.001 | 0.000 |
| Research integrity | 0.000 | 0.002 |
| 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 teacher head, 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".