Brightness variations of the northern 630nm intertropical arc and the midnight pressure bulge over Eritrea
Bibliographic record
Abstract
Abstract. The nightglow brightness at 630nm from the thermospheric O(1D) layer was monitored nightly at Asmara, Eritrea (15.4° N, 39.9° E, 7° N dip) with an all-sky imager. Averages of north-south strips of the images enabled contour plots of brightness on a latitude vs. local time grid. The contours show the movement of the intertropical arc southward before midnight, staying just north of Asmara after midnight, and gradually brightening to a maximum at 02:00h local civil time, 02:00 LT, after which it disappears before dawn. It is argued that all features of the plots can be explained by known mechanisms capable of driving ions along magnetic field lines, including the fountain effect, summer to winter transequatorial winds, and the midnight pressure bulge. The 02:00 LT brightness maximum is the most striking and the most persistent feature in the data. The persistence of the location of the 02:00 LT brightening is attributed to a pressure bulge centered on the geographic equator at midnight and extending to higher latitudes with increasing local time in both the winter and the summer hemispheres. The bulge is shown to be stronger near solstice than near equinox, confirming earlier work.
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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 | 0.000 | 0.000 |
| 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 | 0.000 | 0.000 |
| Open science | 0.000 | 0.000 |
| Research integrity | 0.000 | 0.000 |
| Insufficient payload (model declined to judge) | 0.000 | 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".