Study of mesosphere lower thermosphere (MLT) mean winds over Yamagawa (31.2°N, 130.6°E) during 1996–1998
Bibliographic record
Abstract
The mean motions in the mesosphere and lower thermosphere from 70 to 98 km were observed with the recently installed MF radar at Yamagawa (31.2°N, 130.6°E). We have utilized the continuous wind data collected during the 3‐year period 1996–1998. Seasonal variations of mean winds over the site are constructed and the climatologies are then compared with observations from similar latitudes and the latest empirical model results. The mean zonal circulation in the mesosphere is characterized by a clear annual variation with summer westward (easterly) flow and winter eastward (westerly) flow. The summer westward jet closes at a height in between 80 and 85 km. Southward motion exhibits its dominance at 90–98 km during all times of the year, and at lower heights (70–90 km), southward/northward motions predominate during summer/winter season. The annual mean zonal wind has an eastward motion in the 70–98 km. It maximizes at around 90 km with a strength of 15–17 m/s. The annual mean meridional circulation shows both poleward and equatorward motions. Harmonic analysis of mean zonal winds clearly demonstrates the dominance of annual oscillation over the other periods. Comparison of mean winds over Yamagawa, Japan, and London, Ontario, Canada, demonstrates that the zonal circulation over these two sites has some similar features. Similarly, the results compared for Yamagawa and Urbana show some consistency in mean wind circulation. The paper also presents the results of the comparison of MF radar‐derived winds and the HWM93 model outputs. There is reasonable agreement between the observation and the model 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 | 0.000 |
| 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 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".