Gravity Wave Breaking and Vortex Ring Formation Observed by PMC Turbo
Bibliographic record
Abstract
Abstract Polar mesospheric cloud (PMC) imaging and lidar profiling performed aboard the 5.9‐day PMC Turbo balloon flight from Sweden to northern Canada in July 2018 revealed a wide variety of gravity wave (GW) and instability events occurring nearly continuously at approximately 82 km. We describe one event exhibiting GW breaking and associated vortex rings driven by apparent convective instability. Using PMC Turbo imaging with spatial and temporal resolution of 20 m and 2 s, respectively, we quantify the GW horizontal wavelength, propagation direction, and apparent phase speed. We identify vortex rings with diameters of 2–5 km and horizontal spacing comparable to their size. Lidar data show GW vertical displacements of ±0.3 km. From the data, we find a GW intrinsic frequency and vertical wavelength of 0.009 ± 0.003 rad s −1 and 9 ± 4 km, respectively. We show that these values are consistent with the predictions of numerical simulations of idealized GW breaking. We estimate the momentum deposition rate per unit mass during this event to be 0.04 ± 0.02 m s −2 and show that this value is consistent with the observed GW. Comparison to simulation gives a mean energy dissipation rate for this event of 0.05–0.4 W kg −1 , which is consistent with other reported in situ measurements at the Arctic summer mesopause.
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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".