A Diurnal Cycle in the Energetics and Efficiencies of Tropical Cyclones
Bibliographic record
Abstract
Abstract The oceanic tropical cyclone (TC) diurnal cycle includes oscillations in the total rainfall and boundary layer inflow. A diurnal cycle may also occur in the TC energetics, including the wind field kinetic energy. The TC mechanical efficiency, a property of the TC bounded by the Carnot efficiency, depends on these energetics and so could experience a diurnal cycle. We use output from a hurricane nature run to investigate whether there is a diurnal cycle in the mechanical and Carnot efficiencies and energetics of TCs. Results from the nature run show some statistically significant indications of diurnal variability in the efficiencies and TC wind field kinetic energy but a lack of statistical significance for other energetics. We compare our results from the highly realistic simulation to two longer-lived, idealized simulated TCs using the Cloud Model 1, where the diurnal cycle can be isolated from environmental shear and forward motion. The first simulation is forced by the solar diurnal cycle, whereas the second is a control under perpetual-afternoon conditions. Results from the first simulation show statistically significant diurnal variability in several TC energetics and in the mechanical and Carnot efficiencies. Comparison to the control confirms that for most variables, this diurnal oscillation is not an artifact of the experimental setup. Finally, a comparison of the daily mean TC energetics and efficiencies between the two idealized simulations yields no statistically significant differences. This may indicate a lack of rectification of these variables by the diurnal cycle, although further ensemble studies should confirm this. Significance Statement The main purpose of this work is to examine the diurnal variability of the “mechanical efficiency” of tropical cyclones, which measures how well tropical cyclones convert the heating they experience into the strength of their winds. This matters because tropical cyclones are known to experience significant variability over the course of a day, which has important implications for tropical cyclone forecasting. However, the diurnal variability in the mechanical efficiency and related energetics has not received much attention. Our study could improve the forecasting of tropical cyclones by documenting another aspect of their 24-h variability. We find diurnal cycles in both the mechanical efficiency of tropical cyclones and in several related tropical cyclone energetics, such as the energy of the winds.
Fetched live from OpenAlex and de-inverted. Abstracts are not stored in this database: the inverted indexes are 8.6 GB of the frame’s 9.3 GB of text, and the host has 13 GB free.
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 | 0.001 |
| 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) | 0.001 | 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 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".