Sensitivity of cloud phase distribution to cloud microphysics and thermodynamics in simulated deep convective clouds and SEVIRI retrievals
Bibliographic record
Abstract
Abstract. The formation of ice in clouds is an important process in mixed-phase clouds, and the radiative properties and dynamical developments of clouds strongly depend on their partitioning between liquid and ice phases. In this study, we investigate the sensitivities of the cloud phase to ice-nucleating particle (INP) concentration and thermodynamics. Experiments are conducted using the ICOsahedral Nonhydrostatic model (ICON) at the convection-permitting resolution of about 1.2 km on a domain covering significant parts of central Europe, and are compared to two different retrieval products based on SEVIRI measurements. We select a day with several isolated deep convective clouds, reaching a homogeneous freezing temperature at the cloud top. The simulated cloud liquid pixel number fractions are found to decrease with increasing INP concentration both within clouds and at the cloud top. The decrease in cloud liquid pixel number fraction is not monotonic but is stronger in high INP cases. Cloud-top glaciation temperatures shift toward warmer temperatures with increasing INP concentration by as much as 8 °C. Moreover, the impact of INP concentration on cloud phase partitioning is more pronounced at the cloud top than within the cloud. Moreover, initial and lateral boundary temperature fields are perturbed with increasing and decreasing temperature increments from 0 to +/-3 K and +/-5 K between 3 and 12 km. Perturbing the initial thermodynamic state is also found to affect the cloud phase distribution systematically. However, the simulated cloud-top liquid number fraction, diagnosed using radiative transfer simulations as input to a satellite forward operator and two different satellite remote sensing retrieval algorithms, deviates from one of the satellite products regardless of perturbations in the INP concentration or the initial thermodynamic state for warmer sub-zero temperatures, while agreeing with the other retrieval scheme much better, in particular for the high INP and high convective available potential energy (CAPE) scenarios. Perturbing the initial thermodynamic state, which artificially increases the instability of the mid- and upper-troposphere, brings the simulated cloud-top liquid number fraction closer to the satellite observations, especially in the warmer mixed-phase temperature range.
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 | 0.001 | 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) | 0.000 | 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".