Ren et al. (2026) Evaluating the Collision‐Coalescence Process in Idealized Cloud Convection Using Large‐Eddy Simulations With Lagrangian Microphysics

⚠️ Warning: This summary was generated from the abstract only, as the full text was not available.

Identification

• Journal: Geophysical Research Letters
• Year: 2026
• Date: 2026-03-30
• Authors: Yangze Ren, Kamal Kant Chandrakar, Fan Yang, Raymond A. Shaw
• DOI: 10.1029/2025gl118873

Research Groups

Not explicitly stated in the abstract.

Short Summary

This paper employs large-eddy simulations with Lagrangian microphysics to evaluate the theoretical non-dimensional drizzle number (Dz) in a simulated convection-cloud chamber, confirming its utility in quantifying the impact of collisional growth on droplet size distribution and estimating collision rates.

Objective

• To evaluate the theoretical non-dimensional drizzle number (Dz) as a quantifier for the influence of collisional growth on droplet size distribution and for estimating collision rates in warm cloud precipitation.

Study Configuration

• Spatial Scale: Laboratory-scale (simulated tall convection-cloud chamber).
• Temporal Scale: Not explicitly stated, but relevant to the evolution of cloud droplets and drizzle initiation within the simulated chamber.

Methodology and Data

• Models used: Large-eddy simulations (LES) with Lagrangian microphysics.
• Data sources: Simulated data generated by the large-eddy simulations of a convection-cloud chamber.

Main Results

• A smaller drizzle number (Dz) correlates with a larger impact of collisions on the right tail of the droplet size distribution, which is consistent with theoretical predictions.
• The collision rate can be accurately estimated from the droplet size distribution by considering interactions only with cloud droplets of the same size at the mode radius.

Contributions

• Provides numerical validation for the theoretical non-dimensional drizzle number (Dz) using large-eddy simulations.
• Confirms the applicability of Dz for quantifying collisional growth and estimating collision rates in warm clouds.
• Suggests the idealized theory can be a valuable tool for designing cloud chambers for drizzle investigation and for improving the representation of drizzle formation in atmospheric models.

Funding

Not mentioned in the abstract.

Citation

@article{Ren2026Evaluating,
  author = {Ren, Yangze and Chandrakar, Kamal Kant and Yang, Fan and Shaw, Raymond A.},
  title = {Evaluating the Collision‐Coalescence Process in Idealized Cloud Convection Using Large‐Eddy Simulations With Lagrangian Microphysics},
  journal = {Geophysical Research Letters},
  year = {2026},
  doi = {10.1029/2025gl118873},
  url = {https://doi.org/10.1029/2025gl118873}
}