Yang et al. (2026) Improvement of riming process parameterization in the WRF model and its advantages in simulating precipitation over the Tibetan Plateau

Identification

• Journal: npj Climate and Atmospheric Science
• Year: 2026
• Date: 2026-08-20
• Authors: Kunjing Yang, Xiaoqi Xu, Chunsong Lu, Jinghua Chen, Jing Yang, Junjun Li, Kai Yang, Naifu Shao, Jian Li, Xingwen Jiang, Haoming Chen
• DOI: 10.1038/s41612-026-01510-9

Research Groups

• China Meteorological Administration Aerosol-Cloud and Precipitation Key Laboratory
• Collaborative Innovation Center on Forecast and Evaluation of Meteorological Disasters (CIC-FEMD), Ministry of Education, Nanjing University of Information Science and Technology
• Jiangsu Key Laboratory of Severe Storm Disaster Risk/Key Laboratory of Transportation Meteorology of CMA, Nanjing Innovation Institute for Atmospheric Sciences, Chinese Academy of Meteorological Sciences-Jiangsu Meteorological Service
• National Institute of Education (NIE), Nanyang Technological University (NTU), Singapore
• Tianjin Climate Center, Tianjin
• State Key Laboratory of Severe Weather, Chinese Academy of Meteorological Sciences, Beijing
• Institute of Tibetan Plateau Meteorology, China Meteorological Administration, Beijing
• Heavy Rain and Drought-Flood Disasters in Plateau and Basin Key Laboratory of Sichuan Province, Institute of Tibetan Plateau Meteorology, China Meteorological Adminstration, Chengdu
• State Key Laboratory of Severe Weather Meteorological Science and Technology, Chinese Academy of Meteorological Sciences, Beijing

Short Summary

This study improves the riming parameterization within the WRF Morrison scheme by adopting constant reduction coefficients and introducing a diagnostic mixing homogeneity parameter χ for snow and graupel. The modified scheme shows superior performance in simulating precipitation over the Tibetan Plateau.

Objective

• To improve the accuracy of precipitation simulation over the Tibetan Plateau by optimizing the riming process parameterization

Study Configuration

• Spatial Scale: Regional scale, focusing on the Tibetan Plateau
• Temporal Scale: Hourly to monthly time scales, with a focus on the 72-h accumulated precipitation distribution

Methodology and Data

• Models used: WRF v4.2.2 model
• Data sources: IMERG precipitation product, satellite data, observation data

Main Results

• The modified scheme shows superior performance in simulating precipitation over the Tibetan Plateau, with a 23.8% reduction in RMSE compared to the Default experiment.
• The dynamic regulation of riming rates based on temperature and water content is found to be crucial for improving precipitation simulation.

Contributions

• This study provides a physically realistic simulation of microphysical evolution by introducing a diagnostic mixing homogeneity parameter χ for snow and graupel.
• The modified scheme shows superior performance in simulating the spatial distribution and location of convective precipitation events over the TP.

Funding

• China Meteorological Administration Aerosol-Cloud and Precipitation Key Laboratory
• Collaborative Innovation Center on Forecast and Evaluation of Meteorological Disasters (CIC-FEMD), Ministry of Education, Nanjing University of Information Science and Technology

Citation

@article{Yang2026Improvement,
  author = {Yang, Kunjing and Xu, Xiaoqi and Lu, Chunsong and Chen, Jinghua and Yang, Jing and Li, Junjun and Yang, Kai and Shao, Naifu and Li, Jian and Jiang, Xingwen and Chen, Haoming},
  title = {Improvement of riming process parameterization in the WRF model and its advantages in simulating precipitation over the Tibetan Plateau},
  journal = {npj Climate and Atmospheric Science},
  year = {2026},
  doi = {10.1038/s41612-026-01510-9},
  url = {https://doi.org/10.1038/s41612-026-01510-9}
}