Wang et al. (2026) Contrasting microphysics and environmental drivers of weak and intense convection-induced extreme precipitation: Insights from GPM DPR observations

Identification

• Journal: Atmospheric Research
• Year: 2026
• Date: 2026-01-09
• Authors: Zelin Wang, Xiong Hu, Weihua Ai, Shensen Hu, Junqi Qiao, X. B. Zhao
• DOI: 10.1016/j.atmosres.2026.108762

Research Groups

• College of Meteorology and Oceanography, National University of Defense Technology, Changsha, China
• College of Basic Education, National University of Defense Technology, Changsha, China

Short Summary

This study investigates the microphysical differences and environmental drivers of weak and intense convection-induced extreme precipitation events (EPEs) over South China using 10 years of GPM DPR observations, revealing distinct spatial distributions and microphysical mechanisms for each type of EPE.

Objective

• To identify and contrast the microphysical characteristics and environmental drivers of weak and intense convection-induced extreme precipitation events (WeEPEs and InEPEs) to improve the prediction of EPEs.

Study Configuration

• Spatial Scale: South China
• Temporal Scale: 10 years of observations

Methodology and Data

• Models used: Not explicitly used in this observational study.
• Data sources: Global Precipitation Measurement Dual-Frequency Precipitation Radar (GPM DPR) observations.

Main Results

• Most EPEs occur during morning and nighttime hours.
• WeEPEs are predominantly observed over land, while InEPEs are prevalent over the ocean, with their distribution regulated by ocean thermal gradients, moisture transport, and orographic lifting.
• Weak sea surface temperature (SST) gradients and southerly moisture transport generate offshore moisture centers, which contribute to the formation of oceanic WeEPEs.
• Strong SST gradients coupled with stronger southerly moisture transport form inland moisture centers, where orographic forcing enhances upward motion for strong convection (InEPEs).
• Weak convection generates extreme precipitation through a synergistic increase in particle size and concentration below the 0 °C level, with high concentration being more critical.
• For oceanic events below the 0 °C level: InEPEs show a slightly larger particle diameter increase (0.11 mm), whereas WeEPEs exhibit a much greater concentration increase (4.34 dB), leading to a larger reflectivity factor increase (7.58 dBZ).
• For the most extreme precipitation, both warm-rain and ice-phase processes play significant roles, even if one process dominates.
• Continental WeEPEs reach peak precipitation rates through ice-particle melting (16.1 mm/h) and warm-rain coalescence enhancing particle size (70.6 mm/h).
• Marine InEPEs (102.02 mm/h) rely on high liquid water path and efficient coalescence for maximum rates, with a warm-rain contribution of 43.3 mm/h.

Contributions

• Provides a comprehensive observational analysis contrasting the microphysical characteristics and environmental drivers of weak and intense convection-induced extreme precipitation events.
• Identifies distinct spatial distributions and regulatory mechanisms for WeEPEs (land-prevalent) and InEPEs (ocean-prevalent) in South China.
• Quantifies the relative importance of particle size and concentration increases in the microphysical processes leading to extreme precipitation from weak convection.
• Emphasizes the synergistic roles of both warm-rain and ice-phase processes in the most extreme precipitation events.

Funding

Not specified in the provided text.

Citation

@article{Wang2026Contrasting,
  author = {Wang, Zelin and Hu, Xiong and Ai, Weihua and Hu, Shensen and Qiao, Junqi and Zhao, X. B.},
  title = {Contrasting microphysics and environmental drivers of weak and intense convection-induced extreme precipitation: Insights from GPM DPR observations},
  journal = {Atmospheric Research},
  year = {2026},
  doi = {10.1016/j.atmosres.2026.108762},
  url = {https://doi.org/10.1016/j.atmosres.2026.108762}
}