Liu et al. (2026) Deciphering divergent atmospheric river environments in extreme and non-extreme precipitation over the lower reach of Yangtze River Basin

Identification

• Journal: Atmospheric Research
• Year: 2026
• Date: 2026-03-24
• Authors: Xiaofei Liu, Bin Chen, Wei Zhang, Wang ChunZhu, Yeran Yu, Xiangde Xu
• DOI: 10.1016/j.atmosres.2026.108960

Research Groups

• State Key Laboratory of Severe Weather Meteorological Science and Technology (LaSW), Chinese Academy of Meteorological Sciences (CAMS), Beijing, China
• Utah State University, Logan, UT, USA
• China Meteorological Administration Training Centre, Beijing, China

Short Summary

This study investigates the distinct atmospheric environments of atmospheric rivers (ARs) that lead to extreme precipitation (EP) versus those that do not, focusing on the lower Yangtze River Basin (LYRB) over 32 summer seasons. It reveals that AR&EP events are characterized by enhanced moisture from mid-to-high latitudes, specific large-scale circulation anomalies, and the crucial role of the Mei-yu front, providing key insights for improved forecasting.

Objective

• To distinguish the atmospheric environments of atmospheric rivers (ARs) that lead to extreme precipitation (AR&EP) from those that do not (AR&NONEP) in the lower Yangtze River Basin (LYRB).

Study Configuration

• Spatial Scale: Lower Yangtze River Basin (LYRB)
• Temporal Scale: 32 years of summer seasons

Methodology and Data

• Models used: Not explicitly mentioned. The study focuses on comparing observed or reanalysis-derived atmospheric environments.
• Data sources: Not explicitly mentioned, but likely involves reanalysis products for large-scale circulation anomalies and observational data for precipitation and convective activity over the specified temporal and spatial scales.

Main Results

• While moisture sources are spatially similar for both AR&EP and AR&NONEP events, AR&EP events exhibit enhanced moisture originating from regions west and north of the LYRB, indicating a greater dependence on excess moisture from mid- to high-latitudes.
• Key large-scale circulation anomalies identified during AR&EP events include a strengthened and westward-extended western North Pacific subtropical high, an enhanced westerly jet, an intensified and eastward-extended South Asian high, and a deepened upper-level trough.
• The deep East Asian Trough (EAT) and strengthened westerly jets are identified as the primary factors differentiating AR&EP from AR&NONEP events.
• Significant local differences in convective activity were observed, underscoring the essential role of the Mei-yu front in triggering AR&EP.
• The synergy among the deepened upper-level trough, moisture availability, and localized uplift provided by the Mei-yu front is crucial for accurately predicting AR&EP in the LYRB region.

Contributions

• Provides a comprehensive comparison of the atmospheric environments associated with ARs that do and do not produce extreme precipitation in the lower Yangtze River Basin.
• Identifies specific large-scale circulation patterns (e.g., deep EAT, strengthened westerly jet) and enhanced mid-to-high latitude moisture sources as key differentiators for AR&EP events.
• Highlights the critical local role of the Mei-yu front and convective activity in triggering AR-induced extreme precipitation in the region.
• Offers valuable insights for improving the predictive capabilities of extreme precipitation events associated with atmospheric rivers in East Asia.

Funding

• Not mentioned in the provided text.

Citation

@article{Liu2026Deciphering,
  author = {Liu, Xiaofei and Chen, Bin and Zhang, Wei and ChunZhu, Wang and Yu, Yeran and Xu, Xiangde},
  title = {Deciphering divergent atmospheric river environments in extreme and non-extreme precipitation over the lower reach of Yangtze River Basin},
  journal = {Atmospheric Research},
  year = {2026},
  doi = {10.1016/j.atmosres.2026.108960},
  url = {https://doi.org/10.1016/j.atmosres.2026.108960}
}