Sun et al. (2025) Complex networks reveal teleconnections across cascading floods in the Yangtze River Basin

Identification

• Journal: Natural Hazards
• Year: 2025
• Date: 2025-09-05
• Authors: Fengyun Sun, Alfonso Mejía, Sanjib Sharma, Peng Zeng, Yi’na Hu, Kai Yang, Yue Che
• DOI: 10.1007/s11069-025-07635-z

Research Groups

• School of Environmental and Geographical Sciences, Shanghai Normal University, Shanghai, China
• Shanghai Yangtze River Delta Urban Wetland Ecosystem National Field Observation and Research Station, Shanghai, China
• Department of Civil and Environmental Engineering, The Pennsylvania State University, University Park, PA, USA
• Department of Civil and Environmental Engineering, Howard University, Washington D.C., USA
• School of Ecological and Environmental Sciences, East China Normal University, Shanghai, China

Short Summary

This study applies complex network analysis to investigate the teleconnection patterns and synchronization characteristics of cascading floods across 125 subbasins in the Yangtze River Basin (YRB) from 1961 to 2020, revealing that streamflow-related networks exhibit stronger connectivity and identifying a significant large-scale propagation mechanism where downstream water yield regulates upstream precipitation.

Objective

• To investigate flood propagation and synchronization dynamics across 125 subbasins in the Yangtze River Basin (YRB) to understand the poorly understood teleconnection patterns and synchronization characteristics of cascading floods.

Study Configuration

• Spatial Scale: Yangtze River Basin (YRB), encompassing 125 subbasins.
• Temporal Scale: 60 years, from 1961 to 2020.

Methodology and Data

• Models used: Complex network analysis (for investigating flood propagation and synchronization dynamics).
• Data sources: Three hydrological variables: precipitation (P), water yield (Y), and streamflow (S).

Main Results

• Streamflow-related networks (P–S, Y–S, and S–S) demonstrate stronger connectivity, characterized by more links, greater stream order differences, longer total propagation distances, fewer isolated subbasins, and larger cluster sizes, compared to precipitation- and water yield-related networks.
• Precipitation-related networks (P–P, P–Y, and P–S) reflect the influence of large-scale atmospheric processes, indicated by longer individual links.
• The water yield-dominated network (Y–Y) exhibits the fewest links, likely due to the constraining effect of local factors on propagation.
• A significant large-scale propagation mechanism is identified where downstream water yield regulates upstream precipitation in the YRB, suggesting the potential role of hydrological feedbacks in flood dynamics.
• Spatial patterns of cascading floods highlight certain subbasins as critical flood propagators and hubs.

Contributions

• Presents a novel framework for understanding cascading floods within complex hydroclimatic systems.
• Underscores the importance of hydrological feedbacks in shaping flood dynamics.
• Provides valuable information for developing flood management strategies at both local and regional scales.

Funding

• National Science Foundation for Young Scientists of China (Grant No. 42007417)
• Program of the Science and Technology Commission of Shanghai Municipality (Grant No. 23002400400)
• National Science Foundation for Young Scientists of China (Grant No. 42201102)

Citation

@article{Sun2025Complex,
  author = {Sun, Fengyun and Mejía, Alfonso and Sharma, Sanjib and Zeng, Peng and Hu, Yi’na and Yang, Kai and Che, Yue},
  title = {Complex networks reveal teleconnections across cascading floods in the Yangtze River Basin},
  journal = {Natural Hazards},
  year = {2025},
  doi = {10.1007/s11069-025-07635-z},
  url = {https://doi.org/10.1007/s11069-025-07635-z}
}