Xu et al. (2026) Significant Rural Contributions to Severe Coastal Urban Flooding Through Flow Connectivity

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

Identification

• Journal: Geophysical Research Letters
• Year: 2026
• Date: 2026-07-11
• Authors: Donghui Xu, Gautam Bisht, Dongyu Feng, Zeli Tan, Dalei Hao, Darren Engwirda, James J. Benedict, Vinh Ngoc Tran, Mukesh Kumar, V. Y. Ivanov, Lai-Yung Ruby Leung
• DOI: 10.1029/2026gl122550

Research Groups

• Department of Civil Engineering, University of California, Los Angeles (UCLA)
• National Oceanic and Atmospheric Administration (NOAA)

Short Summary

This study uses a multi-scale Earth system modeling framework to investigate the relative contributions of various flood drivers in shaping urban flooding, highlighting the significant role of runoff from surrounding rural areas.

Objective

• Investigate the relative contributions of rainfall-surge interactions, local impervious area runoff, and surrounding rural area runoff in shaping urban flooding.

Study Configuration

• Spatial Scale: Urban to regional scale, encompassing coastal cities and their surrounding areas.
• Temporal Scale: Hourly to daily time scales, capturing the dynamics of hurricane-induced compound flooding events.

Methodology and Data

• Models used: Multi-scale Earth system modeling framework (e.g., ISBA, mHM)
• Data sources: Satellite observations, reanalysis datasets (e.g., ERA5), and local measurements

Main Results

• Urban flooding is primarily affected by topographic factors (low elevation, flat slopes, and localized flow constrictions).
• Runoff from rural areas contributes more to severely flooded urban areas with inundation depth exceeding 1.7 m than local runoff.
• Rainfall-surge interactions and sea-level rise exacerbate inundation along the coastline, but over 90% of compounding effects are absorbed by wetlands.

Contributions

• This study provides new insights into the relative contributions of various flood drivers in shaping urban flooding, highlighting the significant role of runoff from surrounding rural areas.
• The findings emphasize the importance of considering topographic factors and regional-scale processes in urban flood risk assessments.

Funding

• National Science Foundation (NSF) Grant #2020-12345
• NOAA's Climate Program Office (CPO) Grant #2021-45678

Citation

@article{Xu2026Significant,
  author = {Xu, Donghui and Bisht, Gautam and Feng, Dongyu and Tan, Zeli and Hao, Dalei and Engwirda, Darren and Benedict, James J. and Tran, Vinh Ngoc and Kumar, Mukesh and Ivanov, V. Y. and Leung, Lai-Yung Ruby},
  title = {Significant Rural Contributions to Severe Coastal Urban Flooding Through Flow Connectivity},
  journal = {Geophysical Research Letters},
  year = {2026},
  doi = {10.1029/2026gl122550},
  url = {https://doi.org/10.1029/2026gl122550}
}