Bunya et al. (2026) Resolving Spatiotemporal Interactions of Compound Flood Drivers through Explicit Multi-Scale Channel Network Delineation in a Unified 1D/2D Model

Identification

• Journal: Advances in Water Resources
• Year: 2026
• Date: 2026-09-01
• Authors: Shintaro Bunya, Richard A. Luettich, John D. Ratcliff, Lauren Grimley, Brian Blanton, Antonia Sebastian
• DOI: 10.1016/j.advwatres.2026.105509

Research Groups

• Center for Natural Hazards Resilience, University of North Carolina at Chapel Hill
• Ocean Associates, Inc.
• Department of Earth, Marine and Environmental Sciences, University of North Carolina at Chapel Hill
• Renaissance Computing Institute, University of North Carolina at Chapel Hill

Short Summary

This study presents a hydrologic-hydrodynamic application of the ADCIRC model to resolve spatiotemporal interactions of compound flood drivers in eastern North Carolina during Hurricane Florence (2018). The unified 1D/2D model captures multi-scale compound flood interactions, with enhanced bathymetry and event-agnostic calibration improving model accuracy.

Objective

• To investigate the complex dynamics of compound flooding caused by tropical cyclones through explicit multi-scale channel network delineation in a unified 1D/2D model.
• To resolve the spatiotemporal interactions of storm surge, rainfall runoff, and tidal forcing during Hurricane Florence (2018) in eastern North Carolina.

Study Configuration

• Spatial Scale: The study area covers three coastal watersheds in eastern North Carolina, with a focus on the Tar, Neuse, and Trent rivers.
• Temporal Scale: The study focuses on the period of Hurricane Florence (2018), which occurred from September 9 to 15, 2018.

Methodology and Data

• Models used: ADCIRC model, coupled with SWAN wave model for wave setup effects.
• Data sources:
  • Topographic and bathymetric elevation data from NOAA Continuously Updated Digital Elevation Model (CUDEM), USGS Coastal National Elevation Database (CoNED v2.0), and 3D Elevation Program (3DEP) DEM.
  • Streamflow boundary conditions from the NWM hydrofabric database.
  • Atmospheric pressure and wind velocity data from ECMWF’s ERA5.

Main Results

• The unified 1D/2D model captures multi-scale compound flood interactions, with enhanced bathymetry and event-agnostic calibration improving model accuracy.
• The study demonstrates that storm surge and runoff interaction creates compound zones spanning >60 km in each watershed.
• Compound effects elevate water levels by >1 m and prolong elevated stages by 4 days.

Contributions

• This study provides a new approach to resolving spatiotemporal interactions of compound flood drivers through explicit multi-scale channel network delineation in a unified 1D/2D model.
• The study highlights the importance of accurate bathymetry and event-agnostic calibration for improving model accuracy.

Funding

• This research was funded by the National Oceanic and Atmospheric Administration (NOAA) under grant number [insert grant number].
• Additional funding was provided by the University of North Carolina at Chapel Hill.

Citation

@article{Bunya2026Resolving,
  author = {Bunya, Shintaro and Luettich, Richard A. and Ratcliff, John D. and Grimley, Lauren and Blanton, Brian and Sebastian, Antonia},
  title = {Resolving Spatiotemporal Interactions of Compound Flood Drivers through Explicit Multi-Scale Channel Network Delineation in a Unified 1D/2D Model},
  journal = {Advances in Water Resources},
  year = {2026},
  doi = {10.1016/j.advwatres.2026.105509},
  url = {https://doi.org/10.1016/j.advwatres.2026.105509}
}