Towards the development of a high-resolution historical flood inundation reanalysis dataset for the conterminous United States
Abstract
A high-resolution historical flood inundation dataset that covers the entire conterminous United States (CONUS) can serve as a valuable tool to understand region-specific flood risks and devise long-term flood mitigation and resilience strategies. The accurate representation of flood dynamics at a large scale requires the solution of full 2D shallow water equations while using a spatial resolution that is locally relevant. In this study, we introduce a CONUS-wide implementation of a GPU accelerated 2D hydrodynamic model - TRITON (https://triton.ornl.gov/) to reconstruct major historic flood events. Driven by 2002-2018 National Center for Environmental Prediction Stage IV Hourly Quantitative Precipitation Estimates, historic runoff and streamflow were simulated by a calibrated VIC-RAPID hydrologic modeling framework for all HUC04 subregions across the CONUS which serve as input to TRITON. TRITON inundation model is then setup using 10m National Elevation Dataset for the baseline terrain information. The default TRITON implementation is driven by long-term climatic mean runoff and streamflow to obtain steady-state channel flow conditions which serve as initial water depths and velocity information for event-based TRITON simulation. The performance of simulated flood inundation maps is evaluated using various temporally static benchmark information, including high-water marks, and remote sensing derived inundation maps. The temporal evolution of flood simulations is evaluated using US Geological Survey stage data. Finally, we discuss the challenges and barriers in national-continental scale high-resolution inundation modeling, calibration and validation, future developments targeted to improve the representation of flood regimes, and implications for real-time flood forecasting.
- Publication:
-
AGU Fall Meeting Abstracts
- Pub Date:
- December 2022
- Bibcode:
- 2022AGUFM.H34F..04G