Lead Researchers: Irina Overeem (University of Colorado), Zoe Matthews (University of Southampton)

Modeling is the essential tool for understanding complex systems. Our vision for Delta-RADS (Risk Assessment and Decision Support) is to build a modeling system that:

  • Encapsulates the spatial/temporal dependencies of the bio-physical environment and social dynamics of a delta, 
  • Will be open access and runnable on personal computers, and
  • Will be credible to stakeholders and the decision making process.

We will start our modeling framework by building on the infrastructure of the Community Surface Dynamics Modeling System (CSDMS) e-modules, including the hydrological model TopoFlow, the river flux model HydroTrend, the coastline evolution model CEM, the delta deposition model Sedflux, and the regional ocean modeling system ROMS (http://csdms.colorado.edu/).  New components to be added include the distributed Water Balance and sediment transport (WBM and WBM-Sed) models, a storm surge model such as ADCIRC (http://adcirc.org/), and improved socio-economic understanding of deltas (http://www.espadelta.net/).  We will use the CSDMS services for easy user interaction through graphical user interfaces, model interoperability between different programming languages, protocols and low-level model coupling of models. The modeling system will be developed in open-source GIS format with linkages between Delta-DAT and RADS using the GRASS as a service component.

Modeling gaps that our team will investigate relate to the incompatibility between the scales at which data are available (from spatial average precipitation, to county level census data, to plot scale land use), scales at which processes operate (from micro-scale for biology to larger scale for sediment and land-ocean interactions), and model grid scale needed for computational efficiency; parameter estimation from limited data; and probabilistic modeling using ensembles for quantification of uncertainty; among others. 

Delta-RADS will integrate multiple scales and multiple thematic sectors of investigation that have usually been independently explored within their respective disciplines. This cross-sectorial approach will enable us to capture the effects of a dynamic range of drivers (climate, subsidence, demographic trends, economic development) on the natural, socio-economic and infrastructure resources of the delta. As such, it will evaluate trade-offs and guide governance and management responses in terms of ecosystem restoration, adaptation of land and water use, land reclamation, flood preparedness, wetland use, agricultural practices, to name a few.