2019 CSDMS meeting-082
Introducing a sediment module to the National Water Model (WRF-Hydro)
The Weather Research and Forecasting Model Hydrological modeling system (WRF-Hydro) is an open-source community model and has been used for a range of projects, including flash flood prediction, regional hydroclimate impacts assessment, seasonal forecasting of water resources, and land-atmosphere coupling studies. We modified the CASCade 2 Dimensional SEDiment (CASC2D-SED) model and adapted it to the WRF-Hydro platform. The model mainly contains two components: (1) sediment erosion and transport from overland to channel, and (2) sediment transport through the channel to the watershed outlet. Based on USLE formula, sediment is eroded by overland flow with consideration of soil type, vegetation type as well as bed slope. Following through the direction of steepest slope, the eroded sediment is transported grid by grid all the way to the channel, meanwhile deposition process is parameterized by sediment’s settling velocity, time step and water depth. Once sediment gets into channel, it will be carried by the stream flow to the watershed outlet. To test its robustness, we adapted WRF-Hydro sediment model to the watershed of Goodwin Creek, Mississippi, USA. A preliminary model-data comparison indicates our model is capable of reproduce water and sediment discharge during a storm event.