CSDMS 2022: Environmental Extremes and Earthscape Evolution

Variable resolution mesh based flow direction and hydrologic modeling: An introduction to HexWatershed

Chang Liao

Pacific Northwest National Laboratory, United States
Tian Zhou Pacific Northwest National Laboratory United States

Flow routing map is the cornerstone of spatially distributed hydrologic models. In this clinic we will introduce HexWatershed, a scale-free, mesh independent flow direction model. It supports DOE’s Energy Exascale Earth System Model (E3SM) to generate hydrologic parameters and river network representations on both structured and unstructured meshes. In this presentation, we will overview the capabilities of HexWatershed with an emphasis on river network representation and flow direction modeling. We will also provide participants with the tools to begin their own research with hydrologic model workflows. Through hands-on tutorials and demonstrations, participants will gain some insights into the relationship between meshes and flow direction, and how HexWatershed handles river network in various meshes. We will also demonstrate how to use the HexWatershed model outputs in the large-scale hydrologic model, Model for Scale Adaptive River Transport (MOSART). Participants will be provided with additional resources that can be used to extend the tutorial problems and gain additional familiarity with the tools and workflows introduced. Participants are welcome to bring and utilize their own computers capable of accessing the internet and running a web browser. Tutorials will involve simple scripting operations in the Python language. The conda utility will be used to install libraries. Both QGIS and VisIt packages will be used for visualization.

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Of interest for:
  • Terrestrial Working Group
  • Coastal Working Group
  • Hydrology Focus Research Group
  • Coastal Vulnerability Initiative
  • River Network Modeling Initiative