Raster GIS Data (Grid data)

The actual rainfall/runoff model is a grid model calculated by Golden Software's Surfer. We can distinguish 3 categories:

1. Basic grid files with "raw data" that have to be prepared by the user. This has to be done outside of the rainfall/runoff model, for instance with ArcView Spatial Analyst. However, the model contains an interface for easy conversion of ESRI raster files (ASCII format) to Surfer grid files.
2. Grid input files that can be manipulated interactively by the user for the purpose of model calibration (inside of the rainfall/runoff model).
3. Grid output files generated by the model to store model results.