| A distributed hydrologic model is developed at The Pennsylvania State University for use with rasterized data bases. The purpose of the model is to investigate both spatial and temporal data sets and their ramifications on microscale and macroscale hydrologic modeling. All physical drainage basin properties including area, slope, stream length, and stream order are obtained or estimated from a Digital Elevation Model. Hydrologic abstractions are presently estimated by three methods: a constant infiltration rate, curve number, and the Green-Ampt equation. Parameters for the three methods are determined or derived from data sets such as the STATSGO soil data base and land use/land cover data as obtained from thematic mapper or AVHRR data. Precipitation is to be supplied to the model as either user input based on design storms or historic storms, or predicted rainfall from a mesoscale model, such as the PSU/NCAR model used at Penn State University. Finally, once the stream network has been identified via the Digital Elevation Model, overland flow is computed by a kinematic wave approximation and channel routing by the Muskingum-Cunge method. |
