Us Army Corps Of Engineers Gridded Surface Subsurface Hydrologic Analysis Gssha Model PDF Download

This document is a primer for use of the Watershed Modeling System (WMS) interface with the physically based, distributed-parameter hydrologic model Gridded Surface Subsurface Hydrologic Analysis (GSSHA). The primary purpose of this primer is to describe how the WMS interface is used to develop inputs and analyze output from the GSSHA model. This primer also provides a brief description of the GSSHA model including the overall model formulation, processes that can be simulated, and input formats for files not supported by WMS. Along with the WMS 'how-to' information, the primer provides hints on appropriate values to use in a GSSHA simulation, potential problem areas, and trouble shooting suggestions. However, this primer is not meant to be a substitute for the GSSHA User's Manual, which should be consulted for specific information on the GSSHA model. Many of the concepts used in the GSSHA model are complex, and an in-depth knowledge of the processes involved and the solution methods available are critical for successful application of the model. It is highly recommended that users obtain and read the GSSHA User's Manual before attempting to use the GSSHA model. In addition, many of the procedures outlined in this primer are described in greater detail in the WMS Help File. User's should be aware that the GSSHA model is always in development and is constantly being improved, refined, and updated with new ideas. Typically, linkage with the WMS interface is the last task completed in new model developments, after development, implementation, and testing of the new feature in GSSHA are complete. Therefore, WMS may not support new developments in the GSSHA model. Some files that the GSSHA model uses, such as the rainfall and hydrometeorological data files for long-term simulations, are not supported by the WMS interface. Files that WMS does not support are pointed out in the primer and also in the User's Manual.