Introduction
Gridded hydrologic models represent the spatial variation in hydrologic parameter values using a grid of uniformly sized cells. This differs from traditional "lumped" hydrologic models commonly used in Australia, which represent the spatial variation in hydrologic parameter values using comparatively large homogeneous sub-catchments. Therefore, providing suitable spatial (i.e., GIS) input information is available, a gridded model has the capacity to provide a more reliable representation of the spatial variation in hydrologic parameter values across a catchment.
GSSHA (Gridded Surface Sub-Surface Hydrologic Analysis) is a gridded (i.e., distributed), physics-based hydrologic model. It's features include, but are not limited to, the following:
•2-dimensional overland flow;
•1-dimensional stream flow;
•1-dimensional infiltration; and,
•2-dimensional groundwater movement.
Further detailed information, including a User Manual, tutorials and guidance on input information can be found at the GSSHA wiki webpage (www.gsshawiki.com).
The large number of grid cells in a typical gridded model necessitates the use of some specialised GIS software in order to assign suitable parameter values to each grid cell. Accordingly, a GSSHA interface has been developed and incorporated within CatchmentSIM to generate all required GSSHA input files.
The following pages provide an overview of the GSSHA interface that has been developed within CatchmentSIM. The interface allows you to create a GSSHA model within CatchmentSIM, run a simulation and extract discharge hydrographs at any location within your CatchmentSIM boundary.
The information provided in this section includes:
•Program Reference: provides a description of each section of the GSSHA interface;
•Example Application: Provides an example application of GSSHA for the Macleay River catchment.
