WaSiM is a deterministic spatially distributed hydrological catchment model to simulate the water cycle above and below the land surface.
The model can be used in various spatial and temporal scales. It is able to model hydrologic processes for basins with sizes of <1 km2 up to more than 100,000 km2. Detailed simulations for locations are also possible (e.g. habitats). The temporal resolution of the model ranges from minutes to several days. WaSiM can be used for both short-term (floods) and long-term simulations (long-term water balance simulations).
Depending on the general availability of data and the hydrological problem to be solved, WaSiM allows a selection from several algorithms for the simulation of a specific process. The minimum data requirements for the model are time series of precipitation and temperature, as well as raster data for topography, land use and soil properties.
WaSiM used physically based modelling approaches appropriate for the selected space and time scales. Wherever possible, model components with difficult to estimate parameters are avoided. Thus, a relatively fast and robust transferability of the model to other areas is made sure.
The spatial differentiation is realized in WaSiM by the division of the area into a grid using widely used ASCII formats. Thus, an optimal data exchange with many other models and software packages is ensured. Also, input data can be adjusted quickly and with little loss to the desired model resolution.
WaSiM is available for Windows and Linux or Unix systems. It is available for 32-bit and 64-bit versions of these operating systems and there are versions that take advantage of multi-core processors as well as of super computers by utilizing as much processors as are provided by using OpenMP and/or MPI technology