Parameterisation and calibration of a grid based distributed hydrological model

Abstract

Parameterisation of hydrological models using remote sensing is currently being studied in a European Union funded ARSGISIP project. Input to hydrological models consists of meteorological data, discharge data and spatial data (slope, soils, land-use and vegetation cover) for model parameterization. Satellite imagery has been found to be a valid data source for the purpose of hydrological modeling. However, as this data is generically in raster format its use in vector based hydrological models can be difficult. Our solution to the problem is the creation of a threedimensional raster based hydrological model, H3mod. The model has built-in GIS functionality and includes a graphical user interface for running the model on Microsoft Windows platfroms. All relevant hydrological parameters can be set individually for each grid cell. H3mod performs quite well under northern Scandinavian conditions such as cold winters, spring flood due to snowmelt, low relief and water logged conditions in marshes and mires. Presently the model is being applied in three basins in the boreal forest of northern Finland, varying in size from 20 to 2500 km2, and so far the results are promising. Future model enhancements will include water quality (sediment, phosphorus andnitrogen) modeling capabilities.