Integration of multiple representations of elevation and process models

Abstract. This paper presents a framework to integrate process models to multiple representations. The targeted type of process models is the dynamic spatially explicit process model, an environmental process models where values are spatially distributed and the term dynamic is used to emphasize the explicit time dependency of the process model. Of the available methods to link representations stored in a Geographic Information System (GIS) to process models, the tight coupling was selected since values are directly in GIS, being adequate for the computationally intensive requirements of dynamic spatially explicit process models. The choice of which GIS to use was driven by the need to access implementations of spatial algorithms. Since only open source software provides this capability, TerraLib, an open software GIS, was selected. TerraLib provides functions to access representations stored in relational databases. Metadata about the representation is stored using a database table and the spatial capabilities of TerraLib. This representation of information contains the area where valid values exist in the representation of elevation and values describing modeling procedure including date and time of the measurement, techniques used during measurement and production, and accuracy of the representation. Optimizations were implemented to support the computationally intensive characteristic of TITAN2D. They include a cache of past queries and prediction of future queries. The solution to select the best representation is based on a ranking system that considers resolution and date and time of the representation acquisition. Keywords: dynamic process model, representation, simulation, TerraLib, TITAN2D. 1