The hydrological modelling system J2000 - knowledge core for JAMS

Hydrological model development and application for research projects is most often a cycle of model selection, model application, model adaptation and enhancement. The reason for the adaptation of an existing one or the development of a new model is that most of the conceptual hydrological models have been developed for a specific test catchment, scale and problem focus. The transfer to other catchments, other scales or other problems very often reveals some systematic drawbacks in the model’s concept, its data and parameter needs or its capability to reflect the problem the user is interested in. This often leads to an extension of the selected model or in the worst case to model rejection. Additionally, new process knowledge becomes continuously available because of the very active research carried out in catchment hydrology world wide. From time to time this forces model updates so that the models always reflect the state of the art.