KKF-Model platform coupling summary report KKF01b

The Netherlands are carrying out the Delta programme to adapt their water management system to climate change and sea level rise. Adaptation needs a number of decisions regarding the way the Netherlands will organize -- in the long -term -- their flood protection system, their water supply and the distribution of this water over the different sectors and regions. To support these decisions quantative information is needed on the occurrence of different water levels with respect to floods, on the water supply and the occurrence of dry spells, on the water available and its quality needed for flushing polders, sectors as agriculture, drinking water, recreation etc etc. The only way to provide such information is by simulation, using combinations of hydrological and hydraulic models that are linked to sectoral models. Where all models are forced by climatic and sea level boundary conditions. The water management system in the Netherlands, situated within the Rhine Meuse Delta, depends on the fluctuations and rise in sea level, variations and trends in river flow, rainfall and evaporation. The delta has a highly complicated system of water distribution and the design levels for flood protection are among the highest in the world. Adaptation measures are implemented on relatively small scales. Therefore the questions asked to the results of the simulation models are increasingly detailed. This all puts substantial pressure on the level of functional and technical design of these models. It is therefore essential that these models are used in a consistent way. Even more so, many of these models cannot be run independently but should be linked to other models to solve the interactions between the different parts of the simulated (natural) system. For the deltaprogramme, a model is currenly assembled from the numerous modelling systems that occur in the Netherlands (the Detamodel). To support the building of this Deltamodel, in this Knowledge for Climate project we explore methods for linking different existing models within the spatial domain in and around The Netherlands. We investigated the chain of hydrological and hydrodynamic models needed in the Rhine/Meuse basin and the North Sea and the groundwater, water demand and distribution model (NHI) for The Netherlands. In addition, the necessary interaction between the hydrological models and land-use and nature models was investigated and a suitable structure for linking these has been proposed that is based on existing modelling systems that are developed and maintained at different research institutes in the Netherlands. In parallel the coupled running of a climate and air quality model has been worked on, resulting in detailed simulations of air quality in a changing climate. The focus is particularly on the technology, as we prepared a prototype of such a linked modelling system. It will be used later to facilitate the preparation of scenarios in the investigated areas (water, air quality, nature, land use). It will also support further research that can support the Netherlands adaptation planning. The first case studies that have been run using 30 years of ESSENCE data driving the entire modeling chain show that such diverse results as future habitat development in Lake IJssel and the coincidence of high flow in the Rhine and storm Surge in the North Sea can be obtained. We are convinced that by formalizing the model linkages in a data and modeling platform, we increase the consistency of the different scenarios