Solar Atmospheric Modelling

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Solar magnetism lies at the root of most solar and heliospheric physics. The intricate structure of the solar field, the activity cycle and the influence of the field on the heliosphere represent major quests of (astro) physics which bear directly on the human environment. The sun's magnetic field is generated by enigmatic dynamo processes in the solar interior, is organized into the highly complex patterns of solar activity observed in the solar photosphere, dominates the structure of the outer solar atm osphere (chromosphere, transition region, corona), regulates the solar wind, and affects the whole extended heliosphere into the Earth's upper atmosphere. A wealth of observational data is now available through the highly successful SOHO satellite, the Swedish 1-m Solar Telescope (SST), the Japanese Hinode satellite and the Solar Dynamics Observatory. More data will arrive through the projects under development such as Solar Orbiter, the Interface Region Imaging Spectrotraph (IRIS), the Advanced Technol ogy Solar Telescope (ATST) and the European Solar Telescope (EST). The overwhelming complexity of these new high resolution observations underscores the need for a comensurate effort into theoretical modelling. The project ``Solar Atmospheric Modelling'' aims at being such an effort. Through the first years of SAM we have developed an expertise that is much sought after internationally. We have developed the necessary tools and codes to treat 3D radiation-magneto-hydrodynamics problems with a realistic treatment of the radiation. We participate in various NASA programs. However, financial support from these programs is limited to American expenditures. This project forms a matching group in Norway in order to also locally harvest the investments alread y made. Such a modelling effort is also the ideal complement to the European Data Center for Hinode that is located at the Institute.