Solar wind parameters and their variations greatly influence magnetospheric activity and determine space weather conditions in the magnetosphere and on the ground. The two most important parameters determining the solar wind energy penetrating the magnetosphere are the solar wind velocity and interplanetary magnetic field (IMF) Bz. The strongest magnetospheric disturbances are caused by interplanetary coronal mass ejections (ICMEs) and their embedded magnetic fields, which can often be described as magnetic flux ropes (MFRs). In many cases, it is not fully clear what IMF features lead to the largest disturbances in the magnetosphere. Is the most crucial the duration of the negative Bz interval, the minimum Bz, or some integrated electric field that characterizes the solar wind energy flux? Which magnetic structures are more geoeffective: The highly fluctuating ones, where large negative Bz alternates with positive Bz, or sustained intervals with moderately negative Bz?
We will use solar wind and ICME models to simulate different IMF structures. These numerical results as well as spacecraft data at L1 will be used systematically as input for global magnetospheric simulations. In this way, we can study the response of the magnetosphere to different IMF configurations. Our results will be evaluated and validated with spacecraft data from heliospheric missions, geomagnetic indices, and other global magnetospheric parameters. The project will bring together experts in solar wind, ICME, and magnetospheric research. Our results will contribute to a better understanding of the geoeffectiveness of IMF disturbances and, thus, will lead to an advancement in space weather predictions.