Predicting Magnetic Fields in Earth-Impacting Coronal Mass Ejections Using Data-Driven Modelling

The information of the magnetic field structure of Earth-impacting coronal mass ejections (CMEs) is a crucial missing element in improving long-lead time space weather forecasting. This knowledge can serve as a first warning of the severity of a storm and is in particular needed for constraining the flux rope parameters both in first-principle space weather simulations and in semi-empirical CME models. We present here the fully data-driven and time-dependent magnetofrictional modelling (TMFM) approach to estimate self-consistently the magnetic structure of the CME flux rope. The more specific results are shown for the CME that erupted on September 10, 2014, including the comparison to in-situ observations. We will discuss also the potential of TMFM for providing realistic information of intrinsic CME parameters for space weather modelling and improving the accuracy of long-lead time space weather forecasts.