External forcing of the thermosphere and ionosphere

The thermosphere-ionosphere system is driven to a particularly high degree by the input of energy from external sources. This energy input comes mainly from solar radiation and the interplanetary magnetic field with the solar wind. Cosmic rays also contribute to the variability of the system. The topic area Externally Driven Coupling Processes works on the characterisation and quantification of the solar influence on the variability of the thermosphere-ionosphere system. The work includes climatological studies as well as the analysis of the impact of special solar events (coronal mass ejections, etc.) using qualitative and statistical investigations of observational data and results from physical models. The aim is to improve the understanding of the physical links between solar driver variability and ionospheric variability, and to model and use the results to predict the formation of ionospheric disturbances and their propagation dynamics.