In the project "Нigh-energy Electron Precipitation Into the atmosphere: an assessment based on balloon-borne
observations and model Calculations", we investigate the impact of energetic particles precipitating into the atmosphere on the Earth's atmosphere and the climate system. Special focus is the ionization of the atmosphere during particularly strong particle precipitation events like solar coronal mass ejections or geomagnetic storms and their impact on the chemical composition of the Earth's atmosphere. To investigate this, we carry out model experiments with our ion chemistry model ExoTIC and the chemistry-climate model EMAC.