We investigate the geoeffective events happened from 8 to 20 Sept 2011, analysing the most plausible solar sources of these events, where coronal mass ejections and coronal holes play a fundamental role. The physical properties of the coronal holes, such as area and magnetic field, are studied through the Solar Dynamics Observatory instruments: AIA 193 { \AA} images and HMI longitudinal magnetograms. The active regions which are the origin of the coronal mass ejections are analysed in AIA and SoHO-LASCO data.
Categories: astro-ph.SR