Geomagnetic disturbances occur when the Earth's magnetosphere is disrupted due to interactions with solar wind, leading to changes in magnetic field strength and plasma flow.
When CMEs enter the magnetosphere, they cause Geomagnetic Storms
![]() Figure 2: Interaction between a CME and Earth's Magnetosphere Major magnetic storms may block HF propagation (3–30 MHz) by modifying the distribution of free-electrons in the ionosphere. The project "Understanding HF Propagation," focuses on skywave propagation, shows near-real-time indices and explains what the terms mean. |