↳ ↑ What are Geomagnetic Disturbances?

This page is part of the project "Understanding HF Propagation."
by Doron Tal, 4X4XM

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.

Solar Wind
Figure 1: The solar wind interacts with Earth’s magnetosphere causing auroras.

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.

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