What is a Geomagnetic Disturbance?
A geomagnetic disturbance occurs when the Earth’s magnetosphere is disrupted due to interactions with solar wind, leading to changes in magnetic field strength and plasma flow.
Figure 1: Geomagnetic Disturbance based on Kakioka Magnetic Observatory, Japan ↗
This is a typical morphology of sudden-commencement type magnetic storms (horizontal force variation).
Figure 2: The solar wind interacts with Earth’s magnetosphere causing auroras.
When a CME enters the magnetosphere, it causes a Geomagnetic Storm
Figure 3: Interaction between a CME and Earth's Magnetosphere
Figure 3: Interaction between a CME and Earth's Magnetosphere
A major magnetic storm 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.
shows near-real-time indices and explains what the terms mean.