How can a geomagnetic storm affect HF propagation?

Geomagnetic storms occur when eruptions from the sun send a wave of charged particles toward Earth. Because Earth's magnetic field lines converge at the North and South poles, these charged particles are funneled directly into the high-latitude regions, known as the auroral zones. When these particles crash into the polar ionosphere, they cause a massive increase in the D-layer's ionization, which severely absorbs high-frequency (HF) radio signals. As a result, HF signal paths that pass through or near the polar regions are significantly degraded or entirely blacked out. Options suggesting an improvement in HF propagation or an effect on ground wave propagation are incorrect. Ground waves are independent of the ionosphere, and geomagnetic storms disrupt, rather than enhance, high-latitude skywave communication.