solar storm

— Life on Earth has developed over billions of years, largely unaffected by the solar storms that wash over our planet from time to time. But in the last 200 years, humans have become increasingly reliant on technologies that are vulnerable to these geomagnetic events. […] Solar storms drive currents of millions of amps through the electrically conductive upper layer of our atmosphere (known as the ionosphere). These currents, which can fluctuate rapidly, drive powerful magnetic disturbances at the Earth's surface that in turn induce electrical currents in the planet's crust.