Many readers will have seen recent news that the aurora borealis, or northern lights, were visible deep into the South for several days. This phenomenon is caused by a geomagnetic storm that is caused by strong solar flares. Solar flares can cause problems on Earth by emitting clouds of magnetized particles and hot plasma.

The geomagnetic storm that occurred last week was the strongest storm for the last twenty years. A strong solar storm is called a coronal mass ejection, and the recent storm emitted a stream or particles aimed directly at the Earth. The storm was rated by scientists as a G5 storm, which is considered to be extreme.

We only get about a one-hour warning about a pending solar storm. The United States Geological Survey operates observatories that monitor the Earth’s magnetic field. NOAA and NASA also operate satellites at about 1 million miles from Earth that monitor the sun.

It’s highly unlikely for solar storms to directly affect people since the Earth’s outer atmosphere absorbs the worst of the ions and particles from the storm. However, geomagnetic storms can cause a lot of damage to electronics and wired networks. Solar storms tend to only last a few days, but some of the damage can be devastating. Radios can go dark during a bad storm, making it impossible to communicate with airplanes and ships. Solar storms can play havoc with telecommunications networks. Particularly vulnerable are undersea cable networks, which, due to their long length, can pick up and magnify the disruptions and blow out electronics.

Strong storms can knock out electric grids. In 1989, a storm knocked out the entire power grid in Quebec, affecting six million people. The USGS, along with NOAA, provides maps and advice to electric utilities about pending storms.

Vulnerability of Satellites and Precision GPS

Some of our most vulnerable electronics are in the many satellites that now circle the globe. Satellites sit outside the protective upper atmosphere, and the storms can damage electronics. This could force satellites to veer off course or even fall to Earth. One of the problems caused by the recent solar storms was to precision GPS. People driving in cars wouldn’t have noticed any issues, but there are applications that rely on locating things precisely. One of these applications is precision agriculture.

404 Media published an article that documented problems experienced by the GPS navigation systems in John Deere and other brands of tractors. Precision GPS allows John Deere tractors to navigate precise straight lines using Real-Time Kinematic technology that is accurate to within a few centimeters. Farmers were warned about planting new line crops like corn during the current storm since inaccurately aligned planting makes it impossible to precisely run tractors during the rest of the season for weeding, watering, and fertilizing the rows or crops. The current storm hit during the week when farmers in the Midwest were planting many of their crops.

Preventive Measures and Long-Term Solutions

There are steps that can be taken to avoid the worst damage from bad solar storms. One of the best defenses for the electric grid is to turn off the grid during the worst part of a storm. That sounds drastic, but it’s better than losing large numbers of transformers. It’s possible for electric companies to install modern transformers that provide some protection against the kinds of surges created during a solar storm. It’s also possible to design undersea fibers with some protection against solar storms.

The ultimate protection is to place electronics inside a Faraday cage, which is a wire mesh box built around all sides of the electronics device. But that’s expensive, and the Foundation for Resilient Societies estimates that putting new electronics in these cages each year would cost $25.5 billion.

But maybe that’s not expensive when considering the alternative. The National Academy of Science estimated that a disastrous solar storm could cost $2 trillion worldwide and cause a global recession when electric grids stay out of service for months.