On September 1 and 2, 1859, telegraph systems around the world failed catastrophically. Telegraph operators reported receiving electric shocks, ignition of telegraph paper, and the ability to operate equipment with batteries disconnected. During the evening, the aurora borealis, more commonly known as the northern lights, can be seen as far south as Colombia. These lights are usually visible only at higher latitudes, in northern Canada, Scandinavia and Siberia.
What the world experienced that day, now known as the Carrington event, was a massive geomagnetic storm. These storms occur when a large bubble of super-hot gas called plasma ejects from the surface of the Sun and hits the Earth. This bubble is known as a coronal mass ejection.
Coronal mass ejection plasma consists of a cloud of protons and electrons, which are electrically charged particles. When these particles reach Earth, they interact with the magnetic field that surrounds the planet. This interaction causes the magnetic field to distort and weaken, which in turn leads to the strange behavior of the aurora and other natural phenomena. As an electrical engineer specializing in the power grid, I study how geomagnetic storms also threaten to cause power and internet outages and how to protect against it.
The Carrington event of 1859 is the largest recorded account of a geomagnetic storm, but it is not an isolated event.
Geomagnetic storms have been recorded since the early 19th century, and scientific data from Antarctic ice core samples showed evidence of a more massive geomagnetic storm that occurred around AD 774, now known as the Miyake event. This solar flare produced the largest and fastest rise in carbon-14 ever recorded. Geomagnetic storms release large amounts of cosmic rays into Earth’s upper atmosphere, which in turn produce carbon-14, a radioactive isotope of carbon.
A geomagnetic storm 60 percent smaller than the Miyake event occurred around 993. Ice core samples have shown evidence that large-scale geomagnetic storms of similar intensity to the Miyake and Carrington events occur on average once every 500 years.
At present, the National Oceanic and Atmospheric Administration uses the Geomagnetic Storm Scale to measure the strength of these solar flares. The “G scale” has a rating from 1 to 5 with G1 being minor and G5 being extreme. The Carrington event would have been rated in the G5 category.
It gets even scarier when you compare the Carrington event to the Miyake event. Scientists were able to estimate the strength of the Carrington event based on fluctuations in the Earth’s magnetic field as recorded by observatories at the time. There was no way to measure the magnetic oscillation of the Miyake event. Instead, the scientists measured the increase in carbon-14 in tree rings from that time period. The Miyake event produced a 12 percent increase in carbon-14. By comparison, the Carrington event produced less than a 1 percent increase in carbon-14, so the Miyake event is likely a dwarf of the G5 Carrington event.
beating by force
Today, a geomagnetic storm with the same intensity as the Carrington event would affect much more than telegraph wires and could be catastrophic. With an ever-increasing dependence on electricity and emerging technology, any disruption could result in trillions of dollars in financial losses and risks to lives that depend on the systems. The storm will affect the majority of the electrical systems that people use every day.
The National Weather Service operates the Space Weather Prediction Center, which monitors solar flares that can lead to geomagnetic storms.
Geomagnetic storms generate induced currents that flow through the electrical grid. Magnetically induced currents, which can be greater than 100 amperes, flow to electrical components connected to the network, such as transformers, relays, and sensors. One hundred amperes equals the electrical service provided to many homes. Currents of this magnitude can cause internal damage to components, resulting in widespread blackouts.
A geomagnetic storm three times smaller than the Carrington event occurred in Quebec, Canada, in March 1989. The storm caused the collapse of Quebec’s hydroelectric grid. During the storm, high magnetically induced currents damaged a transformer in New Jersey and tripped network circuit breakers. In this case, the blackout knocked out five million people for nine hours.
In addition to electrical faults, communications will be disrupted on a global scale. ISPs can go down, which in turn will eliminate the ability of different systems to communicate with each other. High-frequency communication systems such as ground-to-air, short-wave, and ship-to-shore radio will be disrupted. Satellites in orbit around the Earth can be damaged by currents induced from a geomagnetic storm that burn their circuit boards. This would lead to disruptions in telephone, internet, radio and satellite television.
Also, when geomagnetic storms hit the Earth, the increase in solar activity causes the atmosphere to expand outward. This expansion changes the density of the atmosphere as the satellites orbit. The high-density atmosphere creates drag on the satellite, slowing it down. And if it is not maneuvered into a higher orbit, it can return to Earth.
Navigation systems are another area of disruption that may affect daily life. In fact, every mode of transportation, from cars to planes, uses GPS for navigation and tracking. Even portable devices such as cell phones, smartwatches, and tracking tags rely on GPS signals sent from satellites. Military systems rely heavily on GPS for coordination. Other military detection systems such as trans-horizon radar and submarine detection systems could malfunction, potentially hampering national defense.
In terms of the Internet, a geomagnetic storm of the Carrington event scale can produce magnetically induced currents in the undersea and terrestrial cables that make up the backbone of the Internet as well as data centers that store and process everything from email and text messages. For scientific data sets and artificial intelligence tools. This could potentially disrupt the entire network and prevent servers from communicating with each other.
Just a matter of time
It’s only a matter of time before another geomagnetic storm hits Earth. A Carrington storm of the size of the Carrington event will be extremely devastating to electrical and communications systems around the world with outages continuing for weeks. If the storm were as large as the Miyake event, the consequences would be catastrophic for the world with potential outages lasting months if not longer. Even with space weather warnings from the National Oceanic and Atmospheric Administration’s (NOAA) Space Weather Prediction Center, the world will only have a few minutes to a few hours of notice.
I think it is critical to continue researching ways to protect electrical systems from the effects of geomagnetic storms, for example by installing devices that can protect vulnerable equipment such as transformers and by developing strategies to adjust grid loads when solar storms are about to strike. In short, it is important to act now to minimize disruptions from the upcoming Carrington event.
David Wallace, Assistant Professor of Electrical Engineering, Mississippi State University
This article has been republished from The Conversation under a Creative Commons license. Read the original article.