On September 1 and 2, 1859, telegraph systems around the world failed catastrophically. Telegraph operators said they received electric shocks, telegraph paper ignited and were able to operate the equipment with batteries disconnected. During the evenings, the Northern Lights, more commonly known as the Aurora Borealis, could be seen as far south as Colombia. Typically, these lights are only visible at higher latitudes, in northern Canada, Scandinavia, and Siberia.
What the world went through on that day, now known as Carrington Eventwas a huge geomagnetic storm. These storms occur when a large bubble of superheated gas called plasma is ejected from the surface of the sun and hits the Earth. This bubble is known as a coronal mass ejection.
The plasma of a coronal mass ejection 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 Northern Lights and other natural phenomena. Inasmuch as Electrical Engineer who specializes in the power grid, I study how geomagnetic storms also threaten to cause power and internet outages and how to protect against them.
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 ice core samples from Antarctica have shown evidence of an even more massive geomagnetic storm that occurred around 774 AD, now known as the Miyake event. This solar flare produced the largest and fastest increase in carbon-14 ever recorded. Geomagnetic storms trigger large amounts of cosmic rays into Earth’s upper atmosphere, which in turn produce carbon-14a radioactive isotope of carbon.
A geomagnetic storm 60% smaller than the Miyake event occurred around the year 993 AD. Ice core samples have shown that large-scale geomagnetic storms with similar intensities to the Miyake and Carrington events occur at an average rate of once every 500 years.
Today, 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 of 1 to 5, with G1 being minor and G5 being extreme. The Carrington event would have been rated G5.
It gets even scarier when you compare the Carrington event with 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 of the time. There was no way to measure the magnetic fluctuation of the Miyake event. Instead, scientists measured the increase in carbon-14 in tree rings from this period. The Miyake event produced a 12% increase in carbon-14. By comparison, the Carrington event produced less than 1% increase in carbon-14, so the Miyake event likely eclipsed the G5 Carrington event.
cut off the power
Today, a geomagnetic storm of the same intensity as the Carrington event would affect far more than telegraph wires and could be catastrophic. With growing reliance on electricity and emerging technologies, any disruption could result in billions of dollars in monetary loss and risk to life dependent systems. The storm would affect most electrical systems that people use every day.
Geomagnetic storms generate induced currents that flow through the power grid. The geomagnetically induced currents, which can exceed 100 amps, flow through electrical components connected to the network, such as transformers, relays and sensors. One hundred amps equals the electrical service provided to many homes. Currents of this size can cause internal damage to components, resulting in large-scale power outages.
A geomagnetic storm three times smaller than the Carrington event occurred in Quebec, Canada in March 1989. The storm caused the collapse of the Hydro-Quebec electrical network. During the storm, magnetically induced high currents damaged a transformer in New Jersey and tripped grid circuit breakers. In this case, the failure caused five million people without electricity for nine hours.
In addition to power outages, communications would be disrupted globally. Internet service providers could fail, which would prevent the different systems from communicating with each other. High frequency communication systems such as ground-to-air, shortwave, and ship-to-shore radios would be disrupted. Satellites orbiting Earth could be damaged by induced currents from the geomagnetic storm burning their circuit boards. This would lead to disturbances in telephone, internet, radio and satellite television.
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Additionally, when geomagnetic storms hit Earth, increased solar activity causes the atmosphere to expand outward. This expansion changes the density of the atmosphere where the satellites are in orbit. Higher density atmosphere creates a trail on a satellite, which slows it down. And if it’s not maneuvered into a higher orbit, it may fall back to Earth.
Another area of disruption that can affect everyday life is that of navigation systems. Virtually all modes of transportation, from cars to airplanes, use GPS for navigation and tracking. Even portable devices such as cell phones, smart watches, and tracking beacons depend on GPS signals sent from satellites. Military systems rely heavily on GPS for coordination. Other military detection systems such as over-the-horizon radars and submarine detection systems could be disrupted, hampering national defense.
In Internet terms, a geomagnetic storm of the magnitude of the Carrington event could produce geomagnetically induced currents in submarine and land cables that form the backbone of the internet as well as the data centers that store and process everything from emails and text messages to scientific datasets and artificial intelligence tools. This would potentially disrupt the entire network and prevent servers from connecting to each other.
It’s a question of time
It’s only a matter of time before Earth is hit by another geomagnetic storm. A storm the size of a Carrington event would be extremely damaging to electrical and communication systems around the world with outages lasting for weeks. If the storm is the size of the Miyake event, the results would be catastrophic for the world with potential outages lasting months or even longer. Even with space weather warnings from NOAA’s Space Weather Prediction Center, the world would only have minutes to hours notice.
I think it is essential to continue to look for ways to protect electrical systems against the effects of geomagnetic storms, for example by install devices that can protect vulnerable equipment like transformers and developing strategies to adjust grid loads when solar storms are about to hit. In short, it is important to work now to minimize disruption from the upcoming Carrington event.