All telegraph networks around the world failed on September 1, 1859. Telegraph operators reported experiencing electrical shocks and telegraph paper burning. They were also able to use equipment with batteries. In the evenings, the aurora borealis (sometimes called the northern lights) could be seen as far south and as far as Colombia. This phenomenon is usually only visible at higher latitudes such as northern Canada, Scandinavia and Siberia.
On that day, the planet was struck by a huge geomagnetic thunderstorm. This event is now called the Carrington Event. These storms are caused by a huge bubble of superheated gases called plasma that is blasted from Earth’s surface. This is known as a coronal Mass Ejection.
A cloud of protons, electrons and other electrically charged particles makes up the plasma from a coronal mass eruption. These particles interact with the Earth’s magnetic field when they reach it. The magnetic field around the Earth is affected by this interaction, causing it to weaken and distort. This in turn causes strange phenomena like the aurora borealis. As an electric engineer, I am interested in how geomagnetic storms can cause power outages and other problems.
Geomagnetic storms
Although the Carrington Event of 1859 is the largest known account of a geomagnetic thunderstorm, it is not an isolated incident.
Since the 19th century, geomagnetic thunderstorms have been documented. Scientific data from Antarctic ice cores has provided evidence of a larger geomagnetic storm that occurred around A.D. 774. This storm is now known as The Miyake Event. The solar flare caused the fastest increase in carbon-14 ever recorded. The highest levels of cosmic radiation in Earth’s upper atmosphere trigger geomagnetic thunderstorms, which produce radioactive carbon-14. This storm occurred at A.D. 993 . Evidence from ice cores has shown that large-scale geomagnetic thunderstorms of similar intensity to the Miyake or Carrington events happen on average once in 500 years.
The Geomagnetic storms scale is used by the National Oceanic and Atmospheric Administration to determine the strength of these solar eruptions. G5 is extreme, while G1 is minor. G5 would have been the rating for Carrington Event.
Comparing the Carrington Event to the Miyake Event makes it even more frightening. Based on observations of Earth’s magnetic field at that time, scientists were able estimate the strength and power of the Carrington Event. The magnetic fluctuations of the Miyake events were not easily measured. Scientists instead measured the increase of carbon-14 in tree rings over that period. The Miyake Event resulted in a 12 % increase in carbon-14. The Carrington Event had a 1% increase in Carbon-14. Therefore, the Miyake Event is likely to be more successful than the G5 Carrington Event.
Powerfullness
A geomagnetic storm with the same intensity and potential for destruction as the Carrington Event today could affect more than just telegraph wires. Any disruption could result in trillions of dollars in monetary loss, and even the risk of losing our lives due to the increasing dependence on electricity and other emerging technologies. The hurricane would impact the majority of electrical systems used every day by people.
Induced currents are generated by geomagnetic storms and flow through the electric grid. The excess 100 amperes of geomagnetically -induced currents flow into the components of the grid that are connected to it, including transformers, relays, and sensors. 100 amperes are equivalent to the electricity service that many homes receive. This kind of current can cause internal damage to the components and lead to large-scale power outages.
In March 1989, Quebec, Canada saw a geomagnetic storm that was three times smaller than the Carrington Event. The Hydro-Quebec electric grid was ripped apart by the storm. The storm caused a transformer to be damaged in New Jersey by the strong magnetically induced currents. This caused the grid’s circuit breakers to trip. The outage resulted in five millions people without power for nine hours.