Space weather is a catch-all term for the interactions between the solar wind and coronal mass ejections (CMEs) from the Sun as they impact Earth’s magnetosphere and ionosphere. The most common interaction is also the most breathtaking – aurora.
Space weather isn’t always harmless and beautiful. Sometimes CMEs can be powerful enough to cause widespread technical disruptions. One of the most famous modern examples occurred on March 13, 1989 in Quebec. Three days earlier, astronomers witnessed an incredibly powerful explosion on the sun. According to NASA, a billion-ton cloud of gas was released and was rushing towards Earth at a million miles an hour.
On March 12, the massive cloud of solar plasma slammed into Earth’s magnetic field. Spectacular aurora displays were witnessed as far south as Florida and Cuba. In the early hours of March 13, the powerful magnetic disturbance began affecting Quebec’s electrical grid. In less than two minutes, the entire power grid lost power.
Folks living in and around Quebec sat in darkness for 12 hours. This geomagnetic storm showed what the sun is capable of throwing our way and the damaging effects it can have on technology.
But, these effects aren’t limited to high latitude regions
A new study is out this week showing how space weather can affect equatorial regions around the world. Researchers found smaller space weather effects are amplified near the Earth’s equator. Regions once considered safe from space weather are now at risk for power grid disruptions.
Researchers poured over 14 years of data collected in space and on Earth. The findings are a surprise. Geomagnetically induced currents are amplified by the equatorial electrojet, a naturally occurring flow of current located 60 miles above the Earth’s surface.
Credit: Brett A. Carter
“The Earth’s magnetic field does the job of shielding the Earth from the solar wind and when it gets hit by these shocks, you get a global magnetic signature at the ground,” said Brett Carter, a space physicist affiliated with RMIT University’s SPACE Research Centre in Australia.
“This magnetic signature becomes locally amplified by rapid changes in the equatorial electrojet, which increases the induced current levels in the ground near the equator,” Carter added.
Carter and his fellow researchers found electrical disruptions could be caused without a massive CME, like the one responsible for the Quebec blackout.
The study shows these smaller events can damage unprotected power infrastructure and could even cause fluctuations in wholesale electricity pricing. Spikes in current can also cause temporary malfunctions in systems monitoring the rates of supply and demand.
Why are these areas more susceptible to space weather effects? The equatorial electrojet stretches above large areas of Africa, South America and Southeast Asia. Shielding electricity infrastructure isn’t exactly high on the to-do lists in these countries.
“I think this is cause for a new way of looking at the impact of adverse space weather in a largely unstudied region, where health and economic well-being are increasingly reliant on dependable power infrastructure,” added Carter.