The article included a powerful photograph of a transformer that was physically damaged in 1989 by a geomagnetic storm.
"More than 35 years ago, I began drawing the attention of the space physics community to the 1859 flare and its impact on telecommunications," says Louis J. Lanzerotti, retired Distinguished Member of Technical Staff at Bell Laboratories and current editor of the journal Space Weather. He became aware of the effects of solar geomagnetic storms on terrestrial communications when a huge solar flare on August 4, 1972, knocked out long-distance telephone communication across Illinois. That event, in fact, caused AT&T to redesign its power system for transatlantic cables. A similar flare on March 13, 1989, provoked geomagnetic storms that disrupted electric power transmission from the Hydro Québec generating station in Canada, blacking out most of the province and plunging 6 million people into darkness for 9 hours; aurora-induced power surges even melted power transformers in New Jersey. In December 2005, X-rays from another solar storm disrupted satellite-to-ground communications and Global Positioning System (GPS) navigation signals for about 10 minutes. That may not sound like much, but as Lanzerotti noted, "I would not have wanted to be on a commercial airplane being guided in for a landing by GPS or on a ship being docked by GPS during that 10 minutes."
The recent space weather events outlined in the quote above were all fairly small storms compared to the Carrington Event of 1859. A very large storm would bring down power grids planet wide. In other words, we'd have transforms fried like the ones in the photograph all over the world. A group of Japanese scientists calculated the probability of Earth being hit by a coronal mass ejection large enough to do that as 12% per decade.
I think the best way to interpret that last sentence is that every 10 years there is a 12% chance the sun will wipe out civilization on Earth. We could act to harden our power grid and stop that from happening, but we're not.
I blog about that inaction in the posts below: