I first learned about this possibility a few months ago at a conference organized by Empact America, a bipartisan, non-profit organization concerned exclusively with the EMP challenge. Scientists there explained about "severe space weather" - in particular, storms on the surface of the sun that could trigger an EMP event.
The strongest solar storm on record is the Carrington Event of 1859, named after Richard Carrington, an astronomer who witnessed the super solar flare that set off the event as he was projecting an image of the sun on a white screen. In those days, of course, there was nothing much to damage. A high-intensity burst of electro-magnetic energy shot through telegraph lines, disrupting communications, shocking technicians and setting their papers on fire. Northern Lights were visible as far south as Cuba and Hawaii. But otherwise life went on as normal.
The same would not be true were a solar storm of similar magnitude to erupt today. Instead, the infrastructure we depend on would be wiped out. Most of us would not adapt well to this sudden return to a pre-industrial age.
How likely is a repeat of the Carrington Event? Scientists say it is not only possible -- it is inevitable. What they don't know is when. The best estimates are that super solar storms occur once every 100 years - which means we are 50 years overdue.
Both the EMP Commission and a 2008 study by the National Academy of Sciences (NAS) call for a response: hardening the electrical grid and other components of the infrastructure to increase the chances they would survive, as well as pre-positioning spares of essential but complex components of the electrical grid and other infrastructure critical to communications and emergency public services.
And it would certainly help if scientists could learn to reliably forecast solar storms. If we know one is coming, there are steps that can be taken to reduce the destruction. In particular, the electrical grid could be shut down; planes could be grounded (Air Force One is designed to withstand an EMP attack but other planes would fall from the sky); citizens would be instructed not to stay home - in particular, to stay out of their cars which would stop working -- until the storm subsided.
President Obama has pledged $100 million to help Haiti recover from its recent earthquake. By coincidence, that's precisely the amount that the NAS recommends be spent on measures it believes would limit the damage resulting from an EMP event by 60 to 70 percent. When you consider that such an event - whether naturally occurring or a "man-caused disaster" -- could cause trillions of dollars in damage and claim more lives than were lost in World War II, that sounds like a reasonably priced investment.