In the last decade or so, there's been an increase in disaster fiction based around the Coronal Mass Ejection (CME), or "Carrington Event", in which a solar flare destroys terrestrial power grids.
Not only has fiction run the ball on this topic, but even news organizations have jumped in on the scare mongering and would be best described as "a rambling drunk uncle".
Even National Geographic got on board, with their interactive "Survive the Blackout", though their product was more sober. On the tail end of that is a long list of assumptions that are based largely, if not entirely, on fiction. This article will attempt to separate the science fiction from the science fact, using both commissioned studies by the USAF Space Weather center, as well as historical examples that illustrate the reality of a mass CME.
First off, let's talk about the science.
What is a CME?
A coronal mass ejection is an eruption in the sun's corona that discharges charged plasma, and they occur on a cycle:
The sun has a gradual 7 year rise to a "solar maximum", and a rapid 4 year decline to a solar minimum. These eruptions are very common as the sun is rounding the maximum and beginning to start it's decline to solar minimum. This cycle plays out roughly every 11 years, though there is some ambiguity.
So what's up with the plasma?
Plasma is super-heated gas that is so hot it cannot hold on to it's electrons. This plasma is essentially the 'tail' of a solar flare, in which actual mass is traveling behind the radiation ejected from the sun during a solar flare. The plasma tends to arrive behind the actual charged particles which move at the speed of light; traveling the 92,000,000 miles from the sun requires about 8 minutes for the particles, but can take days for the plasma to arrive.
What is plasma? Plasma is super-heated gas that is so hot it cannot hold on to it's electrons.
If you don't follow that, it's ok - here's what it means to on the ground floor:
Following a Solar Flare, charged particles are thrown from the sun and they're capable of interfering with the Earth's protective magnetosphere. Ionized gasses can't maintain their change in the earth environment because they rapidly cool and stabilize. The collision of plasma and the magnetosphere creates a disturbance, and this phenomenon went pretty much unnoticed for millennia, if you weren't Inuit. The "northern lights" are a visual manifestation of this process, which is actually pretty common.
However, on September 1st, 1859, telegraph workers were stunned to find lines failing, operators being shocked, and even fires. Coincidentally, an extremely powerful CME had occurred just days before. The following disruption and mayhem became known as the "Carrington Event".
Fantasy vs Reality
The problem with CME's is that people know just enoughabout them to know they can damage electrical grids. They don't know how, where, or why.
Fiction has taken this and run with it, asserting that:
- Planes will fall from the sky (they haven't).
- Cars will fail (they haven't).
- Home electronics will be destroyed by currents (they won't in most cases, and surge protectors can mitigate the risk).
- Communications grids will collapse (very circumstantial).
- Massive, global outages could occur (Extremely unlikely, due to plasma's inability to reach mid-latitudes without stabilizing).
- The replacements parts for this infrastructure requires a long time to manufacture and there's only one plant that manufactures them... etc.
CME's *can* be serious events that do cause a lot of damage. While they won't drop a plane from the sky, they can (and do) interfere with navigation and communications equipment. These systems are all but mandatory for flight. They may not fry your car's electronic systems, but they can damage power infrastructure. Gas pumps don't work so well without electricity, and it's hard to make a purchase if the card reader is down. In 1977, a blackout in New York City left people stranded in elevators, in homes in sweltering heat or severe cold, without a way to better themselves. Violence, looting and arson was common. While that incident was not related to a CME, it does give framework within which we can see the problems of blackouts in inner city environments.
Given this, we can look at the reality of the problem and address it rationally.
The problem with CME's is that people know just enough about them to know they can damage electrical grids. They don't know how, where, or why.
History Speaks if we Listen
March 13, 1989, Quebec Canada: Several days before, an intense, X15 class charged particle event began interfering with communications and navigation equipment. It was so intense, the northern lights were visible as far south as Texas. Quebec's utility company was one of many beset by endemic power production issues. What often gets overlooked is that within minutes of the disturbance, over 200 power companies suffered similar problems.
Well, Quebec is situated on igneous rock, which facilitates Geographically Induced Currents (GIC). GIC's are what caused the grid scale level of failure of capacitors. This means Quebec was at a disadvantage from the get go.
The incident, NASA scientist Sten Odenwald called "legendary", didn't illlustrate a single incidence of a vehicle being disabled. Not a single flight crash landed. Computers likewise seem to have survived. So is there a reason to believe this is a legitimate threat?
Popular culture has people believing that a CME would return society to the stone age. The truth is, a X-class solar flare and CME could be a threat - but only to very specific environments. Just like we would plan for other localized disasters, we should look at the areas in which GIC's and latitude overlap and provide an environment in which GIC's are probable. Another consideration: since the Quebec outage, there have been numerous CME's that were much stronger. In fact, the strongest CME ever recorded occurred in 2003, and went largely unnoticed. Earlier that year, an outage unrelated to CMEs greatly impacted around 50,000,000 people, so we have facts to rely on, and other legitimate concerns to consider.
The full Government Fidings Report can be found here.
Notice that this event occurred in High-latitude GIC country.
What About Weaponized EMP?
Weaponized EMP is likewise a popular concern these days, and with some reason; The USAF in conjunction with Boeing and Raytheon have 'successfully' tested CHAMP (Counter-Electronics High-Powered Advanced Missile Project). Unlike Solar EMP, weaponized EMP uses microwaves, which aren't as affected by earth's stabilizing atmosphere.
At present, AFRL isn't talking about the specifics of CHAMP. However, it's probably safe to say that given the necessary concentration of microwaves required to fry electronics that the weapon will be specific. Microwave weapons are extremely directional, narrow in scope, and probably not aimed at your Sentra. As of the time of this writing, it's not likely EMP weapons will be used to black out a city. When they can, it won't be long before we all know, and if they they could... well, see below.
Once we've evaluated the metric of Probability and Proximity to determine our risk, we need to address Duration and Intensity. While a prolonged blackout is certainly a risky situation, it is not likely to destroy our infrastructure. We will still be able to manufacture replacement parts or make necessary repairs. This means that what we're dealing with here is a fairly normal Type II, and the methods we use to be ready for a "Carrington Event" aren't really all that different than a snowstorm, or regular blackout.
We're vulnerable to CME's, and at present there's nothing we can do to prevent them. They carry a very short "lead time", meaning we'll know what's coming, but won't have enough time to prepare. However, it wouldn't take much to have a few weeks worth of supplies on hand. Recall from "Understanding Emergencies": the specifics of what caused the emergency is less important than how you address it.
In the case of CME or EMP, we can say it's a Type II. Therefore, having enough food, fuel, and energy to get by for a few weeks should suffice. So unless you really just have nothing else to focus on, there's not much sense in wrapping everything in Faraday cages. A regular CME hasn't produced a collapse yet, and we've had some big ones.
As to weaponized EMP, and HEMP, at this time there's just not much strategic value in using those against civilian targets and their efficacy is speculative. For now, there are far more pressing concerns.