How a Solar Storm Two Years Ago Nearly Caused a Catastrophe On Earth

schwit1 writes: On July 23, 2012, the sun unleashed two massive clouds of plasma that barely missed a catastrophic encounter with the Earth's atmosphere. These plasma clouds, known as coronal mass ejections (CMEs), comprised a solar storm thought to be the most powerful in at least 150 years. "If it had hit, we would still be picking up the pieces," physicist Daniel Baker of the University of Colorado tells NASA. Fortunately, the blast site of the CMEs was not directed at Earth. Had this event occurred a week earlier when the point of eruption was Earth-facing, a potentially disastrous outcome would have unfolded.

"Analysts believe that a direct hit could cause widespread power blackouts, disabling everything that plugs into a wall socket. Most people wouldn't even be able to flush their toilet because urban water supplies largely rely on electric pumps. ... According to a study by the National Academy of Sciences, the total economic impact could exceed $2 trillion, or 20 times greater than the costs of a Hurricane Katrina. Multi-ton transformers damaged by such a storm might take years to repair." Steve Tracton put it this way in his frightening overview of the risks of a severe solar storm: "The consequences could be devastating for commerce, transportation, agriculture and food stocks, fuel and water supplies, human health and medical facilities, national security, and daily life in general."

Comments

It happened before

[Guspaz]

In the 80s, Quebec's power grid got taken out by solar storms. It was particularly susceptible because we have a ton of really long-distance runs:

https://en.wikipedia.org/wiki/...

That one was just bad enough to flip circuit breakers on the grid, but it still caused a 9 hour power outage. Some satellites also lost control.

Re:FUD filled....

[Ol Olsoc]

And no, a solar flare can not burn out giant motors and generators, all that can be ran easily without the SCADA system. In fact we used to run drills operating the place by hand, as most of the guys that did it from 1940 until 1990 did it mostly by hand.

You should research the Carrington event before you declare this all FUD

http://en.wikipedia.org/wiki/S...

In March 1989 much of Quebec lost power for the same thing.

Related are EMP pulses. We can make these ourselves. The Starfish prime and Soviet Project K tests got some old school electrical equipment all goofed up.

In short, huge induced currents in places where they shouldn't be can knock out the old school equipment - it just takes a big enough event. The little, more sensitive stuff we use today? Maybe we should look at it as a huge job creation plan fixing/replacing all the stuff that gets broken.

Re:FUD filled....

[Sockatume]

A solar storm isn't like a local EMP happening everywhere at once. It has a much lower intensity. It affects things like power grids is because they're spread over an enormous area, so the induced currents add up, but it won't even tickle systems that are disconnected from that grid.

Low probability of getting hit by CME

[Walking The Walk]

I don't see what the fuss is about. The odds of being hit by a CME have to be quite low. Let's work it out together:

1. To make the math simple, let's first assume CMEs can be fired in any direction.
2. For a CME to hit the Earth, it has to occupy the same space as us at the same time.
3. The Earth is approx 1 AU from the sun at any given time; so to hit the Earth, the CME has to hit a particular spot on a sphere of space 1 AU in radius.
4. So the probability of a given CME hitting Earth is approximately equivalent to the ratio of half the Earth's surface area (since only half faces the Sun at a time) to the surface area of a sphere with a radius of 1 AU.

Google says:

1. 1 AU = 149,597,871 km
2. Surface area of a sphere is 4*pi*r^2, so our orbital sphere has an area of approx 2.8 x 10^17 km^2.
3. Surface area of the Earth = 510,072,000 km^2, or 5.1 x 10^8 km^2

Therefore the probability of being hit by a given CME is (2.8 x 10^17) / (5.1 x 10^8) = 5.5 x 10^-8, or a 0.0000055% chance.

Now the number of CMEs per year is actually higher than I expected, which I suppose explains why we do in fact get hit between 0 - 70 times per year. However the number of annual large CMEs is quite low, with none of the sites I visited actually agreeing on the number (most seemed to agree it's less than 5 per year in a solar maximum.) Let's say there are 5 per year. That only brings the chance of being hit by one of them up to 0.000028% per year. So if I live to be 100, the chances I'll see one in my lifetime are only 0.0028%.

caveat: These calculations ignore CME cross-section (essentially width and height) and duration (essentially length), since I couldn't find any accurate information on those. If you find those, you can factor them into these calculations by multiplying by the cross-section, multiplying by the % duration that the CME's strength is high, and multipyling by the Earth's average orbital velocity. That will modify the probility to take into account the volume of space the Earth occupies while the CME is traversing the edge of our 1 AU sphere, and how much of the surface of the sphere is touched by the CME.