In my talk
What Could Possibly Go Wrong last April I referred to a paper on the 2012 Coronal Mass Ejection (CME) that missed Earth by only nine days
:
Most of the information needed to recover from such an event exists only
in digital form on magnetic media. These days, most of it probably
exists only in "the cloud", which is this happy place immune from the
electromagnetic effects of coronal mass ejections and very easy to
access after the power grid goes down.
NASA has a post
discussing recent research into CMEs which is required reading:
Analysts believe that a direct hit by an extreme CME such as the one
that missed Earth in July 2012 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.
An extreme CME called the "Carrington Event" actually did hit the Earth in September 1859:
Intense geomagnetic storms ignited Northern Lights as far south as Cuba
and caused global telegraph lines to spark, setting fire to some
telegraph offices and thus disabling the "Victorian Internet."
And:
A similar storm today could have a catastrophic effect. 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.
Not to worry, because:
In February 2014, physicist Pete Riley of Predictive Science Inc. published a paper in Space Weather
entitled "On the probability of occurrence of extreme space weather events." In it, he analyzed records of solar storms going back 50+
years. By extrapolating the frequency of ordinary storms to the
extreme, he calculated the odds that a Carrington-class storm would hit
Earth in the next ten years.
The answer: 12%.
Only 12%. I'd say that CMEs need to be part of the
threat model of digital preservation systems.
10 comments:
The National Academy of Sciences report is from 2008. It doesn't appear to consider the effect of extreme CMEs on magnetic media, or the damage to electrical equipment other than the power grid itself such as computers and storage devices. Note that the world is far more dependent on the Web and the cloud than it was in 2008 when the panel estimated $2T in costs and 4 years to recover. And it seems clear that both the Web and the cloud would go away.
This is one of the recent arguments that I have seen to move to optical.
In 1987 FEMA claimed that magnetic media would not be totally obliterated by the electromagnetic pulse (EMP) in the "nuclear attack environment":
"To put all this in perspective, we must emphasize that while many types of electrical/electronic equipment could be affected or even knocked out by the EMP from high-altitude bursts, a rather small percentage overall is likely to be damaged. There are so many scientific uncertainties that remain in this area of technology that no one can state with any degree of certainty just how much damage could be expected. Certainly, some automobile ignition systems could fail, as could some portions of telephone and radio communications and airline communications, navigational aids, and electrical/electronic equipment. However, the concept of total oblivion for all electronic equipment and data stored on magnetic media (disc or tape) in all North America is a fantasy without scientific validity."
However, today's bits on magnetic media are a whole lot smaller than 1987 bits, and thus need a lot less energy to flip.
I'm looking to see if comparisons between the nuclear EMP and a Carrington event are available.
In a paper entitled The extreme magnetic storm of 1–2 September 1859, Tsurutani et al characterize the Carrington event. Comparing their results with data on EMPs makes the risks to digital data from each look quite different.
EMPs induce very high electric fields with very fast rise times, such that even a conductor a millimeter long gets enough voltage to destroy CMOS transistors. So any unshielded computer or, for example, flash memory would be history. But magnetic data would likely survive. Whether there would be anything left to read it (or the unaffected optical media) is another matter. Note that today's chips are much more vulnerable than 1987's - the 1987 report only says that hand-held radios using bipolar transistors would probably survive.
Carrington events have much lower electric fields but their fast-changing widespread magnetic fields induce enormous currents in long conductors, such as the electric grid, phone lines, and Ethernet cables. Computers and storage devices connected to the grid, or near enough to arc from it, would be history. Even buildings whose master switches were off might still catch fire as the current arced across the switch.
Fortunately, CMEs take time (.5-1 day) to travel 1AU, so there would be warning. Unplugging equipment and putting it in Faraday cages would help. I haven't found studies on the effect of the magnetic fields of CMEs on magnetic storage, but it seems plausible that the bits would survive.
However, government studies of the effect of CMEs such as this 2011 one from OECD emphasize that damage to the power grid would be extensive and outages might last years. There is much concern (e.g here), that doesn't seem to be reflected in the government reports, that such extended outages would cause many Fukushima-like meltdowns at nuclear power plants deprived of cooling power - their local generator fuel supplies run out in about a week. Losing data might be the least of our worries.
A major but not Carrington-level CME is expected the day after tomorrow (Sept 12) and another larger one probably the day after.
A group of luminaries have written an open letter to the President about how unprepared the US is for an EMP (electromagnetic pulse) from a CME or a nuclear weapon. It starts:
"The national Intelligence Council, which speaks for the entire U.S. Intelligence Community, published in its 2012 unclassified Global Trends 2030 report that an EMP is one of only eight Black Swan events that could change the course of global civilization by or before 2030. No official study denies the view that an EMP is a potentially catastrophic societal threat that needs to be addressed urgently. America is not prepared to be without water, electricity, telephones, computer networks, heating, air conditioning, transportation (cars, subways, buses, airplanes), and banking.
All the benefits of our just-in-time ecomony would come to a deadly halt, including the production of petroleum products, clothing, groceries and medicine. Think about cities without electricity to pump water to their residents."
Via Eric Berger at Ars Technica, researchers have definitely established two CMEs, one in 774-775 AD and another in 993-994 AD. Both were "several times" stronger than the Carrington event. Berger writes:
"In 2013, Lloyd's of London and the Atmospheric and Environmental Research Center estimated that the duration of power outages during a Carrington-like event today could last five months or longer for 20 to 40 million Americans at a total economic cost of $0.6-2.6 trillion."
I'd be very skeptical that US society could withstand power outages that long without collapse.
There are more details on the 774 and 993 events on Phil Plait's Bad Astronomy site.
Michael Cooney at Network World reports:
"President Barack Obama today issued an Executive Order that defines what the nation’s response should be to a catastrophic space weather event that takes out large portions of the electrical power grid, resulting in cascading failures that would affect key services such as water supply, healthcare, and transportation.
Mark Gilbert's How Space Could Trigger a Future Economic Crisis reports on a new paper in Space Weather:
"In four scenarios envisaging the economic impact of a solar storm, the mildest triggers a daily loss to the U.S. economy of $6.2 billion, or 15 percent of daily output; the worst case sees a cost of $41.5 billion, wiping out every dollar the world’s largest economy generates each day."
and:
"A study published last month by the Cambridge Centre for Risk Studies estimates that a solar storm would have the potential to wipe between $140 billion to $613 billion off the global economy in a five-year time span, depending on the severity of the impact.
The probability is 12% per decade (see above).
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