2hats
Dust.
I'd put the toys down and concentrate on the food and water instead.
an electromagnetic pulse attack on the usa could kill 90% of americans
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I'd put the toys down and concentrate on the food and water instead.
two sheds
Least noticed poster 2007
Unfortunately it's going to be the ones with the toys who'll be getting all the food and water.
free spirit
more tea vicar?
is this right?
I've been doing a fair amount of research and application related to surge protection devices, and protection of large scale solar PV systems from lightning induced surges, and in that situation it's actually the area between the circuit that's important rather than the actual length of the cable involved.
I'd expect it to be the same for EMP vulnerability as it's essentially the same thing isn't it?
Also, the UK has a lot more buried supply cables than most countries, which protects against EMP issues, most modern metal framed, metal sheet covered buildings use the framework as a LPS, ie the frame is bonded to earth spikes in multiple places, so forms a faraday cage to protect the building from lightning strike, and have class 1 surge protection devices on the incoming mains.
Personally I'd expect an EMP situation to be a lot more sporadic in its impact than is popularly thought.
2hats
Dust.
In the densely populated areas. For a short time.
2hats
Dust.
EMP maybe. A huge CME will be a different ball game.
free spirit
more tea vicar?
http://www.publications.parliament.uk/pa/cm201012/cmselect/cmdfence/1552/1552we03.htm
It'd seem the national grid agrees with my assessment.
two sheds
Least noticed poster 2007
two sheds
Least noticed poster 2007
not even if you put aluminium foil (aka hat) over the puter?
2hats
Dust.
The UK/US/Scandinavia have certainly taken steps in power distribution to mitigate impact of such. The National Grid are planning for a Carrington sized event (every 100 years or so) which will quite possibly be disruptive to some degree to a global economy (if serendipitous orientation of the CME magnetic field with respect to the geomagnetic field or a series of such don't conspire to greatly exacerbate the circumstances). Historical records (Lloyd's/AER, 2013) of low latitude aurorae suggest such flares occur every 100-250 years (and a storm of the March 1989 impact, which caused power outages/damage in Quebec, every 35-70 years).
But we just don't have sufficient data to be sure that that's all we will ever have to deal with - we can't rule out the possibility of superflares on the Sun.
Tree ring carbon-14 studies (Miyake, 2012) suggest CMEs of ~20 times the energy are possible. Observational studies of stars of near identical properties to the Sun, using the Kepler observatory, suggest the possibility of a CME of 10-100 times a Carrington event every 800 years or so and CMEs up to a thousand times that on timescales of ~5000 years (Maehara 2012, Shibayama 2013).
It's also not just about power systems. Air transport (avionics and passenger dosage), navigation, timing infrastructure, pipelines (accelerated corrosion), transport (eg railway signalling) and various communications (even submarine fibre optic cables) are all at risk.
free spirit
more tea vicar?
ok, but let's actually look at this from a UK perspective for a change.
This will work on exactly the same principle as for surge protection from close by lightning strikes, except it's distributed over the entire country / world.
This means that any circuits that are contained within earthed metal enclosures are protected automatically, as they're inside faraday cages. So that's virtually all desk top PCs, most rack mounted servers, virtually all commercial / industrial electrical circuits, all underground supply cables, anything inside earth bonded metal clad buildings (virtually al of them) as long as the incoming supply isn't vulnerable - ie it's either underground, earth bonded concentric / SWA cable, or has class 1 / 2 surge protection on the incomer... all of that is already protected.
OK so we'll lose a few transformers, a few areas will be without power, and probably a lot of the hard wired pole mounted phone systems will cut out, and those supplied by pole mounted electrical supplies will be in trouble, and some other systems will be vulnerable, but we're in a far far better position on this than the USA because we use less but much bigger transformers, the vast majority of our LV electricity distribution network is buried, and is TN-CS with earthed bonded neutral concentric cable outers, so will be entirely unaffected, plus the fact that we've been obsessed with equipotential bonding of all metal casing, and extraneous conductive parts, particularly gas and water supplies for decades, and have building codes that require Class 1 surge protection on incomers to vulnerable commercial buildings with pole mounted incomers.
Put simply, the UK electrical supply and installation practice means that we are already a hell of a lot less vulnerable than the USA, yet nobody ever seems to bother to mention this when discussing the subject, which is usually viewed from a US standpoint.
free spirit
more tea vicar?
I've just checked the bS7671 electrical wiring regs for the UK, and section 443 pretty much mandates the use of surge protection on the incoming mains supply to protect any critical services, infrastructure, facilities etc from atmospheric surges (mainly lightning, but will also protect against CME), where the incoming low voltage supply isn't buried or doesn't use an earth bonded sheathed cable.
AFAIK this requirement has been in place for a long time, it's certainly not just a 17th edition addition to the regs.
Also, most safety critical sites have back up generation on site designed to kick in in the event of grid failure.
The carrington event was 170 years or so ago, this isn't something that is a new phenomenon, and the UK grid and electrical wiring regulations have been developed by generations of highly competent electrical engineers with full understanding of all elements of risk associated with what they're doing, and how best to mitigate that risk. It's one of the few areas that politicians haven't actually managed to completely screw things up, even with privatisation etc, so tbh the article in the OP, and similar just read like chicken little type crap to me when applied to the UK situation at least, maybe they're more true of the US situation.
AFAIK this requirement has been in place for a long time, it's certainly not just a 17th edition addition to the regs.
Also, most safety critical sites have back up generation on site designed to kick in in the event of grid failure.
The carrington event was 170 years or so ago, this isn't something that is a new phenomenon, and the UK grid and electrical wiring regulations have been developed by generations of highly competent electrical engineers with full understanding of all elements of risk associated with what they're doing, and how best to mitigate that risk. It's one of the few areas that politicians haven't actually managed to completely screw things up, even with privatisation etc, so tbh the article in the OP, and similar just read like chicken little type crap to me when applied to the UK situation at least, maybe they're more true of the US situation.
2hats
Dust.
Geomagnetically induced currents have only really become understood since events in the 80's. Key geophysical surveys have only been conducted within the last 20 years.
I don't doubt that the UK is probably one of the better prepared nations in this regard and will quite likely fare better in any event up to and including Carrington magnitude. But it is also by virtue of size, shape, location and geology in a more advantageous position than the US (relatively shorter runs of conductors - in particular those east-west, generally at a lower geomagnetic latitude and having higher ground conductivity). Some of the same factors apply in comparison to a lot of continental Europe as well. Though it is also going to suffer equally where any cross border infrastructure is affected (in particular services layered on space based assets).
I don't doubt that the UK is probably one of the better prepared nations in this regard and will quite likely fare better in any event up to and including Carrington magnitude. But it is also by virtue of size, shape, location and geology in a more advantageous position than the US (relatively shorter runs of conductors - in particular those east-west, generally at a lower geomagnetic latitude and having higher ground conductivity). Some of the same factors apply in comparison to a lot of continental Europe as well. Though it is also going to suffer equally where any cross border infrastructure is affected (in particular services layered on space based assets).
2hats
Dust.
Doubtless they are more vulnerable than they used to be. It would be hard to quantify without an extensive survey of infrastructure and mapping of ground conductivity and consideration of each nation's individual circumstances.
Virtually all the research work done in this area has been in and regarding Canada/US/UK/Scandinavia, in part due to their being at higher geomagnetic latitudes. But, case in point, South Africa has also been active in this field ever since they suffered power distribution faults during the October 2003 solar storm. They are definitely at a much lower geomagnetic latitude - it is not the only factor.
2hats
Dust.
Infrequent intense or extreme CMEs (such as discussed here) can be accompanied by low latitude aurora visible right down to equatorial regions.
For example, aurorae were seen over the West Indies, Cuba, Guatemala, India, Saudi Arabia and Egypt in Februrary 1872 (down to at least 15 N) and the Cocos Islands (12 S), Singapore (1 N) during the September 1909 storm, Samoa (14 S) in May 1921.
But the key point is that it is geomagnetic latitude which matters and in most locations across the planet this does not equal the geographical latitude. The geomagnetic poles are offset from the geographical ones.
For example, aurorae were seen over the West Indies, Cuba, Guatemala, India, Saudi Arabia and Egypt in Februrary 1872 (down to at least 15 N) and the Cocos Islands (12 S), Singapore (1 N) during the September 1909 storm, Samoa (14 S) in May 1921.
But the key point is that it is geomagnetic latitude which matters and in most locations across the planet this does not equal the geographical latitude. The geomagnetic poles are offset from the geographical ones.
Thanks, very interesting indeed. had never heard of the geomagnetic equator before. Sorry, two last questions: the threat is just the same from the south as from the north taking into account the GE? And lastly is the GE a constant or is it caused by a shifting magnetic pole or by large land masses (note the curve round Asia and Antarctica)?
2hats
Dust.
For the general purposes of estimating the likelihood of risk in advance one could treat the geomagnetic field as axisymmetric (though at any point in time it is not so - it's much more complex than that but to first order is a dipole). In other words, here 20 N geomagnetic is equivalent to 20 S geomagnetic. But, as we have discussed, there are a lot of other terrestrial/engineering factors which will further alter the risk.
The geomagnetic poles (and thus equator) are constantly moving as they arise from currents in the ocean of liquid iron mixing in the Earth's outer core and also modulated by the varying pressure of the solar wind. They wander all the time (in distorted circles daily) - a direct great circle distance of a couple of hundred km over the last century. The north geomagnetic pole is moving towards the NNW and the south towards the SSW (each is ~800 km away from their corresponding geographical poles at the moment).
One should note that for the duration of a pole reversal (or during a geomagnetic excursion) there will still be a magnetic field but it is expected to get terribly complex:
Such a situation should result in a lot more low (geographical) latitude aurorae. Expect one any time between now and a few hundred thousand years hence.
(((Valve)))Thank god I've got me valve stash in the shed
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