Guest post by Steven Goddard
The Effects of One Nuclear Bomb at High Altitude
From Wikipedia
Yesterday’s missile launch from nuclear power North Korea raised particular concern in the military, due to the possibility of EMP (Electromagnetic Pulse) attack. Almost every piece of technology in our lives is dependent on semiconductors, which contain circuitry that is extremely vulnerable to electromagnetic pulses. From the Federation of American Scientists:
During the Cold War, the US military was very concerned about the fact that US planes used solid state circuitry and Soviet planes used vacuum tubes. It was known that nuclear war would likely cause American planes to drop out of the sky. Since then, we all have become completely reliant on semiconductor technology which controls our transportation, power, satellites, information technology and communication systems. Transistors have evolved over time to smaller and smaller geometries and lower voltages, which make them increasingly vulnerable to EMP.
The US and Russia conducted many nuclear detonations at high altitude prior to 1962, but the integrated circuit had not yet been invented. Some experts believe that an effective EMP attack would send the US and/or Europe instantly back to the dark ages. Civilian planes could lose control and fall from the sky, and cars made since 1980 might instantly and permanently lose steering, engine and brake control. Many phones, computers and Internet switches would become permanently disabled. Newt Gingrich spoke about the danger on Fox News this morning.
Gingrich replied: “There are three or four techniques that could have been used, from unconventional forces to standoff capabilities, to say: ‘We’re not going to tolerate a North Korean missile launch, period.’ … look at electromagnetic pulse, which changes every … equation about how risky these weapons are.”
More from Wikipedia
Ever wonder why (“Axis of Evil”) North Korea and Iran have been rushing to develop nuclear weapons and missile delivery capabilities? It has nothing to do with stopping global warming or making friends with Washington and Whitehall. Some references below. I recommend that everyone read them before they go to the voting booth next time. It is important to have leaders who can do more than talk, because we have bigger and tougher enemies than people who use incandescent light bulbs, and bankers who take holidays in Las Vegas.
ELECTROMAGNETIC PULSE THREATS TO U.S. MILITARY AND CIVILIAN INFRASTRUCTURE
http://superconductors.org/emp-bomb.htm
http://www.unitedstatesaction.com/emp-terror.htm
http://dsc.discovery.com/videos/future-weapons-emp-bomb.html
http://www.electronics-related.com/usenet/design/show/98485-1.php
http://www.janes.com/articles/Janes-Strategic-Weapon-Systems/EMP-Bomb-Australia.html
http://commdocs.house.gov/committees/security/has197010.000/has197010_1.htm
http://www.fas.org/irp/threat/mctl98-2/p2sec06.pdf
http://www.fas.org/nuke/intro/nuke/emp/toc.htm
http://www.popularmechanics.com/science/defense/1281421.html
AKD, I’ll point out that there was no mention of “fanatic, suicidal jihadis” in the article, only North Korea and Iran, each of which is developing missile systems and nuclear warheads. That phrase is of your own creation.
If the case is to be made for hurting America, while one city could be vaporized, an EMP attack could affect the entire country, in power and communications systems. Your claim of “lashing out at our personal electronics” is your own, and not part of the article.
The idea of a terrorist is to cause mass instability, and EMP weapon has the greatest far reaching ability to do that. And yes, if your “personal electronics” are fried, then it “hits home” for you even more. The reason terrorists chose 9-11-2001 is because that number “911” is known to almost every American, it was their way of making it “hit home” for everybody, not just then but for well into the future. – Anthony
“Obviously my point is the same as many… yes, it would be nasty, but NOT catastrophic and would NOT result in every moving vehicle crashing into every other. I’d be more worried about the drivers blinded by the flash, or incapable of not panicking, and the potential damage to the grid… taking us back to the other thread where people are digging up generators to run the gas pumps…”
I really, REALLY tried to not respond to this thread…but my fingers got the best of me.
Of course every singe vehicle would be impacted. And attempting to quantify the number is a rough exercise at best, but…
I believe that the Prius is “drive by wire” technology, meaning no mechanical linkage between the steering wheel and the wheels.
And I don’t know about where you live…but here in Massachusetts, take a ride on the Mass Turnpike any morning between Worcester and Boston (about 40mi) and see how many Prius’s (Priui?) are on the road, and then imagine every one of them losing control or shutting down at precisely the same instant.
That’s catastrophic in my book.
And I WON’T post in this thread again…
Really.
JimB
Actually such an attack would require a nuke designed to emit the maximum possible energy in the desired EMP energy profile range. As for delivery systems, an airplane would be quite effective too as we’ve seen from earlier incidents. If a 15 year old science geek can build a device at home and all that’s missing is the hot stuff we’ve got plenty of other potential sources of the problem since just about anyone can learn to fly a plane.
It’s easy to imagine the worst. It’s easy to destroy. What is hard is peace. What is hard is defusing situations without escalating them into the very situations you fear. What is hard is not acting upon your blood fears for when you act upon your blood fears often what happens is exactly what you wanted to avoid in the first place, or some nasty variant of it with blood on your hands.
What I don’t understand is why the North Koreans are acting the way that they do. No I don’t buy all the reasons given on the tv propaganda machine channels.
Certainly a caged animal is dangerous, especially when it potentially has fangs. The zoo keeper needs to tread lightly or might get bitten which means that South Korean will get nuked, and there goes our western civilization based upon electronics much of which is, oh dear, built in South Korea! Yikes, the threat levels are high but North America needn’t be the target directly to be seriously wounded.
Tread carefully America and don’t plunge the world into WW IV (or is that WW V by now) with reckless bravado and delusions of the bully with the bigger stick. A small knife in a fight can do serious damage to the biggest of foes.
ps. Oh, when did we all forget about Neutron Bombs?
If you are really worried about transportation after an EMP, just keep an old diesel powered vehicle with mechanical fuel injection. Hard to fry the electronics on those old guys, since they didn’t have any.
“Rich countries have already committed to paying poor countries to help them adapt to climate change but they have been at loggerheads over the best way to raise money and distribute it.”
http://www.guardian.co.uk/environment/2009/apr/06/aviation-climate-change-tax
In other words, we’ll tax our travelers and give the money to politicians in poor countries to urge them not to develop their industries. We need all the energy for ourselves so you poor nations can have our welfare and live in huts. We might even outsource some jobs to keep you happy. Just don’t develop, ok?
Actually just the opposite is the case. Even a very primitive device of low yield could impact a huge area. It only needs to be detonated at very high altitude to have large coverage. A small device in a small commercial or business jet, or small military jet detonated at is peak operating altitude could impact a large fraction of the country (like everything east of the Mississippi).
Altitude of burst is the most important factor as the generation of EMP at lower altitudes depends on non-symmetrical development of the gamma ray absorption area (deposition region) around the burst that generates the Compton electrons .
In bursts over about 19 miles altitude the gamma rays moving upward are essentially free to escape the atmosphere due to its low density at this altitude so most gamma ray absorption and Compton electron generation occurs in a pancake shaped zone below the burst point as the atmosphere thickens and becomes most effective at absorbing the energy and becoming ionized. The effected area is roughly equal to the ground area that has line of site to the burst point, with the characteristic horseshoe shape in the illustration due to the dip angle of the earths magnetic field to the north (in the northern hemisphere — the sense of the horseshoe shape would be reversed south of the equator.) The range of effects also depends on the frequency of the pulse that most effectively couples with conductors. Long conductors that couple efficiently with low frequency RF will be effected at larger distances than short conductors that only couple with high frequency RF.
A burst at 50 miles altitude would effect approximately a 600 mile radius, a 100 mile altitude burst 900 miles. As you can see the first few 10’s of miles altitude would be the most important. These sorts of altitudes are well within the range of high performance aircraft in a ballistic climb or even a crude low tech missile, or cruise missile.
This is one of the reasons that small hand held devices have relatively low sensitivity to EMP (and other EMI effects like solar storms). They simply are not very good antennas for the energy available. Long conductors like fence lines, power and phone lines, long pipe runs etc. will couple efficiently and can develop very high currents and voltages to ground with very fast rise times on the initial pulse (on the order of 5 nano second rise times). Maximum induced currents and voltages usually require conductor lengths (effective antennas) of 10’s of meters in length.
Larry
Anthony,
If you can come up with a plausible scenario in which a non-state actor could deliver a nuclear weapon to create widescale EMP effects, I will buy into it as a potential threat, otherwise we are left with state actors, and there the logic fails.
And anyways, disruptive as an EMP attack might be, turning on the television to find out that New York/LA/Houston was just incinerated is a far more effective agent of terrror than turning on the television just to find out it won’t turn on.
Steven Goddard (05:17:53) :
Lindsay,
This kind of response is uncalled for in a science blog.
It’s more likely September 11 was chosen for historical reasons:
http://answers.google.com/answers/threadview?id=291605
Your not so friendly Neutron Bomb, it’s not even about sanity. The inventor of the Neutron Bomb speaks.
Nasty stuff.
Answer to self @ur momisugly (07:22:58) :
The link shows how they can test the success of various hardening processes.
http://works.bepress.com/cgi/viewcontent.cgi?article=1004&context=george_h_baker
Wouldn’t have much effect on traffic around the DC Beltway. Traffic is at a standstill a good portion of the time anyway.
They’ll temporarily lose steering and brake control due to the drivers all trying to make the radio or CD player work. Steering and brakes are power assisted so they’ll still work with more effort; many use mechanical power boosting which won’t be affected by EMP.
CodeTech (08:55:16) :
It’s more likely September 11 was chosen for historical reasons:
http://answers.google.com/answers/threadview?id=291605
I don’t think they chose Sept 11 for any other reason than that they were finally ready. The historical Ottoman defeat context doesn’t work because the hijackers were Arabs who were oppressed by the Turks themselves. 911 emergency number connection, not so sure about either.
Some have questioned the London attacks on 7/7 and thought that there was something significant about that (seven heavens, etc). But that attack was followed by two others in Britain which occurred on dates which can’t be linked to any esotericism or historical events. Neither can the Bali or Madrid attacks.
Put any unusual dates down to coincidence. Terror is terror. If they were concerned about dates they would choose special events like Xmas.
AKD,
Even more frightening is if you can’t turn on the television or get any information.
MartinGAtkins,
Sorry you feel that way. The point is that we (still) can argue and disagree.
CodeTech (07:15:35):
After posting my comment about the clutch, it dawned on me that my comment is appropriate for the UK (mainly manual trans) but not for the US (mainly auto trans?). Thanks for filling in that gap for me!
Symon (05:29:49):
Gotta agree with most of this…
ralf ellis (01:29:41) :
>>When I’m doing 75 mph and the clutch is up, the engine isn’t going to
>>stop turning, even if all the electronics were to burn out.
Again not true.
What? How on earth is burnt out electronics going to stop an engine mechanically connected to the road?
My fuel control system is all electronic, and when the computer has a fit (once a year) everything stops. All lights and all accelleration dies and the servo brakes seem to disappear too.
Obviously, the acceleration should die. The lights should not go out, and the servo brakes shouldn’t disappear – these suggest your car has some other fault.
It is hard to say with certainty.
In that particular case it was a bit unusual since the surge was on the ground side and came from the load side of the power panel. An EMP induced surge (and most lightning surges) would come mostly down the power leads, so power panel protection would be the best first layer of protection and would clip the surge to manageable levels, then what ever got by the power panel would have again been clipped at the wall socket surge protector. Now that I include a UPS in line, that adds an additional layer of protection with the battery isolation and power switching it includes. You can also improve the effectiveness of wall plug suppressors by putting a 6 inch coil in the power lead between the surge protector and the load. Its added inductance increases the effectiveness of the surge protector, acting like a resistance to fast rising surges and improving the turn on characteristics of the surge protector (it is more likely to fire on very fast rising surges, and will fire earlier)
At the time it happened, I had no antenna side protection. If I had placed a fast acting gas gap diode in the coax, the lightning strike would have been shunted to ground at the penetration panel and never gotten into the house wiring. I had the panel and UHF bulkhead connectors installed but had not gotten around to putting in a low impedance ground like a UFER ground ( http://www.psihq.com/iread/ufergrnd.htm ) and the gas gaps.
Like any protective system (fire sprinklers, circuit breakers, safety belts, motorcycle helmets, life vests and life boats) you make your best guess about the nature of the threat and choose a protective strategy that you think is cost effective and will work “most of the time”) There is no way to guarantee protection all you can do is improve the odds.
Larry
JimB-
I live in Calgary. We don’t much go in for those hippy priui…
Not to mention, I consider the loss of the “pious” fleet to be …. a good start.
Well the hypothetical scenario; a rogue state nuke, is of course quite real; particularly since all the names have been changed to politically correct terms so we don’t have to scare the horses with this stuff.
And EMPs are real; but they are not like a nuclear radiation pulse of say neutrons or gamma rays; which can go through a lot of anything and destroy electonic stuff.
I’ve designed a lot of very sensitive analog CMOS circuitry, and some digital stuff as well. The most sensitive low light semiconductor photosensor amplifier I have ever heard of is one that I designed for a bar code reader. (I have the entire world supply of them in my desk drawer. It can easily respond to photocurrents in the low femtoAmp range.
Every single pad connecting that circuit to the ouside world; (all three of them) contains pad protection cicuits, that can withstand 15,000 Volt surges; and that is applied to the bare chip itself. By the time you get it packaged and mounted on a circuit board or substrate; the surrounding circuit impedance levels are such that you’d need your own Boulder Dam power generator to get 15,000 Volts to any of those pins.
Well I exaggerated that a bit; but if this chip was to be put into any sort of satellite system; it would first be packaged in a metal package that would suppress any nuclear radiation other than neutrons, gammas and high energy cosmetic rays; and it would also stop any EMP surges from getting to the chip at energy levels capable of zapping the chip. Even the light from a nuke blast falling directly on the photosensor diode which of course would be optically open to the world; but is also electrically Faraday shielded, would not kill the chip; but it certainly would saturate the amplifier; which because of its design can’t draw enough power from the supply to even change the junction temperatures of the transistors by any easily measurable amount.
So yes, a lot of lousy circuit designs mugh get creamed; including a lot of consumer electronics like TVs; but virtually no production IC ever leaves a semiconductor manufacturing plant today without surge protection on every single pin that comes out of the chip. You can get circuit failures due to what is known as “latchup”, where an integrated transistor structure is designed with parasitic unintended circuit elements that turn the circuit into an SCR switch (Silicon Controlled Rectifier) which is a regenerative switching circuit that latches on when triggered; and if external circuits allow the switch to draw heavy currents, then it can melt that circuit and cause a malfunction. Such problems are the result of layout errors in the design. Most semiconductor processes have layout design rules that prohibit (by the laws of Physics) latchup parasitic circuits.
So yes there is a lot of crap out there desinged by people who don’t know what they are doing, or don’t care about such defects in their designs; but the better players know better than that.
Unfortunately there is a lot of stuff in circulation that is built literally with obsolete technology, that is underprotected. I’m not so sure that the newer super small geometry semi devices like modern computer and memory chips are any more vulnerable than their recent forbears. EM waves have an energy density, and you can’t just cram an unlimited amount of energy into a given space, so the smaller the circuit elements become the less energy you can force into the space they occupy.
For example, ifa high Voltage power line happens to pass alongside your house; or your kids schoolroom; you can calculate the maximum amount of energy that it can cram into a body cell or even a cellular molecule, and possibly disrupt it, and cause cancer.
Last time I checked the energy was too low by about 27 orders of magnitude; so no way that power line can affect living cells.
George
As mentioned above there are several methods to control surges.
The first is engineering of the system itself. You design it to minimize its sensitivity to the surge threat and its effects. This is mostly done through designing around a single point ground system, minimize coupling between current paths (shielding and conduits etc.) Minimize loop volume in loop circuits and choosing components that are inherently hardened to surges (they have a safe mode of failure or by their nature have low sensitivity to upset.
At the penetrations you are basically trying to either filter the surge out or clip off its peak. Series 1:1 transformers act as low pass filters and tend to limit most surges except when their internal capacitance between windings can act as high pass filter and allow the high frequency components of the surge to couple to the secondary windings.
Ferrite beads or chokes act as low pass filters and resist passage of high frequency components on the conductor they are installed on. Shunt capacitors act as high pass filters that shunt high frequency signals to ground but do not pass low frequency signals. When combined together they become a band pass filter that easily allows the intended signal frequency to pass the choke point, but strongly limit out of band frequencies.
Zenier diodes (Tranzorb) which is basically two Zenier diodes are used to clip low voltage DC lines limiting any spikes above the design peak voltage on the line.
Metal Oxide Varistors are non-linear resistors that avalanch into conduction at voltages over their rated operating voltage for AC lines, strongly clipping voltages to slightly above their rated voltage.
Zenier diodes, Tranzorb, and MOV’s all react very quickly (if installed properly with very short leads to a good ground) to effectively clip nanosecond rise time pulses.
At the component level you again go back to basic design and engineering to use good grounding, shielding of leads and low sensitivity to upset components.
Pretty basic high quality plug in wall surge protectors are a very cost effective consumer level protection.
If you are building a house or have expensive electronics to protect and power panel protection system is a very good idea and not all that expensive at the time of construction, but less cost effective as a retrofit. At 950 Joules that Leviton system is a good start, but top end consumer plug in protectors come in higher energy ratings in the 3000 joule range like these:
http://www.ecoustics.com/amz/reviews/B00005T3Q2
http://www.google.com/products/catalog?hl=en&q=best+buy+surge+protectors&um=1&ie=UTF-8&cid=5973831175052065638&ei=R0vaSd_CBI7oMPTGkPgO&sa=X&oi=product_catalog_result&resnum=3&ct=result#ps-tech-specs
You need a minimum of 600 Joules but I like to have over 1000 joules protection on all my expensive components.
Low cost installation of discrete high power MOV’s at the power panel by an electrician that understands the need to install with short leads and good grounds is a good retrofit choice, as the components themselves only cost a couple dollars each. But most folks do not want to mess with power panel installs when after market plug in surge protectors are so readily available.
Larry
Steven, of course I read it. Without trying to minimise the serious impact of a nuclear burst of this kind, a terrorist would do much better blowing up a major city.
Furthermore, you claim that we could end up back in the ‘dark ages’. Total nonsense.
I have no idea what you do for a living, but it is clear that you are not an electronics engineer. You seem to think that integrated circuits are peculiarly vulnerable to EMPs despite the fact that all modern ICs have built in protection on every pin from electrostatic discharge, which can have a similar field strength and rapid rise time to the EMP you’re so frightened of. Again, this article is scaremongering nonsense of exactly the same kind that this website tries to refute from AGW believers.
What is rather frightening is that our president’s naivety appears so great that he wants to practically unilaterally disarm our nuclear inventories and rely on the good faith of other nuclear powers to do the same while apparently neglecting the terrorists with nukes.
Early Volvos has an electronic ignition system. Truckers could pull up next to the Volvos on the freeway and key their high power CB sets and the Volvo engine died. All this demonstrates how vulnerable our computers systems are, even those early military computers. Huge efforts have been put into making military computers less vulnerable, but our home computers and many internet servers are very vulnerable to EMP.
Well. No. Almost all eqpt these days is tested for emissions. The more protected against emissions the more protected against EMP. Autos are now hardened so they can drive near transmitting antennas and not fail. Multi KW transmitting antennas. Not puny little amplified CB sets.
Rule of thumb in designing aircraft circuits: if it will take a direct lightning strike (aircraft are designed to do this) emp will likely not be a problem. Of course a lot of testing is done to make sure.
Also note: the amount of energy absorbed depends on the orientation of the “antenna” with respect to the wave.
Steven Goddard (22:58:19) :
Mike, BBC NEWS | England | London | Airliner crash-lands at Heathrow
17 Jan 2008 … A BA passenger jet from China crash-lands short of a Heathrow runway after reportedly losing power.
Since that was the same type plane I flew, I’ve followed the investigation with interest. I had thought it was a misprogramming of the Rolls Royce engine controls that wouldn’t affect the GE engines that my airline flew, the investigators seem to have come down to fuel gelling or ice that cut off the fuel to both engines, nothing electrical. The engines will gravity feed from the tanks on their own without the boost pumps, but the extremely long flight time at high altitude supposedly dropped the fuel temp too far.
While I still have my doubts, given that the engines feed from separate tanks yet quit at the same time, I doubt an EMP would have done as much damage.
.
Retired Engineer (06:44:33) :
. . .“With nuke EMP’s, airplanes should be OK, at least for getting back on the ground.”
Except for Airbus (320 in particular) which is fly-by-wire.
Yes, they have a Nintendo joystick to wiggle, not a real yoke you get to wrestle with. I don’t know either way that they don’t have some mech backup. The only Airbus I ever rode was an Egypt Air A310, and their emergency backup system was a purple box on the bulkhead with a copy of the Koran inside. (Saw the box, so I asked.)
.
M. Simon (11:39:49) :
Rule of thumb in designing aircraft circuits: if it will take a direct lightning strike (aircraft are designed to do this) emp will likely not be a problem. Of course a lot of testing is done to make sure.
Not surprised to hear this. I’ve taken lightning strikes many times and never lost anything electrical.