EMP Attack

[NobleSavage]

Is this a serious threat or over blown fever mongering? I tried to do a little research but google is clogged with political sites talking about armageddon.

If you have any sound scientific links please share.

 

[dockeen]

This should give you some keywords regarding historical events.

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

 

[bilby]

Is this a serious threat or over blown fever mongering? I tried to do a little research but google is clogged with political sites talking about armageddon.

If you have any sound scientific links please share.

The only way to generate a sufficiently powerful EMP to have a widespread and significant effect is to detonate a nuclear device at high altitude. Local EMP effects can be produced using other means, but they tend to lack sufficient energy to do any significant harm, even quite close to the source.

If an enemy has the means to detonate a nuclear device at high altitude, and the motive to do so, then EMP is probably the least of your problems. EMP weapons might be useful in limiting the retaliatory response capability of an enemy during a general and large scale nuclear exchange, although most military systems are sufficiently hardened against EMP as to render this fairly ineffective; Again, in such a scenario, EMP is not the top of your list of difficulties.

So a non-nuclear EMP is going to cause negligible damage in a small area;
A nuclear EMP that is the sole attack mode is a waste of a nuke that could do a lot more damage as a direct weapon, without the need for a high altitude delivery system that is complex, expensive, and gives away your launch site, exposing you to retaliatory strikes; and
A nuclear EMP that is part of a more general nuclear strike is likely to make a bad situation a tiny bit worse, but is not going to be anywhere close to your main concern in that scenario.

All in all, EMP attack is simply not very practical. Any enemy with the capability to inflict one upon you can do a lot more harm to you in other ways.

 

[Derec]

An EMP attack would not be able to be pulled off stealthily. You need a powerful weapon and you need to detonate it in very high altitude. So we would know who was responsible and it would have to be a nation state.
Also there is much scaremongering about an EMP disabling all electronics in the US throwing us back into some sort of Revolution-like state. It would cause extensive damage but maximum electric field amplitude (in kV/m) would be only over a relatively small area with amplitude dropping off.
Also consider what a pulse is. A very short, intense pulse is a very broadband signal in the frequency domain. So passing through things like buildings, metal car bodies etc. is going to attenuate it, especially the high frequency components. Even heavy cloud cover and rain can attenuate high frequency signals several orders of magnitude.

So yes, there would be widespread damage, but maximum damage would occur over a relatively small area and whoever attacks us should chose a nice day with as little cloud cover as possible. Also, a HEMP will not bring us back to horse and buggy technology, sorry ...

 

[Jimmy Higgins]

I fear a solar flare from the sun burning out our transformers a lot more than a man made EMP. In fact, we were about one or two weeks away from just that recently, when a massive flare, suggested to be notably larger than that in the 1800s, passed our orbit, just with us about a week or two away from it.

 

[Nexus]

Obviously none of you watched Dark Angel to truly understand the after effects of a EMP attack.

 

[dystopian]

The only way to generate a sufficiently powerful EMP to have a widespread and significant effect is to detonate a nuclear device at high altitude. Local EMP effects can be produced using other means, but they tend to lack sufficient energy to do any significant harm, even quite close to the source.

This isn't an accurate assessment.

While it IS the case that to create an EMP effect over a widespread area one needs (currently) to use nukes; it is NOT at all true that non-nuclear means of EMP generation can't be significant, not do significant harm, or are only local. Analysis done for instance by Israeli counter-terrorist experts already determined 5 years ago that one could cheaply order online all of the parts you'd need to develop an EMP bomb that can bring down an airliner; and the technology has only evolved since then (while shielding our infrastructure hasn't become any more commonplace) And a number of militaries have developed non-nuclear EMP weapons that are more than powerful enough to serious targeted damage. Such a weapon when used in the right place could do very widespread damage indeed.


As to the op, here's some quick links I found:

http://www.newscientist.com/article/mg20227026.200-aircraft-could-be-brought-down-by-diy-ebombs.html
http://www.tfd.chalmers.se/~valeri/EMP.html

It *is* a concern that is to be taken serious (by those responsible for designing, building and maintaining vulnerable infrastructure and vehicles), but like with all possible threats one really shouldn't give in to fearmongering and overreact. The sky isn't falling.

 

[Tom Sawyer]

Obviously none of you watched Dark Angel to truly understand the after effects of a EMP attack.

Don't forget Ocean's Eleven. A truck-mounted EMP can knock out half of Las Vegas.

 

[Loren Pechtel]

This should give you some keywords regarding historical events.

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

Yup. The Starfish Prime incident was an accident, not a bomb engineered for EMP.

1) It was *FAR* from civilization and yet messed things up.

2) It occurred before the semiconductor era. Modern stuff is vastly more vulnerable than stuff was back then.

3) You can gang together any number of stages in an h-bomb, thus there is no upper limit to it's power.

Realistically, a large bomb in low earth orbit could turn the lights off to the horizon--and the horizon is far, far away when you're that high up. I doubt the lights would ever come back on, either--society would collapse before replacements for the fried bits could be constructed.

 

[Loren Pechtel]

An EMP attack would not be able to be pulled off stealthily. You need a powerful weapon and you need to detonate it in very high altitude. So we would know who was responsible and it would have to be a nation state.

No. Private space launch facilities exist. Whether bad guys could lay their hands on the materials needed for the bomb is another matter, though.

Also there is much scaremongering about an EMP disabling all electronics in the US throwing us back into some sort of Revolution-like state. It would cause extensive damage but maximum electric field amplitude (in kV/m) would be only over a relatively small area with amplitude dropping off.
Also consider what a pulse is. A very short, intense pulse is a very broadband signal in the frequency domain. So passing through things like buildings, metal car bodies etc. is going to attenuate it, especially the high frequency components. Even heavy cloud cover and rain can attenuate high frequency signals several orders of magnitude.

So yes, there would be widespread damage, but maximum damage would occur over a relatively small area and whoever attacks us should chose a nice day with as little cloud cover as possible. Also, a HEMP will not bring us back to horse and buggy technology, sorry ...

Check out Starfish Prime oops. That wasn't a small area.