A few questions about nuclear EMP

[Velocity]

1. In the wake of a nuclear EMP attack, what sort of equipment would be needed to get power grids and electricity back up and running again? What do the repairs involve?

2. Is it possible for a nuclear weapon to emit very little EMP?

3. When a nuclear weapon causes radar blackout (makes radar coverage in the vicinity useless for several minutes,) is that EMP itself at work, or some other physics/magnetism thing?

[Lord_Feldon]

@Velocity

1. In the wake of a nuclear EMP attack, what sort of equipment would be needed to get power grids and electricity back up and running again? What do the repairs involve?

We don’t really know. There’s not a huge amount of information on the subject, due to test bans.

For such a dry, serious subject, the amount of actual data on the threat from electromagnetic pulse attack is pretty thin. Electromagnetic pulse is, of course, a real phenomenon produced by a nuclear explosion. The EMP Commission likes to point to its “years” of research based on “decades” of data on the effects of nuclear weapons. But at the end of the day, even if we understand the physics of electromagnetism, there is no credible way to model the mass effect of a pulse on a complex system like our power grid or our communications infrastructure.

[Machine_Elf]

@Velocity

2. Is it possible for a nuclear weapon to emit very little EMP?

Yes. If you want a strong EMP, you detonate the device at high altitude. EMP was expected even during the Trinity test in 1945 with the device at an altitude of just 100 feet, and they mostly managed to protect their equipment against the resulting EMP from that test. OTOH, the 1962 Starfish Prime test in which the device was detonated at an altitude of 250 miles, resulted in an EMP that was way bigger than anyone expected.

[txjim]

@Lord_Feldon

We don’t really know. There’s not a huge amount of information on the subject, due to test bans.

Actually, we have some pretty good data on the subject. Refer to MIL-STD-188 125 parts 1 and 2, it gives a pretty good idea on the methods to protect equipment. This includes long-pulse events which are the ones that would impact a power grid the most.

There are also facilities visible on Google Earth that simulate the effect in near field. EMP does not need a nuclear event to be recreated.

This does not answer the OP’s question but it’s incorrect to say that the effects cannot be known, modeled or protected against.