Global · Technological
EMP Event
WatchA high-altitude nuclear detonation or comparable event producing an electromagnetic pulse that destroys unshielded electronics.
- Likelihood
- Low; requires a nuclear-armed hostile actor
- Impact
- Civilisation-changing over the affected continent
- Horizon
- Tied to nuclear escalation
Background
What this actually is
A warhead detonated 100-400 km up produces three pulse components. E1 is nanosecond-fast and destroys semiconductors directly. E2 resembles lightning. E3 behaves like a severe geomagnetic storm and attacks transformers.
Effects cover the line of sight from the burst — potentially a continent from a single device. Unlike a ground burst, there are no immediate casualties, no blast and little fallout. The damage is entirely infrastructural, which is why it is attractive as a coercive option.
Recovery is slow for the same reason as a severe CME: destroyed grid transformers cannot be replaced quickly, and the factories that make them need power.
Aotearoa
What it means for New Zealand
NZ is not a plausible standalone EMP target. The realistic exposure is to an EMP event affecting a major trading partner, which produces the same trade and financial shock as any large-scale conflict. Domestic preparation is identical to CME preparation.
Watch for
Early warning signs
- Nuclear escalation indicators generally
- State actors testing high-altitude delivery capability
Action
How to prepare
- 01
Same as extended grid failure: water, food, heat, light, comms, cash
- 02
Keep a spare radio and torch in a sealed metal container if you want belt-and-braces protection
- 03
Keep older, non-electronic tools and a vehicle you can start without a network
Go deeper
Where to find more information
In an emergency
New Zealand's official channels
- Get Ready — household preparedness
- Civil Defence / NEMA
- GeoNet — quakes, volcanoes, tsunami
- MetService severe weather warnings
In a life-threatening emergency call 111. RNZ National is New Zealand's designated lifeline broadcaster — keep a battery radio.
Connected
Related threats
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