Global · Conflict
Nuclear War
SevereThe use of nuclear weapons in a conflict between states, whether by intent, escalation or error.
- Likelihood
- Low per year, but rising and cumulative
- Impact
- Existential for the northern hemisphere; global for climate
- Horizon
- Any day
Background
What this actually is
Roughly 12,000 warheads exist, held by nine states. Around 2,000 are on high alert, meaning launch decisions are compressed into minutes. Most of the arms-control architecture built during the Cold War has lapsed or been suspended, and every nuclear-armed state is modernising rather than reducing.
The realistic pathways are not a bolt-from-the-blue first strike. They are escalation from a conventional war, a false alarm in an early-warning system, or the use of a low-yield 'tactical' weapon that fails to stay tactical.
Beyond blast and radiation, the systemic risk is nuclear winter: soot lofted into the stratosphere by burning cities cools the planet and collapses global agriculture. Modelling suggests even a regional exchange could cause multi-year harvest failure worldwide.
Aotearoa
What it means for New Zealand
New Zealand is nuclear-free and not a plausible target, which makes it one of the better-modelled survival regions in nuclear winter studies — maritime climate, food surplus, low population. The threat to NZ is second-order and severe: total collapse of trade, fuel, pharmaceuticals and communications, plus multi-year cooling that would damage the agricultural sector everyone would then depend on.
Watch for
Early warning signs
- Nuclear-armed states withdrawing from remaining treaties or resuming testing
- Doctrine shifts toward first use or lowered thresholds
- Direct conventional conflict between nuclear powers
- Evacuation or dispersal of a state's leadership
Action
How to prepare
- 01
Understand fallout basics: distance, shielding and time — a solid interior room for the first 48 hours removes most of the danger
- 02
Stored potassium iodide is only relevant to radioiodine exposure, not a general fix
- 03
Hold food, water and medicine for weeks, not days — the trade shock reaches NZ before any physical effect
- 04
Battery or wind-up radio for RNZ National, the designated emergency broadcaster
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
Get prepared
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