Nations Must Plan for 'Black Swan' Catastrophes, Scientists Warn

A massive volcanic eruption that dims the sun for months. A solar storm that fries electrical grids across continents. A nuclear war that poisons the soil and sky. These are not Hollywood premises. They are scenarios that environmental scientist Florian Ulrich Jehn believes governments need to take seriously enough to plan for them now, before they happen.

In a recent analysis, Jehn makes a straightforward case: the official risk registers that guide national security planning in countries like the UK and Switzerland are built to handle disasters measured in thousands of deaths and billions of dollars in damage. They stop there. They do not model what happens when a single event—whether natural or human-caused—breaks the global food system. They do not game out famine on a continental scale, or the months-long blackouts that would follow a severe solar storm, or the agricultural collapse that would follow a nuclear exchange. Yet the historical record suggests these catastrophes are far more probable than most governments assume.

Jehn's argument rests on a single observation: all three of these scenarios share one devastating common denominator. A volcanic winter, a prolonged power failure, or nuclear winter would each produce the same cascading outcome—the sudden inability to grow and distribute food at scale. The specifics differ, but the result is identical. This convergence is what makes the threat real enough to warrant formal planning.

The problem is structural. Current national risk assessments are built around scenarios that fit neatly into existing frameworks. They account for earthquakes, floods, pandemics—events with historical precedent and measurable probability. Black Swan events, by definition, fall outside those bounds. They are rare enough that they do not appear in standard risk models, yet consequential enough that their occurrence would reshape civilization. The gap between what governments officially prepare for and what could actually happen is enormous.

Jehn proposes three concrete steps. First, nations should formally incorporate these low-probability, high-impact scenarios into their national risk assessments. This is not about predicting the future with precision; it is about acknowledging that certain catastrophes, however unlikely in any given year, are possible enough to warrant contingency planning. Second, governments should negotiate emergency trade rules before a crisis strikes. When food becomes scarce, countries typically ban exports to protect their own populations. These panic-driven restrictions worsen global shortages and accelerate famine. Pre-negotiated agreements could prevent this cascade. Third, governments should fund research and pilot projects for resilient crops—plants that can be grown with minimal sunlight or fertilizer, the kind of agriculture that might sustain populations if normal farming became impossible.

The stakes are not abstract. If a major volcanic eruption occurred tomorrow, or if a solar storm knocked out power infrastructure across the Northern Hemisphere, or if a nuclear exchange poisoned the atmosphere, the immediate deaths from the event itself would be dwarfed by the secondary deaths from starvation. These are not speculative numbers. They are the logical consequence of a food system that depends on continuous electricity, global trade, and stable weather. Remove any of those three, and millions die—not from the initial disaster, but from the collapse that follows.

Jehn's argument is not that these events are likely. It is that they are possible, that their consequences would be catastrophic, and that the cost of planning for them is trivial compared to the cost of being unprepared. Governments spend enormous resources preparing for scenarios they consider plausible. The question he is asking is whether they can afford not to prepare for scenarios that are rare but ruinous.