A major disaster disables the national economic core

Likelihood, two years

2Unlikely

to end-2028

Likelihood, ten years

3Possible

to end-2036

Systemic impact

1Limited

global

National impact

4Severe

typical highly exposed nation

Onset pace

Days

Duration (acute phase)

30 days (acute phase)

Warning time

Days (none for the earthquake variant)

Scope

National

Recovery horizon

Years (two-year reconstruction)

Capability load

Hard 1/3Soft 2/3Economic 2/3

domains loaded High

Concurrency

Standalone

triggers 4 · triggered by 2

Confidence · movement

medium

new

Rated at Standard Severe. Event reach: single-nation event (The probability that a given nation experiences the Standard Severe event in its principal economic concentration. Risk is clustered in nations with one dominant city on a hazard-exposed site.). Source of scores: model-panel-v0.5.

A flood, storm, fire, heat emergency or earthquake strikes the nation's principal economic concentration. The hazard is the one most relevant to that nation, calibrated to a common consequence: 10 per cent of the population affected and direct damage equal to 8 per cent of annual GDP. Key transport, water and health assets in the core operate below half capacity for 30 days. Reconstruction takes two years and insurance covers less than half the loss. The scenario does not impose an identical physical hazard on every nation. It tests evacuation, continuity of essential services and recovery finance. It is the only natural-hazard test among the twenty.

1. 1

   The hazard strikes the principal economic concentration, affecting 10 per cent of the population and destroying buildings and infrastructure worth 8 per cent of annual GDP.

2. 2

   Warning, evacuation and building standards determine deaths and injuries. Where alerts arrive late or people do not act on them, casualties rise sharply.

3. 3

   Transport, water and health assets in the core operate below half capacity for a month. Power and telecommunications outages slow the response.

4. 4

   Firms in the core stop work. Ports, airports and logistics hubs close and suppliers and customers elsewhere in the country lose inputs and markets.

5. 5

   Insurance pays less than half the loss. Households, small firms and municipalities carry the rest or wait for public support.

6. 6

   The central budget funds relief and reconstruction through reallocation and borrowing. Sovereign spreads widen where fiscal space is thin.

7. 7

   Displacement, interrupted schooling and deferred health care persist through a two-year reconstruction. Some firms and residents do not return.

8. 8

   Insurers reprice or withdraw cover in the affected districts and an inquiry assigns responsibility, which shapes public confidence in the authorities.

Government

Relevance 4/5

Exposure

Warning and evacuation systems, continuity-of-government sites, flood defences and building-code enforcement, finance arranged before the event and the capacity of city authorities.

Actions

• Test evacuation of the core at full scale and publish the compliance rate
• Arrange contingent credit, catastrophe bonds and reserve funds sized to a loss of 8 per cent of GDP
• Move operations centres, registries and backup sites outside the mapped hazard zone

Watch

• Condition surveys of embankments, dams and drainage
• Insured share of residential and commercial property in the core
• Seasonal forecasts and seismic hazard updates

Technology

Relevance 3/5

Exposure

Data centres, exchanges, base stations and cable landing points sited in the core, the delivery of alerts and the duration of backup power.

Actions

• Hold recoverable copies of registries and payment systems in a second region
• Extend backup power at base stations and exchanges to at least 72 hours
• Test cell-broadcast alerts against the full population of the core

Watch

• Hazard maps set against the location of critical sites
• Results of backup power and fuel resupply tests
• Recovery time achieved in failover exercises

Investors

Relevance 5/5

Exposure

Property insurers, reinsurers, sovereign and municipal debt, mortgage books, utilities and firms with a single site in the core.

Actions

• Screen assets and suppliers for location in the core hazard zone
• Stress sovereign and municipal credit for an uninsured loss of 4 to 5 per cent of GDP
• Reflect the possible withdrawal of insurance cover in property and mortgage valuations

Watch

• Reinsurance renewal prices and terms
• Insurer exits and the growth of public pools by district
• Sovereign use of contingent credit and catastrophe bonds

Public

Relevance 4/5

Exposure

Households and small firms in the hazard zone, above all those without insurance, savings, bank accounts or identity documents.

Actions

• Know the evacuation route and the conditions under which to leave
• Keep water, medicines and copies of documents for 72 hours
• Check what the household insurance policy covers and excludes

Watch

• Official alerts and evacuation orders
• Local hazard maps and the state of defence works
• Changes in the price and availability of home insurance

Triggers

• S05 Legitimacy rupture · A relief effort seen as failed or unfair, close to an election or succession, can open a dispute over lawful authority.
• S06 Breadbasket failure · Only where the core is also a major grain-producing or grain-exporting region; the loss then counts as one of the two failures.
• S02 Global funding seizure · Only where the core is a global financial centre. Elsewhere the effect is a wider spread for one sovereign.
• S18 Public service leap · Relief payments after a disaster expose paper delivery and create a mandate to replace it

Triggered by

• S06 Breadbasket failure · The heat and drought behind the breadbasket failures can produce the heat emergency or fire variant in the same season.
• S04 Hybrid coercion · A power and telecommunications blackout during extreme heat or cold turns a manageable event into an emergency in the core.

Amplified by

• S02 Global funding seizure · Closed markets and wider spreads remove the borrowing that funds reconstruction.
• S05 Legitimacy rupture · Competing authorities cannot direct evacuation, relief or reconstruction.
• S10 Severe pandemic · Hospitals already beyond surge capacity cannot take casualties or evacuated patients.

Amplifying trends

Climate change & physical riskUrban population concentrationInfrastructure ageing & maintenance backlogInsurance retreat & insurabilityDisaster risk financeEarly-warning coverageDams, reservoirs & flood defenceLocal & city government capacity

Key trends

Resilient construction & asset adaptationCriticalDisaster risk financeCriticalInfrastructure ageing & maintenance backlogVery highDams, reservoirs & flood defenceVery highClimate change & physical riskVery highInsurance retreat & insurabilityVery high

From GINC Trends: the trends rated Very high or Critical for this scenario, of 250. All S07 trend scores.

Source of scores: model-panel-v0.5. Confidence refers to the rating, not the scenario. Calibration sources are listed with the anchors above and on the scenario methodology page.

• Whether the common calibration should be a damage share of GDP, as specified, or a common return period, given that 8 per cent of GDP implies very different hazard intensities across nations.
• How to treat small island and city states, where the core is most of the country and direct damage can exceed annual GDP.
• Whether a heat emergency, whose deaths are diffuse and whose physical damage is small, fits a specification defined by direct damage and asset capacity.
• Whether a two-year reconstruction period holds for lower-income nations, where recovery from comparable events has taken longer.

No signed commentary in this build.

Version

0.5.0 · active · core-disaster

Change log

• 0.5.0 · 9 October 2026 · Rebuilt in the second pass from Catastrophic disaster in the core: the event is now calibrated to a common consequence (10 per cent of the population affected, direct damage of 8 per cent of GDP, key assets below half capacity for a month) instead of a common return period; likelihood and impact each lowered one step; macro-financial and industry loads raised to High.

Full change log