Likelihood, two years3Possibleto end-2028
Likelihood, ten years4Likelyto end-2036
Systemic impact2Moderateglobal
National impact5Catastrophictypical highly exposed nation
OnsetSudden
Duration (acute phase)30 days (acute)
Warning timeNone to days
ScopeNational
Recovery horizonYears
Capability loadHard 1/3Soft 2/3Economic 0/3domains loaded High
ConcurrencyStandalonetriggers 4 · triggered by 0
Confidence · movementhighnew

Rated at Standard Severe. Likelihood type: idiosyncratic. Source of scores: ginc-desk-v0.2.

03Narrative

Dateline: February 2028

The rain that was forecast as 'heavy' delivers a year's total in eight hours over the metropolitan area. Underpasses, metro lines and the basement data centres of three banks flood before the first alert reaches phones; the alert system itself depends on a tower that loses power at 19:40. The main port is closed for a month, the airport for nine days. Insurers report 400,000 claims in a week and a quarter of the damaged homes have no cover. The hospital that serves the district is evacuated by boat. Six weeks later, the national accounts show the quarter's output down 4 per cent and the fiscal cost at 2 per cent of GDP before reconstruction begins. An earthquake variant plays out in a different capital: 50,000 dead, two million homeless, the building-code enforcement failures of 30 years visible from the air. In both, the question that decides the recovery is not the size of the hazard but whether the state can register, house, treat and pay a few million people at once, and whether anyone trusts the numbers it publishes.

The dateline is illustrative, not a forecast. The narrative is hypothetical; the historical anchors below are real events.

04Summary

A once-in-a-century flood, storm, fire, heatwave or earthquake strikes the nation's main population and economic centre. v0.2 widened the scenario from climate to seismic hazards, since the Swiss analysis ranks earthquake third of 44 hazards and the 2023 Türkiye–Syria and 2025 Myanmar earthquakes were the deadliest disasters of the period. Following the Swiss method, every nation is assessed at one common 'major' intensity so that hazards can be compared; the hazard type is a parameter.

05Historical anchors

EventDateWhat happenedCalibrates
Valencia floods29 October 2024Over 220 deaths; alert failures; months of recoverywarning and alert failure
Los Angeles wildfiresJanuary 2025Insured losses around US$40 billion; among the costliest wildfires on recordurban fire, insurance gap
Hurricane HeleneSeptember 2024Over 200 deaths across the US south-east; inland flooding far from the coastcascading inland impact
Pakistan floods2022A third of the country under water; 33 million affected; damage around US$30 billionnational-scale flood, low income
Türkiye–Syria earthquake6 February 2023Over 50,000 deaths; damage estimates above US$30 billion for Türkiyeseismic variant
Myanmar earthquake28 March 2025Magnitude 7.7; thousands dead; response constrained by conflictcompound with S07
Swiss national risk analysis2025Earthquake third, inland flooding fifth, windstorm sixth, drought seventh, heatwave ninth of 44 hazardshazard ranking precedent

06Parameters

Shown at their preset values. Parameters are not adjustable in this release and nothing on this page is computed from them. Custom settings run (Phase B) but are labelled 'non-standard run' and excluded from comparisons.

Common sliders at Standard Severe · read-only

1. Severity
majorsevere (Standard Severe)extreme
2. Duration (acute phase)
30 days (Standard Severe)90 days1 year3 years5 years
Standard Severe: 30 days (acute)
3. Onset
sudden (Standard Severe)rapid (weeks)gradual (years)
4. Warning time
none (Standard Severe)daysmonths
Standard Severe: none to days
5. Scope
national (Standard Severe)regionalglobal
6. Origin
natural (Standard Severe)accidentaladversarial (great power / neighbour / non-state)
7. External support
fullpartial (Standard Severe)none
8. Concurrency
standalone (Standard Severe)plus one named scenarioplus two
9. Policy response assumed
none (pure exposure)current plans executed (Standard Severe)best practice
Standard Severe: current plans
10. Recovery horizon
monthsyears (Standard Severe)structural

Scenario-specific parameters · read-only

ParameterDefaultRange or optionsNote
Hazardfloodoptions: earthquake / wildfire / storm / heatwave—
Return period1-in-1001-in-50 to 1-in-500—
Share of population exposed15 per cent5–40—
Share of GDP in affected zone25 per cent10–50—
Insurance penetration30 per cent5–70—
Cascading infrastructure failureyes——

07Transmission channels

  1. Physical destruction and casualties.
  2. Infrastructure outage: power, water, transport, communications.
  3. Health system overload.
  4. Business interruption and supply-chain breaks.
  5. Insurance and fiscal cost.
  6. Displacement and housing.
  7. Political accountability and trust.

08Capability loading

High: capability band shifts expected under current plans. Medium: band shifts under 'none' policy response only. Low: strain without band shift. Loads are judgement-based until the Atlas connects. Domains link to the Atlas.

DomainLoadChannel
Hard
Defence and securityMediummilitary aid to civil authorities; search and rescue
Strategic infrastructureHighgrid, water, transport, telecoms resilience and repair
Critical technologyLowearly warning, geospatial data
Soft
Government effectivenessHighemergency management, alerts, reconstruction, registration and payments
Human capitalHighhealth surge, schooling disruption, mental health
Influence and cohesionMediumtrust in authorities; solidarity
Economic
Macro-financialMediumfiscal cost, insurance sector, output loss
Industry, trade and supplyMediumports, factories, logistics
Energy and resourcesMediumgeneration and fuel distribution

09Stakeholders

Government

Relevance 4/5
Exposure
Alert systems, building codes, emergency funds, insurance backstops
Actions
  • Test alerts at scale
  • Fund pre-arranged financing (cat bonds, contingent credit)
  • Enforce codes
Watch
  • Hazard forecasts
  • Insurance withdrawal from regions

Technology

Relevance 3/5
Exposure
Data-centre siting, telecoms resilience, alert delivery
Actions
  • Geographic redundancy
  • Cell-broadcast alerts
Watch
  • Flood and fire risk maps

Investors

Relevance 3/5
Exposure
Insurers, municipal debt, real estate
Actions
  • Physical-risk screening by asset
Watch
  • Cat model updates
  • Reinsurance pricing

Public

Relevance 4/5
Exposure
Household preparedness and insurance
Actions
  • 72-hour kits
  • Flood and fire plans
Watch
  • Official alerts

10Regional exposure

RegionExposureRationale
North AmericaHighHurricanes, fire, earthquake
EuropeMediumFloods, heat
ChinaHighFloods, typhoons, earthquakes
Indo-PacificHighTyphoons, earthquakes, Pacific cyclones
South AsiaHighFloods, heat, earthquakes
Gulf and Middle EastMediumHeat, flash floods, Türkiye and Iran seismic
AfricaHighFloods, drought, low coverage
Latin America and CaribbeanHighHurricanes, earthquakes, El Niño
Russia and EurasiaMediumCentral Asian seismic; wildfire

11Early-warning indicators

IndicatorSourceThreshold
Seasonal forecasts and ENSO state——
Cat model loss estimates——
Insurance availability by region——
Alert system test results——
Building-code enforcement audits——
Reservoir and river levels——
Urban heat records——
Seismic monitoring——

12Compounds

Triggers
Triggered by
None directly
Amplified by
Amplifying trends
climate change raising hazard frequencyurbanisation in exposed zonesinsurance retreat
Key trends

From the GINC 250: trends rated Very high or Critical for this scenario. All S10 trend scores.

13Rating rationale

RatingBand or levelWhy
Likelihood, two years3PossibleA 1-in-100 event in the core is about 1 per cent a year per hazard, higher across multiple hazards and under climate change.
Likelihood, ten years4Likely—
Systemic impact2ModerateUnless the core is a global hub.
National impact5Catastrophic—
ConfidencehighHazard science is mature.

Source of scores: ginc-desk-v0.2. Confidence refers to the rating, not the scenario. Calibration sources are listed with the anchors above and on the methodology page.

14Open questions

Contested assumptions for the panel to resolve.

  • Whether to assess at a common return period or a common intensity (the Swiss choice).
  • How to treat small island states where the core is the whole country.
  • Whether heatwaves, whose deaths are diffuse, belong with sudden-onset hazards.

15Commentary

No signed commentary in this build.

16Version and citation

Version
0.2.0 · active
Change log
0.2.0 · 2 October 2026 · Entered the Library at v0.2 with GINC desk scores.
Full change log
Cite asGINC (2027). Scenario S10 Catastrophic disaster in the core, Scenario Library v0.2. scenarios.ginc.org/library/catastrophic-disaster-coreContent and data are published under CC BY 4.0.