GCRI · Systemic Risk Management
Cascades and interdependence
Systemic risk arises when systems depend on one another, so that a failure in one travels into others: a power outage stops water pumping, a port closure stalls manufacturing, a cyber incident halts payments. Cascades can amplify a modest shock into a large loss, or be absorbed by buffers and substitutes. This page sets out how cascades develop and propagate, how dependencies are mapped, and what the evidence serves for those responsible for connected systems.
Cascades and interdependence on the record.
Cascades and interdependence: how the risk develops.
Network, common-cause and correlated failures. The dossier below sets out how the risk develops, what is measured, where the data come from, how it is modelled and who decides.
Failure propagates through dependency
When one system supplies another with power, data, materials or services, its failure removes an input the second system needs. Each link adds a path, and paths combine into chains that cross sectors and borders.
Buffers set the timing
Stocks, backup generation, redundant routes and spare staff delay the effect of a lost input. The cascade arrives when the first buffer runs out, which can be hours or months after the trigger.
Concentration creates single points
Where many systems rely on the same supplier, hub, cloud region or chokepoint, one failure reaches all of them at once. Concentration often grows unseen because each dependent made a reasonable choice alone.
Feedback amplifies the loss
Losses can feed back: an outage reduces revenue, which cuts maintenance, which raises the chance of the next outage. Reinforcing loops turn a contained event into a longer and wider one.
Hazards and exposure in Asia.
Population density, flood water and night lights over Asia, from NASA GIBS. Each layer carries its own date.
The interactive map needs JavaScript; the layer list and sources are below.
Layers 3
Hazards and exposure, for this page
About this layer
- Evidence
- Estimated
- Source
- Gridded Population of the World v4.11 (NASA SEDAC (CIESIN, Columbia University))
- Provider
- NASA SEDAC (CIESIN, Columbia University)
- Licence
- CC BY 4.0
- Vintage
- null; Census-based estimate, static (2020)
- Resolution
- about 1 km grid
- Uncertainty
- Census-based estimate of people per square kilometre in 2020, shown as exposure context; not a count of people affected by any hazard.
- Reached through
- gibs.earthdata.nasa.gov, only after you allow the live map
About this layer
- Evidence
- Observed (clouds leave gaps)
- Source
- VIIRS Global Flood Product (NASA LANCE)
- Provider
- NASA LANCE
- Licence
- NASA open data
- Vintage
- daily; Satellite detection; clouds leave gaps
- Newest at build
- 2026-10-14
- Resolution
- about 250 m grid
- Uncertainty
- Satellite detection; clouds leave gaps. Satellite or model raster as the provider publishes it. Clouds, swath gaps and retrieval error leave gaps and noise; values are indicators, not measurements at a place.
- Reached through
- gibs.earthdata.nasa.gov, only after you allow the live map
About this layer
- Evidence
- Observed
- Source
- VIIRS Black Marble (VNP46A2) (NASA LAADS DAAC)
- Provider
- NASA LAADS DAAC
- Licence
- NASA open data
- Vintage
- daily; Satellite radiance, corrected for moonlight and atmosphere
- Newest at build
- 2026-10-12
- Resolution
- about 500 m grid
- Uncertainty
- Satellite night-time radiance for the date shown; lights are a proxy for electricity use and outages, not a measurement of supply or access.
- Reached through
- gibs.earthdata.nasa.gov, only after you allow the live map
About this layer
- Evidence
- Observed
- Source
- VIIRS NOAA-20 corrected reflectance (NASA LANCE)
- Provider
- NASA LANCE
- Licence
- NASA open data
- Vintage
- daily; Satellite image
- Newest at build
- 2026-10-14
- Resolution
- about 250 m grid
- Uncertainty
- Satellite image. Satellite or model raster as the provider publishes it. Clouds, swath gaps and retrieval error leave gaps and noise; values are indicators, not measurements at a place.
- Reached through
- gibs.earthdata.nasa.gov, only after you allow the live map
About this layer
- Evidence
- Observed (clouds and overpass timing leave gaps)
- Source
- VIIRS NOAA-20 375 m (FIRMS) (NASA LANCE FIRMS)
- Provider
- NASA LANCE FIRMS
- Licence
- NASA open data
- Vintage
- daily; Satellite detection; clouds and overpass timing leave gaps
- Newest at build
- 2026-10-13
- Resolution
- about 500 m grid
- Uncertainty
- Satellite hot-spot detections for the day shown, including gas flares and industrial heat; not a confirmed fire, an incident report or a warning.
- Reached through
- gibs.earthdata.nasa.gov, only after you allow the live map
About this layer
- Evidence
- Observed (persistent cloud still leaves gaps)
- Source
- VIIRS NOAA-20 Level 3, 8-day (NASA LANCE)
- Provider
- NASA LANCE
- Licence
- NASA open data
- Vintage
- 8-day; Satellite 8-day composite; persistent cloud still leaves gaps
- Newest at build
- 2026-09-14
- Resolution
- about 1 km grid
- Uncertainty
- Satellite skin temperature of the ground over the 8 days ending on the date shown, a heat exposure indicator; not air temperature, heat index or a heat warning.
- Reached through
- gibs.earthdata.nasa.gov, only after you allow the live map
Keyboard, with the map focused
Hold Ctrl or ⌘ and scroll to zoom
Latest available
NASA GIBS / EOSDIS · ASTER GDEM (METI, NASA) · Blue Marble (NASA) · © OpenStreetMap contributors (ODbL) · Natural Earth
Loading the latest NASA imagery.
Drag to move. Ctrl or ⌘ and scroll, pinch or the buttons to zoom; hover for the values under the pointer; reset returns to the region.
Hazards and exposure, framed on Asia.Satellite and model products as NASA publishes them, each with its own date. They are indicators, not assessments of any place.
Data: NASA GIBS · ASTER GDEM · Blue Marble · © OpenStreetMap contributors · Natural Earth · NASA EONET · U.S. Geological Survey · NASA JPL OPERA DIST-ALERTSources and licences
- We acknowledge the use of imagery provided by services from NASA’s Global Imagery Browse Services (GIBS), part of NASA’s Earth Science Data and Information System (ESDIS). Colours redrawn from the published colour map; values averaged into hexagonal cells where shown (modified). NASA open data
- We acknowledge the use of imagery provided by services from NASA’s Global Imagery Browse Services (GIBS), part of NASA’s Earth Science Data and Information System (ESDIS). Colours redrawn from the published colour map; values averaged into hexagonal cells where shown (modified). NASA open data
- Center for International Earth Science Information Network (CIESIN), Columbia University. 2018. Gridded Population of the World, Version 4 (GPWv4): Population Density, Revision 11. NASA Socioeconomic Data and Applications Center (SEDAC). Licensed under CC BY 4.0. Colours redrawn from the published colour map; values averaged into hexagonal cells where shown (modified). doi:10.7927/H49C6VHW. CC BY 4.0
- VIIRS near-real-time products (flood, land surface temperature, snow cover, corrected reflectance), NASA LANCE; imagery via NASA GIBS. Colours redrawn from the published colour map; values averaged into hexagonal cells where shown (modified). NASA open data
- VIIRS Black Marble night-time lights, NASA Goddard Space Flight Center; distributed by the NASA Level-1 and Atmosphere Archive and Distribution System (LAADS DAAC); imagery via NASA GIBS. Colours redrawn from the published colour map; values averaged into hexagonal cells where shown (modified). NASA open data
- NASA Fire Information for Resource Management System (FIRMS), VIIRS 375 m active fire product, NASA LANCE; vector tiles via NASA GIBS. Colours redrawn from the published colour map; values averaged into hexagonal cells where shown (modified). NASA open data
- ASTER GDEM is a product of METI and NASA (ASTER Global Digital Elevation Model V003, NASA LP DAAC); imagery via NASA GIBS. Colours redrawn from the published colour map; values averaged into hexagonal cells where shown (modified). Cite as: NASA/METI/AIST/Japan Spacesystems and U.S./Japan ASTER Science Team (2019). ASTER Global Digital Elevation Model V003. doi:10.5067/ASTER/ASTGTM.003. NASA open data
- Made with Natural Earth. Free vector and raster map data @ naturalearthdata.com. Public domain
- © OpenStreetMap contributors (ODbL), via NASA GIBS (coastlines, boundaries, roads and place names). Colours redrawn from the published colour map; values averaged into hexagonal cells where shown (modified). ODbL
- Blue Marble, NASA Earth Observatory; imagery via NASA GIBS. Colours redrawn from the published colour map; values averaged into hexagonal cells where shown (modified). NASA open data
- Context on the globe and flat map: coastlines, boundaries, roads and place names from NASA GIBS reference layers (OpenStreetMap data, ODbL, © OpenStreetMap contributors); Blue Marble imagery as an optional base; 3D terrain and the elevation read-out from the ASTER GDEM elevation colour index (5 m to 200 m classes, exaggerated for legibility). Boundaries are drawn as published and imply no position on any territory.
- Live events: NASA Earth Observatory Natural Event Tracker (EONET); events are indicative and keep their original source links.
- Live: NASA EONET Events are indicative, not authority warnings.
- Live: U.S. Geological Survey Events are indicative, not authority warnings.
- Observed (EO): NASA JPL OPERA DIST-ALERT (contains modified Copernicus Sentinel data 2026). We acknowledge the use of imagery provided by services from NASA’s Global Imagery Browse Services (GIBS), part of NASA’s Earth Science Data and Information System (ESDIS).
- NASA GIBS: We acknowledge the use of imagery provided by services from NASA’s Global Imagery Browse Services (GIBS), part of NASA’s Earth Science Data and Information System (ESDIS).
- River discharge forecast, 30 days with range (GloFAS via Open-Meteo): Contains modified Copernicus Emergency Management Service information 2026; not a flood warning.
- Weather data by Open-Meteo.com (https://open-meteo.com/), licensed under CC BY 4.0 (https://creativecommons.org/licenses/by/4.0/).
- Optional layers (11 sources in the layer list: live, forecast, observed and context) print their provider credit on the map and here when switched on; forecasts are model output and derived indices are estimates.
Layers and dates
- Population density, 2020: Population: CIESIN, Columbia University, Gridded Population of the World v4.11 (2018), NASA SEDAC, CC BY 4.0 · static
- Flood water, 3-day composite: VIIRS Global Flood Product, NASA LANCE · 14 Oct 2026
- Night-time lights, daily: VIIRS Black Marble (VNP46A2), NASA LAADS DAAC · 12 Oct 2026
- True colour: VIIRS NOAA-20 corrected reflectance, NASA LANCE · 13 Oct 2026
- Active fires and thermal anomalies: VIIRS NOAA-20 375 m (FIRMS), NASA LANCE FIRMS · 13 Oct 2026
- Land surface temperature, day, 8-day composite: VIIRS NOAA-20 Level 3, 8-day, NASA LANCE · 14 Sep 2026
The cascades this topic studies run through the five domains.
- EnergyCouplingPower loss is the most frequent trigger of cross-sector cascades.What to watchServices without backup power
- WaterCouplingWater and power depend on each other in both directions.What to watchJoint water and power outage records
- FoodCouplingFood shocks cascade through prices into health and stability.What to watchPrice transmission after supply shocks
Cascade analyses are designed for the Scenario and Stress-Test series. Interdependency classes follow Rinaldi and colleagues (2001), and propagation models would carry model cards under NS-12 of the proposed Nexus Standards.
- Documented cascades with a source for every step.
- Permitted dependency data for a city or sector.
Model cascades and interdependence as a system. Run the cascade.
Assembled from the Nexus Standards area profile Global and systemic risk: the hazards it names, the systems and sectors that carry the loss, the controls that dampen it and the data that observe it. Choose the components, pick an initiating hazard and step through the cascade. The Map view places the run on an example geography with open data. Every coupling weight is a stated assumption you can change. A teaching model, not a forecast, an assessment or a certification. To model a place of your own choosing, open the full System Builder.
Hazards
- Dam failure
- Financial contagion
- River flood (set off downstream)
- Flash flood (set off downstream)
- Mass displacement (set off downstream)
- Widespread power outage (set off downstream)
- Water supply shortfall (set off downstream)
- Sovereign debt crisis (set off downstream)
- Currency crisis (set off downstream)
Systems and couplings
- Global and systemic risk
- Compound and cascading hazard standards Mechanism
- Financial stability and prudential risk Mechanism
- Supply chain and trade risk Cascade
- Future generations and long-term risk Common driver
Controls
NS-0Constitution and principlesNS-3Risk record UNIs (grammar, legacy crosswalk, allocation authority)NS-9Contextual UNIs (deployments, instances, programme instances)NS-10Policies and clauses (machine-readable obligations: definition, binding, evaluation and enforcement)NS-11Verification and monitoring (evidence, attestations, zero-trust conformance observation)NS-14Conformance and crosswalk to external standardsNRS-H120Hazard family: Structural fragility of interconnected systems (NHS-1 sys.fragility)NRS-C6Systemic and cascading riskNRS-H61Hazard family: Cascading failure (NHS-1 sys.cascade)NRS-H62Hazard family: Compound and multi-hazard events (NHS-1 sys.compound)NRS-H94Hazard family: Systemic cyber events (NHS-1 cyber.systemic-cyber)NRS-H60Hazard family: Supply-chain and flow disruption (NHS-1 sys.supply-chain)
Observation
- INFORM Risk Index (listed for reference)
- World Bank Open Data and World Development Indicators API (listed for reference)
- IMF data services (WEO, IFS, FSI via SDMX) (listed for reference)
- Direct economic loss attributed to disasters in relation to global GDP
- Macroeconomic Dashboard
Example geography
- Bangladesh: 134 hexagonal cells
- Night lights tonight, outages (VIIRS Day/Night Band), NASA GIBS
- Surface water through cloud, 30 m (OPERA DSWx-S1 radar), NASA GIBS
- Rain rate, last half hour (IMERG), NASA GIBS
- Surface soil moisture (SMAP), NASA GIBS
What is measured, and how well.
Each indicator carries its unit, its cadence, the kind of source behind it and the evidence label a value would carry. No values are shown: a programme supplies them under its own authority.
| Indicator | Unit | Cadence | Source type | Label |
|---|---|---|---|---|
| Mapped critical dependencies | count of supplier and service dependencies recorded | annual | Dependency inventories | DECLARED |
| Single points of failure | count of dependencies without a substitute | annual | Dependency analysis | ESTIMATED |
| Buffer endurance | hours or days of operation after loss of an input | per asset | Continuity plans and asset records | DECLARED |
| Supplier concentration | Herfindahl-Hirschman index of spend or volume | annual | Procurement records | OBSERVED |
| Cascade depth in scenarios | number of systems affected downstream | per scenario | Interdependency models | MODELLED |
| Restoration sequence time | hours to restore dependent services | per event | Incident and restoration records | OBSERVED |
How cascades and interdependence is modelled, measured and tested.
The model, its assumptions, its data and its uncertainty, in the form a scientist or engineer would check. Structures follow published methods. The values drawn are illustrative, not findings.
System model
The couplings between the systems in cascades and interdependence: signs of influence, a reinforcing and a balancing loop, and cross-links where stress jumps.
Where the evidence comes from.
Named public datasets and institutional records, each with its licence class. Sources by agreement are used only under their terms and never republished.
| Source | What it gives | Licence class |
|---|---|---|
| Incident reports from infrastructure operators and regulators | Documented failures with their causes and downstream effects | Public records, terms per publisher |
| UNDRR Global Assessment Report | Analysis of systemic and cascading risk across sectors and scales | Public, UN terms of use |
| OECD national supply and use tables and Inter-Country Input-Output tables | Economic dependencies between industries and countries | Open, OECD terms of use |
| Grid and network operator outage databases | Records of outages, duration and customers affected | Public summaries; full data by agreement (to check) |
| Academic interdependency case libraries | Reconstructed cascades from past events, with methods described | Licence per publication |
Who decides, and what the evidence serves.
Systemic Risk Management prepares evidence. The decisions below are taken by the authorities named, under their own rules, and never by the platform.
| Who decides | The question | Evidence this page serves |
|---|---|---|
| Infrastructure operators | Which upstream dependencies need backup, diversification or contractual protection | Dependency maps; single points of failure; buffer endurance |
| Emergency management agencies | Which services must be restored first after a widespread outage | Restoration sequences; cascade scenarios with timing |
| Sector regulators and competition authorities | Whether concentration in a shared provider needs oversight | Concentration analysis with its data gaps stated |
| Treasury and planning ministries | Where public investment in redundancy reduces the most shared exposure | Cascade depth in scenarios; restoration evidence |
Outputs this topic produces
- Dependency maps across energy, water, communications, transport and finance
- Cascade scenarios with buffers and timing stated
- Concentration analysis of shared suppliers, hubs and providers
- Restoration sequencing notes for interdependent services
What cascade analysts ask.
- Which components, if they failed, would cause the widest loss across the system?
- Which apparently independent risks are in fact correlated through a common cause?
- Where are the feedback loops that could amplify a shock rather than damp it?
- How close is the system to a threshold beyond which recovery becomes much harder?
How cascades work.
In a network, each node carries load or provides service to others. When a node fails, its load shifts to neighbours. If they are close to capacity, they fail too, and the cascade continues until the remaining system can carry the load or the network fragments. Highly connected hubs make networks robust to random failures but vulnerable to targeted or hub failures.
Common-cause failure defeats redundancy. Two backup systems that share a power supply, a software version, a supplier or a location may fail together. Correlation often rises under stress: assets, markets and infrastructures that move independently in normal times move together in a crisis. Feedback loops, such as forced selling or panic buying, can turn a moderate shock into a severe one.
How cascades are analysed.
- 01
Network models
Network science and contagion models simulate how failures spread across a mapped network. They depend on knowing the network, which is often partial.
- 02
Fault and causal networks
Fault trees and Bayesian networks represent how combinations of failures lead to outcomes. They capture common causes when those causes are known.
- 03
Dependence modelling
Statistical models of joint extremes, from probability and statistics, capture tail dependence. Data on joint extremes is scarce by nature.
- 04
Agent-based models
Simulate behaviour of many interacting actors. They are useful for insight but hard to validate.
How it is studied, and what the methods cannot say.
- 01Network science and contagionDependency network mapping · Centrality and concentration · Failure propagation simulationApplied here
- 02Scenario design and stress testingCross-sector scenario design · Reverse stress testing · Second-round effectsApplied here
- 03Reliability and resilience engineeringRedundancy and diversity design · Graceful degradation planning · Recovery time analysisApplied here
- 04Probability and statisticsFrequency and severity modelling · Dependence between risks · Combining data and judgementApplied here
- 05Uncertainty quantification and model validationPropagating input uncertainty · Separating kinds of uncertainty · Deep uncertainty framingApplied here
Where this page’s references lead.
The bodies and documents this page is read against. Status and editions change; each link goes to the issuing body.
Where this page leads across the Consortium.
Questions and answers.
What is a cascading failure?
What is the difference between systemic and cascading risk?
Can cascades be predicted?
Is redundancy enough to prevent cascades?
Why do correlations rise in a crisis?
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