Space-weather exposure index
0-10 index of space-weather exposure as the product of the space-weather hazard and space-service dependence sub-indices; mostly modelled and expert inputs, so its grade is capped.
product
equal weights · floor 0.1 where geometric
1,000 draws
normalisation, weights, aggregation
2 components
6 leaf indicators
67% minimum
modelled share ≤ 20%
From indicators to the composite
A first-order view of where severe space weather would disrupt the most; a screening measure pending observed impact data.
- Geoelectric field amplitude at 100-year return periodIndicator · IND · V/kmModelled peak horizontal geoelectric field at the surface for a 1-in-100-year geomagnetic storm, combining geomagnetic latitude, storm-time magnetic field variation and regional ground conductivity, in volts per kilometre.
- Severe geomagnetic storm days per yearIndicator · IND · d/aAverage annual number of days on which planetary geomagnetic activity reaches NOAA G4 (severe) or G5 (extreme), that is Kp of 8- or more, averaged over the latest two full solar cycles.
- Strong solar radiation storm days per yearIndicator · IND · d/aAverage annual number of days with energetic proton flux at NOAA S3 (strong) or above, averaged over the latest two full solar cycles.
- GDP in GNSS-dependent activities, shareIndicator · IND · %Share of GDP generated by activities that cannot operate normally without satellite positioning, navigation or timing (logistics, aviation, maritime, precision agriculture, telecom and financial timing), from a dependence mapping of sector value added; target-only, model-based.
- Critical services relying on satellites without backup, shareIndicator · IND · %Share of assessed critical service functions (communications to remote areas, broadcast, maritime and aviation safety, Earth observation for warning, timing) that rely on satellite links without a tested terrestrial fallback; expert-assessed.
- High-voltage grid in high geoelectric hazard zones, shareIndicator · IND · %Share of transmission line length at 220 kV or above lying where the 100-year geoelectric field exceeds 2 V/km; modelled from grid topology and geoelectric hazard maps.
- Space-weather hazard sub-indexSub-index · SUB · w 1 · 50.0%Composite of the local 100-year geoelectric field with the global frequency of severe geomagnetic and strong radiation storms.
- Space-service dependence sub-indexSub-index · SUB · w 1 · 50.0%Composite of GNSS-dependent GDP share, satellite-reliant critical services without backup and high-voltage grid in high geoelectric hazard zones.
- Space-weather exposure indexDomain index · IDX · product0-10 index of space-weather exposure as the product of the space-weather hazard and space-service dependence sub-indices; mostly modelled and expert inputs, so its grade is capped.
- Hazard and threat exposurePillar · PILLAR · 5 indicesWhat can strike, how often, how hard and who and what stands in its way?
- NXS-GRX Composite RiskComposite · COMPOSITE · four pillarsComposite = (HTE × VUL × MSF × LCC)^(1/4), each pillar on 0–10 floored at 0.1; pillar = expert-weighted geometric mean of its domain indices
Run this index's own aggregation
Set each component, change the aggregation or the weight uncertainty, and watch the interval, the class probability and each component's contribution respond.
Treatment, normalisation, weighting, aggregation, uncertainty
- Treatment
- WINSORISE
- Outlier rule
- |skew| > 2, kurtosis > 3.5
- Normalisation
- MIN_MAX
- Imputation
- NONE
- Coverage minimum
- 67% of components
- Modelled share cap
- 20% of weight
- Weighting
- equal
- Aggregation
- product
- Scale
- 0 to 10
- Uncertainty
- 1,000 Monte Carlo runs over normalisation, weights, aggregation
- Framework basis
- IPCC AR6 risk framing (hazard x exposure); NOAA SWPC space weather scales; Hazard Standard space domain
2 components, 6 indicators
Space-weather hazard sub-index w 1
Composite of the local 100-year geoelectric field with the global frequency of severe geomagnetic and strong radiation storms.
| Indicator | Unit | Evidence | Sources | Share |
|---|---|---|---|---|
| Geoelectric field amplitude at 100-year return periodIND.SPC.weather.geoelectric_field_rp100 | V/km | Class D | usgs-geoelectric-hazard, bgs-geoelectric-models, nexus-gic-model | 50.0% |
| Severe geomagnetic storm days per yearIND.SPC.weather.severe_geomagnetic_storm_days | d/a | Class A | gfz-kp-index, noaa-swpc | 25.0% |
| Strong solar radiation storm days per yearIND.SPC.weather.radiation_storm_days | d/a | Class A | noaa-swpc, goes-energetic-particles | 25.0% |
Space-service dependence sub-index w 1
Composite of GNSS-dependent GDP share, satellite-reliant critical services without backup and high-voltage grid in high geoelectric hazard zones.
| Indicator | Unit | Evidence | Sources | Share |
|---|---|---|---|---|
| GDP in GNSS-dependent activities, shareIND.SPC.dependence.gnss_dependent_gdp.share | % | Class E | nexus-gnss-dependence-model, national-accounts-value-added, euspa-market-report | 33.3% |
| Critical services relying on satellites without backup, shareIND.SPC.dependence.satellite_service_exposure.share | % | Class E | nexus-expert-assessment, itu-space-services-filings | 33.3% |
| High-voltage grid in high geoelectric hazard zones, shareIND.SPC.dependence.grid_gic_exposure.share | % | Class D | osm-power-grid, derived:nis:IND.SPC.weather.geoelectric_field_rp100 | 33.3% |
Space environment
Space weather and the exposure of space-dependent services.
| Sub-domain | Indicators |
|---|---|
| Space weather | 3 |
| Space-service dependence | 3 |
Anchor frameworks (pillar structure and definitions only): Hazard Standard space domain; NOAA SWPC scales.
All 6 space environment indicators
| Indicator | Domain | Sub-domain | Component | Unit | Levels | Crosswalks |
|---|---|---|---|---|---|---|
| Severe geomagnetic storm days per yearIND.SPC.weather.severe_geomagnetic_storm_days | SPC | Space weather | hazard | d/a | GLOBAL | UNDRR_HIPS_2025 ET0101 EMDAT nat-ext-spa-geo |
| Geoelectric field amplitude at 100-year return periodIND.SPC.weather.geoelectric_field_rp100 | SPC | Space weather | hazard | V/km | COUNTRY, ADM1, GRID | |
| Strong solar radiation storm days per yearIND.SPC.weather.radiation_storm_days | SPC | Space weather | hazard | d/a | GLOBAL | UNDRR_HIPS_2025 ET0104 EMDAT nat-ext-spa-ene |
| GDP in GNSS-dependent activities, shareIND.SPC.dependence.gnss_dependent_gdp.share | SPC | Space-service dependence | exposure | % | COUNTRY, PORTFOLIO | UNDRR_HIPS_2025 ET0102 |
| Critical services relying on satellites without backup, shareIND.SPC.dependence.satellite_service_exposure.share | SPC | Space-service dependence | vulnerability | % | COUNTRY | |
| High-voltage grid in high geoelectric hazard zones, shareIND.SPC.dependence.grid_gic_exposure.share | SPC | Space-service dependence | exposure | % | COUNTRY, ADM1 |
Space-weather exposure index, world
The world reading of this index, every country as a tile and the largest movements since the previous edition.
- Previous edition
- —
- Range since 2016
- —
- Coupled composite
- —
- Coupling score S
- —
- Pulse, latest week
- —
- Outlook, 12 months
- —
- Method
- Indicator Standard 1.0 · NXS-GRX 2026
- Draws
- 1,000
No released values yet. The first edition draws the history here with its interval band and class bounds.
Country values
- Tiles
/api/v1/public/grix/risk-products/tiles/spc/{z}/{x}/{y}.mvt- Observation key
nis:IDX.SPC.weather.space_weather_exposure:{ISO3}:{YEAR}:A
Series that read this index
Crosswalks and validity checks
Crosswalks map leaf indicators to source code lists; established indices are used for validity checks, never re-weighted as inputs.
| Code system | Leaf indicators mapped |
|---|---|
UNDRR_HIPS_2025 | 3 |
EMDAT | 2 |
Platforms, standards and ways to take part
Field and service platforms of GCRI, GRF and GRA, the Nexus Risk Standards for this domain, learning, working groups and open calls. Every link is a live page.
Cite and reuse
See this index in every country profile
Each profile shows this index with its interval and class once released.
Status
The methodology, structure and definitions of The Global Risks Index are a preparatory working draft (2026), circulated for review and comment and not for implementation. No value appears until an edition is released from a governed evidence cut; values then carry intervals, classes, sources and their correction pathway. Simulators run the published methods on numbers you choose and never show a NXS-GRX value.
What NXS-GRX is not
NXS-GRX is research and risk-analytics information. It is not a credit or ESG rating and uses no rating scale, not a benchmark for financial instruments, not official statistics, not an emergency warning or official classification, and not advice. It must not be used to evaluate natural persons. Risk classes are bands on a published scale, never rankings of countries or people.
Institutions and sources
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Avis en français
La méthodologie et les définitions du NXS-GRX sont un projet de travail préparatoire (2026). Le NXS-GRX est une information de recherche et d'analyse des risques : ni notation, ni indice de référence financier, ni statistique officielle, ni alerte, ni conseil. Les classes de risque sont des bandes sur une échelle publiée, non des classements.