Severe Solar Storm (Carrington-Class Event)
A Carrington-class geomagnetic storm, estimated to occur roughly once per 500 years, would induce ground currents capable of destroying extra-high- voltage transformers across continental power grids simultaneously. Recovery could take one to two years due to long manufacturing lead times for these transformers. Lloyd's of London estimates economic losses of 0.6 to 2.6 trillion USD for the US alone, with more recent estimates reaching 9.1 trillion USD globally over five years in the most extreme scenario. Modern dependence on satellites, GPS, and digital infrastructure amplifies vulnerability far beyond the 1859 baseline.
Probability
Horizon: 10y
By consensus
Claims
A Carrington-class event could cause power outages affecting 20 to 40 million people in the US lasting one to two years, due to the destruction of extra-high-voltage transformers with manufacturing lead times exceeding 12 months.
Lloyd's 2013 report with AER modeling, USGS vulnerability assessments, and the 2025 Verisk analysis all converge on this finding. The transformer bottleneck is the critical path for recovery and is well-documented in power engineering literature.
While the transformer vulnerability is real, grid operators have made incremental improvements since 2013. NERC reliability standards now include geomagnetic disturbance provisions, and some utilities maintain spare transformer inventories, though the scale remains insufficient for a worst-case event.
Modern satellite constellations, including GPS, communications, and Earth observation, face existential risk from a Carrington-class event. New simulations show that radiation belt enhancement could disable or destroy the majority of low Earth orbit satellites.
Simulations published in 2025 demonstrate that Carrington-level radiation belt enhancement would expose LEO satellites to doses exceeding design tolerances. The 2003 Halloween storms caused satellite anomalies at far lower intensities.
The proliferation of satellite-dependent systems since 1859 creates a vulnerability surface that did not exist historically. GPS dependency alone touches aviation, shipping, agriculture, finance, and emergency services, making satellite loss a cascading failure trigger across multiple domains.
Indicators
- • Solar Cycle 25 producing X-class flares with Earth-directed coronal mass ejections
- • Geomagnetic storms reaching G4-G5 levels (Nov 2025 northern lights visible to Alabama)
- • Increasing density of satellites in low Earth orbit amplifying space weather vulnerability
- • Extra-high-voltage transformer manufacturing backlog exceeding 18 months globally
- • GPS-dependent systems (aviation, shipping, precision agriculture) lacking backup navigation
- • Power grid hardening investments lagging behind known vulnerability assessments
Interactions
Sources
- Lloyd's of London and AER — Solar Storm Risk to the North American Electric Grid (2013) (accessed Fri Apr 03 2026 00:00:00 GMT+0000 (Coordinated Universal Time))
- USGS — What a Solar Superstorm Could Mean for the US (accessed Fri Apr 03 2026 00:00:00 GMT+0000 (Coordinated Universal Time))
- Verisk — Understanding the Odds of a Large-Scale Space Weather Catastrophe (Jul 2025) (accessed Fri Apr 03 2026 00:00:00 GMT+0000 (Coordinated Universal Time))
- Live Science — The Next Carrington-Level Solar Superstorm Could Wipe Out All Our Satellites (accessed Fri Apr 03 2026 00:00:00 GMT+0000 (Coordinated Universal Time))
- Smithsonian Magazine — How Prepared Are We for a Rare and Powerful Solar Event? (accessed Fri Apr 03 2026 00:00:00 GMT+0000 (Coordinated Universal Time))