A severe space weather event, often mistakenly called a solar flare, is primarily a risk to technology, not a direct physical threat to people on Earth. While a solar flare causes a sudden radio blackout, the more significant threat is the Coronal Mass Ejection (CME). A CME is a massive cloud of magnetized plasma and charged particles that takes one to four days to travel from the sun. Earth’s atmosphere and magnetic field shield humans from the radiation. The real danger lies in the CME’s magnetic field interacting with our planet’s, which induces powerful electrical currents in long conductors on the ground.
What Happens During a Severe Solar Event
When a CME impacts Earth’s magnetosphere, it causes rapid fluctuations in the magnetic field, generating Geomagnetically Induced Currents (GICs). These GICs are quasi-direct currents that flow through the ground and into lengthy conducting systems, particularly high-voltage power transmission lines and pipelines. This current flow is the mechanism for the most severe technological threat, as it can overwhelm and permanently damage high-voltage transformers.
The flow of GICs can drive a transformer core into half-cycle saturation, leading to intense localized heating. This results in catastrophic failure and widespread, long-duration power outages. For example, the 1989 geomagnetic storm caused the collapse of the Hydro-Québec power grid, leaving six million people without electricity. A similar event today could destabilize entire regional grids, leading to blackouts lasting days or weeks, depending on the availability of replacement transformers.
A severe geomagnetic storm also disrupts satellite operations, affecting navigation and communications worldwide. Charged particles cause surface charging on satellites, leading to component failure or system reboots. Atmospheric changes interfere with GPS signals, causing timing errors and signal loss, which makes precise navigation for shipping, aviation, and financial systems unreliable. Furthermore, solar flares cause immediate High-Frequency (HF) radio blackouts, which are relied upon for long-distance communication by aviation and emergency services.
Planning for Extended Power Outages
Survival during an extreme space weather event requires preparing for a long-term loss of electricity and the services that rely on it. An emergency kit should include a minimum three-day supply of water (one gallon per person per day) and non-perishable food. Medications requiring refrigeration, such as insulin, should be stored in insulated containers with ice packs, and you should consult a pharmacist about short-term storage alternatives.
Financial security is a concern when the power grid is down, as ATMs, credit card readers, and digital banking services will be non-functional. Keep a reserve of physical cash in small denominations, hidden securely, to cover immediate needs like fuel or food from local vendors. Communication should also be planned, including establishing a family contact plan with an out-of-state point person who may have better access to functioning phone lines. A battery-powered or hand-crank radio is essential for receiving official updates from emergency authorities.
Heating and cooling without electricity requires low-tech strategies to maintain a safe indoor temperature. In cold weather, focus on heating a single room, utilizing passive measures like blocking windows with heavy curtains to retain heat. A well-insulated home may retain warmth for only six to ten hours. Portable propane heaters can be used for zone heating, but they must be properly vented and monitored to prevent carbon monoxide buildup. During hot weather, utilize passive cooling by shading windows during the day and opening them at night to allow cooler air to circulate.
Sanitation and hygiene are paramount to preventing the spread of illness during an extended outage. Without pressurized water, toilets will not flush, necessitating the storage of water for manual flushing or the use of a lined five-gallon bucket as a temporary commode. Stock hygiene supplies like bleach, which can be used to purify water or sanitize surfaces, and wet wipes to maintain personal cleanliness. Disposable plates and cutlery can significantly reduce the amount of water needed for washing dishes.
Monitoring Alerts and Taking Immediate Action
The official source for space weather alerts is the Space Weather Prediction Center (SWPC), part of the National Oceanic and Atmospheric Administration (NOAA). NOAA uses the G-scale, a five-level system (G1 to G5), to communicate the severity of a geomagnetic storm, with G5 representing an extreme event. Forecasters can often provide a warning of several hours to a few days, as the CME’s speed determines its arrival time.
When a severe geomagnetic storm warning is issued, immediate actions must be taken to protect personal technology. Unplug sensitive electronic devices and appliances from wall outlets, as power surges from GICs can bypass standard surge protectors and cause damage. This includes computers, televisions, and charging devices. Back up all critical digital data to an external drive or cloud service promptly before the event.
Transportation is another immediate concern, as fuel pumps rely on electricity and GPS navigation may become degraded or fail entirely. Keep vehicle fuel tanks at least half-full. If you rely on a garage for access, ensure you know the location and operation of the manual release lever for your electric garage door opener before the power fails.