You've probably heard the term "EMP" thrown around in prepping circles. Maybe in a movie. Maybe from someone who sounded a little... intense about it. đ But what actually IS an electromagnetic pulse? And should we care?
So What Is an EMP?
Think of it like a giant invisible wave of energy that messes with electronics.
An EMP is a burst of electromagnetic radiationâbasically a huge surge of energy that travels through the air. When this wave hits wires, circuits, or anything electronic, it creates a massive spike of electricity inside them. Way more than they're designed to handle.
Here's the tricky part: It happens FAST. We're talking nanosecondsâbillionths of a second. That's way too quick for your surge protector to even notice, let alone respond.
Imagine if someone dumped a swimming pool's worth of water through your garden hose in one second. That's kind of what an EMP does to electronics.
Where Does an EMP Come From?
Two main sources. One is natural, one is... not.
âď¸ 1. The Sun (Coronal Mass Ejections)
Every once in a while, the sun basically sneezesâand a LOT of charged particles come flying toward Earth. Scientists call these coronal mass ejections, or CMEs.
When that cloud of solar particles hits Earth's magnetic field, it can induce massive electrical currents in anything long and conductive. Power lines. Pipelines. The grid.
This isn't science fiction. It's happened before.
The Carrington Event (1859) â This is the big one, named after Richard Carrington, a British astronomer who happened to be sketching sunspots when he saw an enormous solar flare. Nobody had ever recorded one before. The next day, all heck broke loose.
Telegraph systemsâthe internet of the 1800sâwent haywire. Operators got shocked. Equipment caught fire. Some telegraph machines kept working AFTER being unplugged, running on the current being induced by the storm. Aurora borealis was visible all the way down to Cuba and Hawaii. People in New England could read newspapers outside at night by the glow.
So why do we care about something from 1859?
If a Carrington-Sized Event Happened Today
Lloyd's of London projects $0.6 to 2.6 TRILLION in damages to the U.S. alone.
The National Academies estimates 20-40 million people could lose power for weeks to potentially yearsâbecause large transformers take 12-24 months to manufacture and there aren't many spares sitting around.
More Recent Events:
- 1989 Quebec blackout: A moderate solar storm knocked out the entire provincial power grid in 90 seconds. Six million people without electricity for 9 hours.
- July 2012: A Carrington-class CME missed Earth by about 9 days in our orbit. NASA said it would have been catastrophic if it had hit us directly.
- May 2024: Multiple CMEs hit Earth over several daysâpossibly the strongest solar storm of this century. (You might have seen the amazing aurora photos on social media!)
Solar events WILL happen. The question is just when and how intense.
â˘ď¸ 2. Nuclear EMP (The Scary One)
A nuclear weapon detonated high in the atmosphereâwe're talking 20-300 miles upâcreates an electromagnetic pulse that can affect an entire continent.
Here's the physics in plain English: when a nuclear weapon explodes at high altitude, the gamma radiation hits the upper atmosphere and knocks electrons loose from air molecules. These electrons start moving at over 90% the speed of light (yes, really), and this creates an enormous electromagnetic field that radiates downward.
A single detonation about 200 miles over Kansas could affect the entire continental United States.
We know this works because we accidentally proved it in 1962. The Starfish Prime test detonated a nuclear weapon 250 miles over the Pacific Ocean. It damaged electrical equipment in Hawaiiânearly 900 miles away. Streetlights went dark. Burglar alarms went off. A microwave communication link was damaged.
And that was 1962. Before everything had microchips in it.
The Three Phases (Quick Version)
A nuclear EMP actually has three components, and they matter for understanding protection:
E1 (The Fast One)
The nanosecond burst that fries electronics. Travels through the AIR as a wave and induces current directly into circuits. Your surge protector can't respond fast enough.
E2 (The Middle One)
Similar to a lightning strike. Most surge protectors can handle this part.
E3 (The Slow One): This one lasts seconds to minutes and damages the power grid itselfâsame mechanism as solar storms. This is what takes out transformers.
High Altitude vs. Ground LevelâWhy It Matters
If a nuclear weapon explodes near the ground, yes there's EMP, but honestly... the blast and radiation are your bigger immediate problems.
High-altitude detonations are different. The EMP spreads over a HUGE area, but there's no direct blast damage to people on the ground. That's what makes it a distinct kind of threatâit can take out infrastructure across multiple states without a mushroom cloud over any city.
"But How Likely IS This?"
Fair question. Here's what the government says.
CISA (that's the Cybersecurity and Infrastructure Security Agencyâbasically the folks responsible for protecting critical infrastructure) puts it this way:
A nuclear EMP attack from a country with basic capabilities would be "disruptive on a regional scale but unlikely to cause catastrophic damage on a continental scale."
Countries with advanced nuclear capabilities could cause "widespread harm in the context of an escalating international conflict."
Translation: Solar events are guaranteed to happenâwe just don't know when. Nuclear EMP would most likely only occur as part of a larger war. But even small countries could potentially cause serious regional damage.
One More Thing: Why "Weather Balloons" Come Up
You might remember the Chinese surveillance balloon that crossed the entire continental U.S. in early 2023âflying over our ICBM installations before being shot down.
Did You Know?
The original high-altitude nuclear tests in the 1950s used weather balloons to lift the weapons to altitude. Congressional testimony from DHS notes that a nuclear EMP can be delivered by missile, satellite, or "a relatively low-cost balloon-borne vehicle."
We're not saying that balloon was carrying anything scary. But it's worth understanding why the military took it so seriously.
The Bottom Line
âď¸ Solar Events
Certain to happen, just a matter of when and how big.
â˘ď¸ Nuclear EMP
Less likely, but would be catastrophicâmost realistic in the context of broader international conflict.
Either way, understanding what we're dealing with helps us prepare intelligently.
Still with us? đ
We know that was a lot. But we think understanding the "what" and "why" matters before we talk about protection.
Because here's the thingâthere's a LOT of marketing out there for EMP protection products. Some of it is legitimate. Some of it is... well, we have thoughts. And we'd rather you understand the basics so you can evaluate products for yourself.
More coming on what protection actually worksâand where you can save some money by understanding the physics before you buy.
Key Takeaway
Solar events are guaranteed to happen. Nuclear EMP is less likely but possible. Either way, the prep approach is similar: protected backup power, non-grid communications, and enough supplies to weather an extended grid-down scenario.
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