- Did you know that there's weather in space?

More importantly, did you know that it can have a real effect on our lives here on earth?

Well, it can.

Over the next few years, we're heading into a solar maximum which means more chances to see beautiful Northern Lights but also large geomagnetic storms, which pose a threat to critical infrastructure.

US federal agencies estimate that the largest storms ever recorded could bring down the power grid for up to a year.

Yep, that's millions of Americans without power for an entire year.

Now it is possible to harden our grid against the threat, but, - If the wrong understanding of the geomagnetically induced currents was used, they might end up suggesting hardening some of these transformers, a very, very expensive process.

But what if they harden the wrong ones?

And they didn't harden the right ones?

(dramatic music) - [Maiya] Most of the time when an eruption happens on the surface of the sun, it leads to, at most, beautiful lights in the northern sky.

But if they're large enough, the geomagnetic storm an eruption creates can send devastating shock waves throughout our electrical system and impact other kinds of technology.

We saw this during the production of this episode when SpaceX lost 40 satellites, just after launch due to a relatively minor storm.

- The sun goes through an 11 year solar cycle, we call it, where the sun actually does a reversal of polarity.

During this process, we get big sun spot groups which produce big eruptions that can affect technology here on earth and in space.

That essentially is space weather.

So when we see an eruption on the sun we're talking about something very, very large.

The associated material that erupts out into space, it's called a coronal mass ejection.

And we're talking about a billion tons of plasma gas exploding out of the space with magnetic fields shot out into space sometimes towards the earth.

When it hits the earth, the earth has a magnetic field.

So we have two magnets essentially coming together.

The sun shot out a magnet.

It makes the 93 million mile transit from the sun to the earth, interacts with earths magnetic field, and there is a response.

We call it a geomagnetic storm or a geomagnetic disturbance.

And that's what creates the beautiful aurora borealis, and the aurora australis, the Northern Lights and the Southern Lights.

(fast piano music) - [Maiya] The next solar maximum will occur in 2025.

During the years around that peak we're more likely to experience large CMEs that could affect us here on earth.

- Here's how the more explosive coronal mass ejections happen.

First, flux ropes on the suns surface become too stressed and realign to relieve that stress.

This causes a sudden release of electromagnetic energy and an explosion of plasma away from the sun.

These geomagnetic storms caused blackouts across the entire province of Quebec in 1989, and much of South Africa in 2003.

Those were some of the strongest recent storms, but far from the strongest ever recorded.

- In 1859, we had what's called the Carrington Event.

It was one of the biggest flares, perhaps in the last 500 years.

Some of the work done has suggested that it's 3, 4, 5 times as big as the March of 1989 storm.

- [Maiya] When space weather impacts earth, one major effect is the creation of electrical currents in some of our most critical technological networks like power grids.

These are known as geomagnetically induced currents because they're caused by the changes that take place in Earth's magnetic field.

They don't affect humans, so we didn't know about them until we developed technologies that were disrupted by them.

- We've known since the middle of the 19th century about geomagnetically induced currents.

And that was back in the day when the high tech thing in the world was the telegraph network.

We're going way back here.

And one fine day, a day where there were auroras in the tropics, was a day were sparks coming out of many of the telegraph stations in the world, literally sparks were flying, and had nothing to do with the telegraph signal.

And people at that point were trying to understand what is going on?

There seems to be a connection between the sun and this strange phenomenon we've seen on the telegraph network.

Now, we get to more recent times, and in 2012, where we started to have good instrumentation in orbit and also out in deeper space, we saw a gigantic coronal mass ejection.

- The reason we didn't see any news on it, the reason we didn't have much in the way of impacts was because it missed us, we got lucky.

The sun, that big globe, 93 million miles away from us, there's only a window of about 40 degrees on a 360 degree ball.

I often reference it as the kill zone.

(fast piano music) - The ramifications of that would've been very serious because the grid now, that we depend on for essentially all of technological civilization, is more fragile than it's ever been.

- [Maiya] If we were hit by a CME as large as the 2012 event, life on earth would not immediately be at risk.

But some of our most relied upon technology would be.

- Had we had that event hit, the estimate is a substantial part of the American power grid would've gone down.

And had it gone down for a sustained period of time, keeping in mind, it takes a long time to get these replacement transformers, years.

Since absolutely all critical infrastructure, with only a few exceptions, depends on the power always being on, The ramifications were really significant.

- [Maiya] The United States power grid relies on approximately 2200 massive electrical transformers to distribute electricity throughout the country.

The system was built long before we had any real understanding of how induced currents from the sun, during these large storms would impact it - [Adam] You know, the biggest machine, arguably the biggest machine ever built, is a power grid.

Well, the power grid, you know, thousands and thousands of miles long, it's grounded to the earth.

And so when you get a big electric field set up in some section of the power grid and it's pointed in the right direction, you can set up magnetically induced currents in that section of the power grid.

And that affects the next section, and the next section, depending on what the electric fields are like.

And so when you start looking at, if I'm gonna mitigate risk, and I've got these incredibly expensive things, these giant transformers, every one of which is a custom build, right?

They're built for that circuit, and the lead time to get a replacement, may be two or three years.

You've got a real problem.

Where it gets really tricky, is when you enter a mode called cascading failure mode, and you start getting an affect of other transformers down the line going down.

- [Maiya] Some of these transformers across the country have already been prepared with solar storms in mind.

However, these preparations were made according to a simplistic understanding of our planet's conductivity, not actual observations of its electrical field.

Now this has important applications in terms of the effects solar storms will have on the power grid.

Adam, along with his team of geophysicists devised a comprehensive plan to systematically map the structure of the entire United States in 3D in order to better understand the electrical conductivity of the continent.

And what they found, deeply changes our understanding of how we can prepare for solar storms.

- What really is exciting, is very rarely do you get a chance to do frontier science.

And in this case, we're doing geological mapping.

And you might say, "Well, the United States has been geologically mapped for centuries, hasn't it?"

Well not in 3D.

And so this is getting us one of those very first maps in 3D of what the United States actually looks like to those depths - [Maiya] Using this map data combined with the actual location and orientation of electrical infrastructure, Adam and his team can run simulations that show how our grid will be affected in a major solar storm.

- It turns out that in some locations you can see an impact of maybe an order magnitude or even more deviation from what people had been doing by making more simple assumptions - [Maiya] Before Adam's work, it was assumed that the impact of solar storms would be stronger, closer to the poles because the Earth's magnetic field is stronger in those areas.

- When we add our information, that is how complex the geo electric structure is, we find the complexity of the geo electric structure is the dominant factor in how intense the geomagnetically induced currents are.

Not the intensity of the geomagnetic disturbance itself.

- [Maiya] To understand this, think of the earth as a circuit.

When an induced current flowing through it reaches areas where the conductivity of the earth's structure varies, voltage of that current changes, putting some of the nearby electrical infrastructure at far greater risk.

- It's the intensity of the variation in geo electric structure is dominant.

So even if you have a weaker geomagnetic disturbance, you can still get a really strong geomagnetic induced current.

- [Maiya] He found that some entirely unexpected regions are at risk.

Like the transition between the Appalachian mountains and the Eastern Seaboard as far south as Alabama and areas in the Midwest where rich iron deposits once supplied the US auto industry.

Both regions with large populations.

- It's no longer just that, as you go further south you have on average, less intense geomagnetic disturbances.

It's that how the earth works below it that really is providing some surprises.

- [Maiya] The good news is that with enough warning, the loss of life could be minimized and even the loss of power.

And you would see the most spectacular Northern Lights, even as far south as Florida and Texas.

There's not a lot we can do as individuals to prevent power loss, that will take big infrastructure investments.

But it's good to remember to prepare for power outages.