Name: Earth’s Magnetic North Pole Is Shifting South… So What Now?
Uploaded: 2020-03-28T10:01:48.000Z
Duration: 4 min 35 s
Description: Thousands of YouTube videos with English-Chinese subtitles! Now you can learn to understand native speakers, expand your vocabulary, and improve your pronunciation...

The subjunctive

You may have heard that the earth’s magnetic poles tend to move around.

I mean, so do the geographic poles, but magnetic North and South are really mobile...and magnetic

Like, way faster than we thought it would.

And the scientific community is coming up with some really exciting and creative ways

The prevailing theory about why our planet has a magnetic field in the first place is

because of what’s underneath the crust.

Dynamo theory, as it’s called, is the idea that the molten metals of the outer core,

like iron are being convected—basically, swirled—all around the Earth’s interior,

This continuously creates electric currents as charged particles move through this liquid

metal, and—in combination with the rotation of the Earth—becomes what’s called a dynamo:

This also explains why the magnetic poles are not necessarily fixed points, because

the liquid that creates the magnetic field is turbulent, and always shifting, the poles

move as the fluid does. Right now, for instance, the North magnetic Pole has been slipping

down into Siberia for the past 150 years or so...and it’s speeding up.

Our magnetic field actually has a name. It's called the magnetosphere and it plays a crucial role

It wards off much of space’s harmful radiation like cosmic rays, acting like an essential

Which is one reason why scientists and governments are so invested in knowing how it works and how

Like with the World Magnetic Model, for example.

This huge and innovative computer model of Earth’s magnetic field behavior is used

by many international bodies as the guiding standard on what the world’s magnetic field

It combines sensor measurements of the field’s strength and position, measurements which

are then used in simulations of the geodynamo’s past, present, and future behavior.

The WMM releases updates to the model every five years, but in 2019, it was forced to

release a mid-cycle update because magnetic North has been sauntering vaguely downwards

much faster than anticipated...the perfect example of the fact that even though we’re

measuring and predicting to the best of our abilities, the geodynamo is too unpredictable

and complex to make a truly complete model of it.

That uncertainty means scientists are also looking for experimental ways to further probe

the Earth’s magnetic behavior, which typically involves creating models of the Earth out

Which is quite the commitment, because sodium is a highly reactive metal that is extremely

difficult to handle and likes to spontaneously burst into flame.

New sodium ball experiments are being used in several labs worldwide, and—in combination

with improvements in computing and machine learning—could help us gain more insight

into how Earth’s magnetic field will change...and how we could prepare for when it does.

Because what does a shifting magnetic field actually mean for us?

Flipped poles would mean that the names of Earth’s hemispheres may be a bit confused

for a while, and compasses would point in the opposite direction than they did previously.

But more importantly, as the poles shift around, the magnetosphere could get weaker, with several

smaller magnetic poles popping up in other places around Earth.

A weakened magnetosphere means many things: the Northern lights will be visible in new

All our satellites would need to be extra fortified against radiation, or we risk them

getting totally fried by space weather like solar wind.

Electronics here on Earth would be extremely vulnerable to interference and destruction

by space radiation too, like our power grids.

And that’s not even mentioning the human health effects of being exposed to much higher

degrees of radiation from space, which let me tell you, are not great.

We know from studying magnetic inclusions that Earth’s magnetic field has flipped

entirely in the past— they trade places about every 300,000 years, or so but it’s

been over double that since the last time we know they flipped.

So we are long overdue for some magnetic migration and it’s happening...fast.

And scientists are working hard to understand why and how they move and what exactly it

The next update to the WMM is expected in early 2020.

Do you want to know more about it when it comes out?

Make sure you subscribe to Seeker for all your science news, and for more on surprising

things inside the planet, check out this video here.

As always—thanks for watching, and we’ll see ya next time.