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Earth’s magnetic pole is on the move, fast. And we don’t know why

Jamie Seidel, January 29, 2019 2:45PM News Corp Australia Network

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The magnetic North Pole is moving faster than expected, which means the navigational models that help us know where we are and where we are going are becoming dangerously inaccurate. media_cameraThe magnetic North Pole is moving faster than expected, which means the navigational models that help us know where we are and where we are going are becoming dangerously inaccurate.

geography

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Earth’s magnetic North Pole isn’t behaving how scientists expected.

According to the science journal Nature, the magnetic North Pole is rushing away from Canada, towards Siberia.

This means the navigational* models based on where the magnetic poles are — that we all use to know where we are and where we are going — are becoming dangerously inaccurate.

MAGNETIC POLES
Imagine the Earth has a big magnetic bar running through it. The magnetic north and south poles are located at the north and south ends of the big bar. There isn’t really a big magnetic bar, but there are massive rivers of hot, molten iron deep below the surface of the Earth that act like a magnet to create the Earth’s magnetic field. They also determine where the magnetic North Pole and magnetic South Pole are located.

A compass works to show us where north is because the needle has a magnet attached to it that is effected by the Earth’s magnetic field.

A compass helps us follow a map and find our way when we’re in the bush. media_cameraA compass helps us follow a map and find our way when we’re in the bush.

The magnetic field is necessary for our survival on Earth. It deflects* harmful radiation* from space and keeps Earth’s water and atmosphere* in place.

Earth has lines of magnetic force looping from North Pole to South Pole, creating Earth's protective magnetic field. media_cameraEarth has lines of magnetic force looping from North Pole to South Pole, creating Earth’s protective magnetic field.


FASTER THAN EXPECTED
“The magnetic pole is moving so quickly that it has forced the world’s geomagnetism* experts into a rare move,” Nature reports.

The World Magnetic Model — which runs modern navigation systems such as Google Maps — will soon get an urgent update.

This model is a necessary part of systems used by ships to navigate and by us in cars and on smartphones to know where we are and where we are going.

The current model was expected to be accurate until 2020. But the magnetic pole began to shift so quickly, scientists realised in 2018 that the model had to be fixed — now.

“They realised that it was so inaccurate that it was about to exceed* the acceptable (safe) limit for navigational errors,” Nature reports.

It could be dangerous if planes and ships, in particular, are navigating using a model that is really inaccurate.

Every year, geophysicists* from the US National Oceanic and Atmospheric Administration (NOAA) and the British Geological Survey check how the Earth’s magnetic field is varying.

This is necessary as the liquid iron churning in the Earth’s core does not move in a consistent*, predictable way.

“In 2016, for instance, part of the magnetic field temporarily accelerated deep under northern South America and the eastern Pacific Ocean,” Nature reports.

This shift was observed by satellites.

Satellites in space observe how the Earth’s magnetic field shifts. Picture: iStock media_cameraSatellites in space observe how the Earth’s magnetic field shifts. Picture: iStock

The movement of the magnetic North Pole has been studied since 1831. In the beginning, it was tracked moving into the Arctic Ocean at a rate of about 15km each year. But, since the mid-1990s, it has sped up.

It’s now shifting about 55km a year.

Why the magnetic field is shifting so dramatically is unknown.

“Geomagnetic pulses, like the one that happened in 2016, might be traced back to ‘hydromagnetic’ waves arising from deep in the core,” Nature reports. “And the fast motion of the north magnetic pole could be linked to a high-speed jet of liquid iron beneath Canada”.

This fast-flowing molten river appears to be weakening the magnetic influence of the iron core beneath North America.

Fast-flowing rivers of molten iron under the surface of the Earth create the Earth’s magnetic field. Picture: Getty Images media_cameraFast-flowing rivers of molten iron under the surface of the Earth create the Earth’s magnetic field. Picture: Getty Images


GEOGRAPHIC POLES
Earth also has geographic north and south poles. Imagine a massive axis or rod passing through the centre of Earth from the north to the south geographic poles. The Earth spins in space on this imaginary axis or rod.

These geographic poles are near, but not exactly in the same place as the magnetic north and south poles.

The Earth, looking straight at Antarctica. The geographic South Pole is on Antarctica. At the moment, the magnetic South Pole is off the coast off Antarctica. media_cameraThe Earth, looking straight at Antarctica. The geographic South Pole is on Antarctica. At the moment, the magnetic South Pole is off the coast off Antarctica.

GLOSSARY

  • navigational: used for finding the way
  • deflects: causes something to change direction and move away
  • radiation: energy sent out from something
  • atmosphere: the layer of gases around Earth and other planets
  • geomagnetism: science to do with the magnetic properties of Earth
  • exceed: go above or beyond
  • geophysicists: scientists studying the energy of the Earth
  • consistent: the same all the time

EXTRA READING

What is at the centre of the Earth?

How we tell the time just got more accurate

What is hidden under Earth’s crust?

Australia’s move north causing earthquakes

QUICK QUIZ

  1. What is the name of the science journal reporting this?
  2. Where is the magnetic North Pole rushing away from and towards?
  3. What does the Earth’s magnetic field do?
  4. How fast is the magnetic North Pole shifting now?
  5. What is the other type of poles mentioned? Are they in the same spot as the magnetic poles?

LISTEN TO THIS STORY


CLASSROOM ACTIVITIES
1. Navigation Errors
Divide a blank page into three columns. Write SHIPS, AEROPLANES and CARS at the top of the three columns. Work with a partner and make a list of the possible problems that could occur if the World Magnetic Model is more than a little inaccurate for the following three modes of transport.

Time: allow 20 minutes to complete this activity
Curriculum Links: English, Geography, Personal and Social

2. Extension
Draw a diagram to explain the difference between the magnetic north and south poles and the geographic north and south poles. Label your diagram and write a one paragraph description using your own words.

Time: allow 20 minutes to complete this activity
Curriculum Links: Geography, Science

VCOP ACTIVITY
With a partner see if you can you identify all the doing words/verbs in this text. Highlight them in yellow and then make a list of them all down your page. Now see if you and your partner can come up with a synonym for the chosen verb. Make sure it still makes sense in the context it was taken from.

Try to replace some of the original verbs with your synonyms and discuss if any are better and why.

HAVE YOUR SAY: Have you used GPS navigation, such as Google Maps? Did it work? How did it help you? What could have happened if it wasn’t accurate?
No one-word answers. Use full sentences to explain your thinking.

Extra Reading in geography