Gap Fill - Magnetic Poles - Level 6

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   ago      beach      considerable      creatures      crust      effects      gigantic      grids      merchants      polar      potential      radiation      radiation      rates      responsible      rolling      satellite      strikes      threats      years  
When doom-and-gloom warn us about to our existence, we usually hear about climate change, asteroid or nuclear war. Now scientists have warned of the threat from Earth's magnetic poles flipping upside down. The North Pole and South Pole are for creating a special barrier around Earth that protects us from killer from space. All life on Earth depends on this shield. Without it, scientists say solar rays could cause damage. The poles could flip in the next thousand years. This is because a layer of liquid iron under the earth's is changing direction. The revolving currents of this molten iron at Earth's center act as a electromagnet.

Historically, Earth's North and South magnetic poles have flipped every 200,000 to 300,000 . The last time was 780,000 years , so the next flip is well overdue. Some scientists say the flip could destroy communications and power ; that dangerous solar rays would greatly multiply of cancer; and that climate change could kill billions of . Some scientists forewarn that a flip could even blow Earth's atmosphere away. However, one scientist dismissed the doom-mongers. He believes that the of any increase in radiation would be as harmful as lying on a hot for a day. He suggested a "floppy hat" would be enough to protect us from any increased .

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