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

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

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