Metro Science: Pole reversal, the universal language and take a stand against sitting
Nothing ever stays the same. Including the location of the magnetic North Pole.
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DECODED: Pole-pocalypse soon
The ground may feel solid beneath your feet, but under the rocky surface layer, there’s turmoil brewing. The liquid metal roiling inside the earth – called the outer core – is a chaotic place. Its movement generates our planet’s magnetic field. And it's undergoing major changes. This might be because the North and South poles are starting to reverse positions, as they have done many times (The last was about 780,000 years ago). It won’t happen overnight; more like over millennia. But when it does, the impact on everything from navigation to radiation exposure could be huge. Alanna Mitchell, author of the new book The Spinning Magnet, explains.
The Earth’s core is on the fritz. What could happen?
The magnetic North Pole is the place where, if you stood with a 3D compass, the needle would point straight down. The geographic North Pole is the northernmost point on the planet. These two places are close together, but they’re not the same thing. Because of the Earth’s shifting magnetic fields, the magnetic North Pole is actually moving 55 kilometres to the north-northwest every year — breakneck speed in planetary terms. This could be the start of a true reversal of the poles, or just an aberration.
A pole reversal would vastly throw off the migration paths of whales, birds, and countless other species that navigate their way around the planet by way of magnetic fields (which birds can actually SEE: so cool!). Science suggests they’ll adapt – after all, they’ve done it before — but it’s more of a concern now because so many species are already in such dire straights because of human habitat destruction and climate change. Whether they have the resilience to handle this as well is an open question. Oh, and human compasses would certainly stop working.
If our planet’s poles really reverse, while they’re in transit the protective magnetic field that surrounds the Earth will weaken dramatically. Like the repelling side of a magnet, the field deflects all sorts of harmful radiation, including showers of particles from solar storms and cosmic radiation from outside our solar system. Without it, we’ll be exposed to much more UVB rays. Satellites (and therefore GPS) might fail. Parts of our infrastructure that conduct energy — like pipelines and electrical grids — might not withstand it.
There’s already a gigantic area of severely weakened magnetic field called the South Atlantic Anomaly. Mitchell likens it to a bruise on the apple of Earth. Covering a little more than 20 per cent of the planet, it stretches from southern Africa to western South America and south almost to Antarctica. When the Hubble Space Telescope and NASA’s MODIS satellite pass through, they are bombarded with so much radiation that their instruments stop working properly.
Scientists don’t know yet if a reversal is underway – but they know one will happen at some point, beyond a shadow of a doubt. If we start studying how it works now, our great-great-great-great-grandchildren will thank us.
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