Magnetic north is moving so fast it’s defying predictions and ruining maps. CIARAN BEGGAN of the British Geological Survey brings us up to speed.
WHY DOES THE MAGNETIC NORTH POLE MOVE, AND WHY IS IT MOVING SO QUICKLY?
The magnetic field is created by the liquid outer core that starts about halfway to the centre of the Earth. You’ve got this large, convecting layer of liquid metal and, as it moves, it creates the magnetic field, but it also drags the field with it. The reason the magnetic north pole is moving is because, we think, a fast jet of liquid has formed – a sort of jet stream – at the high latitudes up around northern Canada, and it’s pushing the magnetic field in this area rapidly. If you look back at how the magnetic north pole has moved in the last hundred years or so, you’ll see that from 1900 to 1990the average rate of change of the pole’s position was about 5 to 10 kilometres per year, and in the 1990s it suddenly started accelerating. At the moment, it’s moving at about 50 or 60 kilometres per year.
HOW’S THAT GOING TO AFFECT THE AVERAGE PERSON?
로그인 및 구독신청 후 이용해주세요.