Shifting poles
Scientists are baffled by a sudden, dramatic acceleration in the shift of the earth’s magnetic poles. They’re fearful not only of its impact on global navigation systems, but also for the entire planet’s well-being.
Something odd is going on with Earth’s Magnetic North Pole. No one’s exactly sure why it’s begun shifting very rapidly, but scientists are worried.
Every navigator knows that True North is different from Magnetic North. While the earth’s True North Pole lies atop the Arctic ice cap and is the axis around which the planet spins – a boat’s compass actually points to a point somewhere in the frozen wastes of the Canadian Arctic – about 500km away. The difference between True and Magnetic North is called variation and was first discovered by British explorer James Clark Ross in 1831.
The amount of variation differs across the planet. It’s roughly 20o around New Zealand but can be twice that in higher latitudes. Furthermore, Magnetic North is erratic and wanders constantly, changing very slightly every year. The annual rate of variation change is reflected on a navigation chart’s compass rose and needs to be factored into your course calculations. All very ho-hum.
But from the beginning of the 21st century (19 years ago) Pole ‘drift’ has been creating unease among those monitoring these things. Researchers have discovered that the pace of change in Magnetic North has accelerated significantly – it’s ‘skittering’ away from Canada, across the Pole, and heading towards Siberia.
“It’s moving at about 50 kilometres a year,” says Ciaran Beggan, a member of the British Geological Survey. “It didn’t move much between 1900 and 1980 but it’s really accelerated in the past 40 years.” The issue, he adds, is so severe that researchers are scrambling to update the widely-used World