New satellite data from the European Space Agency has revealed some puzzling findings: the Earth’s magnetic field appears to be weakening much faster than previous research would suggest. These measurements show that on the whole, the planet’s geomagnetic field is weakening about ten times faster than expected, at a rate of about 5% every decade. However, it’s also important to note that in some regions it’s actually strengthened, particularly over Asia.
The data was collected by the ESA‘s three Swarm satellites, which track changes in the Earth’s magnetic field, making note of the strength, direction, and variations across the globe. Since their launch in 2013, they’ve measured magnetic signals from the Earth’s core, mantle, crust, oceans, ionosphere, and magnetosphere – creating a much more detailed map than scientists have ever been able to create before.
The localized fluctuations in the magnetic field are easily explained; researchers believe that they’re due to the movement of liquid metal flowing within the planet’s core. What they aren’t yet able to explain is exactly why the field as a whole is becoming weaker, or what the effects of that change will be.
One possibility is that the changes indicate a coming reversal of the Earth’s magnetic poles, which scientists believe should occur roughly every 200,000 to 300,000 years. While such an event has long been fodder for doomsday prognosticators, geological and fossil records seem to indicate there are no lasting ramifications for life as we know it. Most of these relate to the fact that as the magnetic field weakens, it reduces the Earth’s built-in protection against solar radiation. However, NASA notes that there is no evidence this magnetic shield has ever disappeared completely.
Though the new findings may not indicate any coming danger, a change in magnetic poles will not be a swift or simple one: as the field morphs and shifts, multiple poles may emerge in odd latitudes around the planet over the course of hundreds, or even thousands, of years. Needless to say, this could prove to be a sticky issue for compass-based navigation, power grids, and communication systems, but it wouldn’t be an apocalyptic event.
Via Boing Boing
Images via ESA