Data collected by the Swarm satellites reveals that the Earths magnetic field has changed significantly during the past six months. Over the past six months, the Earths magnetic field has been weakening 10 times faster than in previous years, reports the European Space Agency (ESA). The recent changes may indicate that the Earth's magnetic poles are about to flip. The magnetic field, which has been described as a huge bubble that protects the Earth from incoming cosmic radiation and solar winds, is always changing and ESAs Swarm mission has been tracking these fluctuations since November 2013. The magnetic poles flip every few hundred thousand years and changes in the strength of the magnetic field are part of the cycle, but what is striking is the rate at which it is weakening. Researchers estimated the field was weakening about 5 percent per century, but new data revealed the field is actually weakening at 5 percent per decade, or 10 times faster than thought, explains Kelly Dickerson at LiveScience. Scientists expect the next flip in about 2,000 years, but at this rate it may happen sooner. What does it mean for humans? Compasses could point south instead of north for the first time in more than a hundred thousand years, and grids and communication may be affected. According to LiveScience, the biggest weak spots in the magnetic field have been found over the Western Hemisphere, but it has strengthened over the southern Indian Ocean since January 2014. The latest measurements, as ESA states in a news release, suggest the movement of the magnetic North towards Siberia. Over the next few months, researchers will continue to analyse Swarms data to see how the mantle, crust, oceans, ionosphere and magnetosphere may be contributing to these change.
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