The past six months have reportedly been weakening Earth's magnetic field, which protects the planet from huge blasts of deadly solar radiation, according to data collected by a European Space Agency (ESA) satellite array called Swarm. The cause is being investigated by scientists, Live Science reported.
The magnetic field, which extends 370,000 miles (600,000 kilometers) above the planet's surface, has witnessed the occurrence of weak spots over the Western Hemisphere, while areas like the southern Indian Ocean have experienced strengthening of the field, according to the magnetometers onboard the Swarm satellites - three separate satellites floating in tandem.
It has always been known by scientists that magnetic north shifts. "Once every few hundred thousand years the magnetic poles flip so that a compass would point south instead of north. While changes in magnetic field strength are part of this normal flipping cycle, data from Swarm have shown the field is starting to weaken faster than in the past," according to Live Science. "Previously, researchers estimated the field was weakening about 5 percent per century, but the new data revealed the field is actually weakening at 5 percent per decade, or 10 times faster than thought. As such, rather than the full flip occurring in about 2,000 years, as was predicted, the new data suggest it could happen sooner."
Although scientists who conducted the study remain unsure on why the magnetic field has been weakening, one likely cause could be that the Earth's magnetic poles are getting ready to flip, said Rune Floberghagen, the ESA's Swarm mission manager. In fact, the data suggest magnetic north is moving toward Siberia. "Such a flip is not instantaneous, but would take many hundred if not a few thousand years," Floberghagen told Live Science. "They have happened many times in the past."
Still, there is no evidence that a weakened magnetic field would result in a historic disaster for Earth since past polarity flips didn't cause any mass extinctions or show evidence of radiation damage. Instead, researchers believe that power grids and communication systems would be more at risk.
Meanwhile, Floberghagen hopes that more data from Swarm will shed light on why the field is weakening faster now. "The Swarm satellites not only pick up signals coming from the Earth's magnetic field, but also from its core, mantle, crust and oceans," Live Science reported. "Scientists at the ESA hope to use the data to make navigation systems that rely on the magnetic field, such as aircraft instruments, more accurate, improve earthquake predictions and pinpoint areas below the planet's surface that are rich in natural resources. Scientists think fluctuations in the magnetic field could help identify where continental plates are shifting and help predict earthquakes."
These first results from Swarm were presented at the Third Swarm Science Meeting in Denmark on June 19.