NASA has confirmed fears that recent weakening of the Earth's magnetic field indicates that we are soon going to see a reversal of Earth's magnetic poles that would cause compasses to point to the south instead of the north.
There are growing fears that weakening of the Earth's magnetic field and reversal of magnetic poles could have catastrophic consequences for humanity. Some experts believe that magnetic poles shifts in the past triggered mass extinctions, including extinction of Neanderthals.
NASA's MAVEN (Mars Atmosphere and Volatile Evolution) principal investigator Bruce Jakosky, with University of Colorado, Boulder, warned recently that there is evidence the Earth's magnetic field is weakening and that we would soon see a complete reversal of magnetic poles.
Scientific researchers say there is evidence that the Earth's magnetic field has weakened significantly in the past 160 years and that neutralization of the magnetic field and flipping of magnetic poles could occur in less than 1,000 years – or as early as the next 100 years.
Weakening of the Earth's magnetic field, caused by gradual reverse re-alignment of iron atoms in the Earth's liquid outer core, will lead to a reversal or flipping of Earth's magnetic poles so that compasses point to the south instead of the north.
According to Monika Korte with the Niemegk Geomagnetic Observatory at GFZ Potsdam, Germany, "It's not a sudden flip, but a slow process, during which the field strength becomes weak, very probably the field becomes more complex and might show more than two poles for a while, and then builds up in strength and [aligns] in the opposite direction."
"When the polar shift happens, the Earth will have no magnetic field for about 200 years," Jakosky said.
Weakening of the Earth's magnetic field could have serious consequences for life on Earth because the magnetic field acts as a shield that prevents dangerous solar radiation from passing into the atmosphere.
When its magnetic field is neutralized, the Earth will lose its ability to shield its atmosphere from direct exposure to dangerous solar radiation for up to 200 years, leaving humanity and life on Earth exposed to harmful radiation from the sun, including solar flares and coronal mass ejections (CMEs).
This would lead to a surge in the incidence of skin cancers, and disruption of power and communication, according to scientists.
Scientists believe that a shift in magnetic poles occurred 780,000 years ago. Some scientists say that another shift that occurred about 41,000 years ago, during the Ice Age, could have caused the extinction of the Neanderthals. Consequently, a shift in magnetic poles could threaten survival of humanity.
However, other experts dispute the alleged link between magnetic poles shifts and species extinction.
"Even if the field becomes very weak, at the Earth's surface we are shielded from radiation by the atmosphere," According to Korte. "Similarly as we cannot see or feel the presence of the geomagnetic field now, we most likely would not notice any significant change from a reversal."
Jakosky delivered the warning that we could soon see a flip of magnetic poles while announcing results of MAVEN measurements which show that Mars once had a thick atmosphere but that 99 percent of the atmosphere that could have supported life was stripped away by solar flares.Scientists believe that Mars once had a magnetic field but became more vulnerable to the atmosphere stripping effect of solar radiation and flares after it lost it.
According to John Grunsfeld, administrator for NASA Science Mission Directorate in Washington, "Mars appears to have had a thick atmosphere warm enough to support liquid water which is a key ingredient and medium for life as we currently know it. Understanding what happened to the Mars atmosphere will inform our knowledge of the dynamics and evolution of any planetary atmosphere."
A magnetic pole shift that neutralizes Earth's magnetic field and leaves it exposed to solar radiation would initiate the process by which solar winds stripped Mars of its atmosphere. However, the stripping of Mars' atmosphere by blasts of solar winds occurred over billions of years. Because the Earth is expected to experience a magnetic poles shift for only 200 years, scientists believe that the Earth will not lose enough of its atmosphere to cause extinction of life.
Michael Myer, scientist with the NASA Mars mission, explained that when our solar system was young, the sun was much more active and thus Mars was subjected to more powerful blasts of solar flares that quickened the rate at which its atmosphere was stripped away.But despite the fact that 200 years is not enough to cause the Earth to lose a significant part of its atmosphere to solar wind, a magnetic poles shift could still have serious consequences for humanity. Reversal of the Earth's magnetic field will deprive life on Earth of the benefit of magnetic shield and expose us to dangerous radiations such as ultraviolet radiation leading to an increase in skin cancers.
Exposure to solar radiation could also make power grids and electronic communications systems more vulnerable to disruption.
However, scientists have tried to allay fears caused by predictions by some doomsday theorists that a flip of the magnetic poles could shift the continents and trigger earthquakes, tsunamis and catastrophic changes in global climate.
Express reports that Alan Thompson, with the British Geological Survey, said there is no evidence from geological and fossil records that previous poles shift caused "shifting of continents or other planet-wide disasters."
[Image via NASA/Wikimedia]