Wednesday, 15 August 2012

Next Magnetic Pole Reversal Is Underway

A new study indicates that there is a possible connection between the Earth's inner core and a magnetic reversal. Peter Olson and Renaud Deguen of Johns Hopkins University in Baltimore, Maryland, used numerical modelling to establish that the axis of Earth's magnetic field lies in the growing hemisphere. Now the researchers speculate that there are signs that the next magnetic pole reversal may be underway The magnetic field reverses direction every few thousand years. While one side of Earth's solid inner core grows slightly, the other half melts, the scientists concluded in their research paper. If it happened now, we would be exposed to solar winds capable of knocking out global communications and power grids.

The rapid movements of the field's axis to the east in the last few hundred years could be a precursor to the north and south poles trading places, the researchers suggest. "We kind of speculate there is that connection but the chaos in the core is going to prevent us from making accurate predictions for a long time. "What we found that is interesting in our models is a correlation between these transient [shifts] and reversals [of Earth's magnetic field]," says Olson. "

Bruce Buffett of the University of California, Berkeley, says the authors present an intriguing proof of concept with their model. "They are suggesting very cautiously that maybe this rapid change is somehow suggestive of us going into a reversal event," he says.

"You could imagine if the field were to collapse it would have disastrous consequences for communication systems and power grids."

How Much Should We Fear Incoming Solar Activity?

Moreover, even with a weakened magnetic field, Earth's thick atmosphere also offers protection against the sun's incoming particles A weaker field would certainly lead to a small increase in solar radiation on Earth - as well as a beautiful display of aurora at lower latitudes -- but nothing deadly. But, while Earth's magnetic field can indeed weaken and strengthen over time, there is no indication that it has ever disappeared completely. According to NASA, it is a mistake to assume that a pole reversal would momentarily leave Earth without the magnetic field that protects us from solar flares and coronal mass ejections from the sun.

Movement of Earth's North Magnetic Pole Accelerating Rapidly

After some 400 years of relative stability, Earth's North Magnetic Pole has moved nearly 1,100 kilometers out into the Arctic Ocean during the last century and at its present rate could move from northern Canada to Siberia within the next half-century.

If that happens, Alaska may be in danger of losing one of its most stunning natural phenomena - the Northern Lights.

However, rapid movement of the magnetic pole doesn't necessarily mean that our planet is going through a large-scale change that would result in the reversal of the Earth's magnetic field. It may also be part of a normal oscillation. Calculations of the North Magnetic Pole's location from historical records goes back only about 400 years, while polar observations trace back to John Ross in 1838 at the west coast of Boothia Peninsula.

No Reason To Panic

Earth's magnetic field has flipped its polarity many times over the millennia and reversals are the rule, not the exception.

Earth has settled in the last 20 million years into a pattern of a pole reversal about every 200,000 to 300,000 years, although it has been more than twice that long since the last reversal. A reversal happens over hundreds or thousands of year, and not over night.

This means a magnetic pole reversal is not a sign of doomsday. 

No comments:

Post a Comment