There is an invisible force field that surrounds the whole planet Earth. It guards life on Earth from harmful solar radiation by deflecting charged particles away. Every once in a while, this field shifts.

Do you know what would happen to us when the Earth's magnetic shift swaps places again?

This reversal occurs a few times in a million years on average. It would make the magnetic field turn to a weaker and more complex form, possibly falling to 10 percent of its present strength. 

Brunhes-Matuyama, the last known full reversal, happened 780,000 years ago. A temporary reversal lasted less than 1,000 years when it occurred around 41,000 years ago - called the Laschamp event.

Effects: Power cut or mass extinction?

Since the alteration will weaken the power of the force to shield us from harmful radiants, there would be risks for satellites, aviation, and ground-based electrical infrastructure. Chances of Geomagnetic storms, driven by the interaction of anomalously large eruptions of solar energy with our magnetic field, can also be expected due to the debilitation.

The Earth's terms of life vary so the direct impact of a reversal on our species is unpredictable. Modern humans did not exist during the time of last full reversal.

Studies have been conducted in hopes of linking the past reversals to mass extinctions. Researchers have suggested that these episodes could be driven by a common cause. Still, at this point, there is no evidence.

Can we predict geomagnetic reversals?

As a matter of fact, scientists have observed that we are "overdue" for a full reversal and the Earth's field is currently decreasing at a rate of 5 percent per century. This has led to speculations that the field may reverse within the next 2,000 years.

Giving the precise date would be a hard task since the Earth's magnetic field is generated inside the liquid core. Just like the atmosphere and oceans, the process is governed by the laws of physics. If we track this movement, we can be able to sense the "weather of the core."

There are hardships in predicting the weather even with direct observations. For the Earth's core, this is a far more difficult prospect, principally because it is buried beneath 3,000km of rock such making it scant.

Even so, we are not blind: we are aware of the major composition of the material inside the core and that it is liquid. A global network of ground-based observatories and orbiting satellites also measure how the magnetic field is changing.

A recent discovery made using jet-stream within the Earth's core highlights our evolving ingenuity and increasing ability to measure and depict the dynamics of the core. Combined with numerical simulations and laboratory experiments to study the fluid dynamics of the planet's interior, our understanding is gradually developing

The possibility of forecasting the state of the Earth's core might just be achievable soon.