The dynamic magnetic field of our planet can change direction much faster than scientists thought
This bubble of magnetism, which we call the planet’s magnetic field, holds our atmosphere in place and protects us from harmful cosmic radiation and solar winds. But several times every millions of years the field polarity changes, and the magnetic north and south poles change places. The last time this happened was about 780,000 years ago, and previously it was assumed that the process takes thousands of years, shifting at a speed of about one degree per year.
However, it turned out that significant changes in the direction of the magnetic field can occur 10 times faster than expected, and almost 100 times faster than the recent observed changes, says lead author of the study Christopher Davies from Leeds University.
According to him, when the liquid core of the planets “boils”, this movement creates ups and downs of magnetic force in different parts of the core, which, in turn, determines how these areas affect the magnetosphere. In fact, recent observations show that the magnetic field has decreased over the past 160 years, suggesting that the Earth could survive a magnetic revolution earlier than estimated time.