Scientists Leeds and the universities of California in San Diego found that changes in the direction of Earth’s magnetic field may occur 10 times faster than previously thought. This was reported in an article published in the journal Nature Communications.
the Researchers analyzed data on changes of Earth’s magnetic field over the past 100 thousand years and combined them with a model of field generation. It turned out that the fast changes are associated with a local weakening of the magnetic field. This indicates that changes occur or when the field changed polarity, or when the axis of the dipole moved away from the geographical poles. For example, 39 thousand years ago the geomagnetic field was shifted by 2.5 degrees, which was accompanied by a weakening of the field strength off the West coast of Central America.
it was thought that the maximum displacement speed of the magnetic field is one degree per year, but, according to new data, the speed may reach a record ten degrees per year, which is a hundred times faster the current changes.
the Magnetic field due to the convection flows of the molten metal in the outer core of the Earth. As shown by the simulation results, the most rapid changes are associated with the occurrence of areas where the metal flow is directed in the opposite direction. These spots often form in low latitudes, and this allows scientists to narrow down the search for evidence of field change.
