The Earth's geographic poles are moving faster than previously thought, according to a study published in the journal Science. Researchers found that the northern and southern extremities of the Earth have experienced particularly rapid movements in the past, with displacement speeds exceeding approximately 0.6 degrees per million years. This rate is much faster than the movement of most tectonic plates. The phenomenon results from mantle convection, a thermal process inside the Earth responsible for the movement of tectonic plates. When the planet's rotation is disturbed, the outer layers of the globe move in order to regain a rotational balance, displacing the two poles. The study, reported by New Scientist, used geological archives of sea level variations to detect signals that could appear during true polar displacements. During these episodes, sea level rises in one half of the hemisphere and decreases in the other half, creating a symmetrical pattern that is not caused by other terrestrial processes. By observing historical variations in water levels, scientists discovered that spectacular displacements had occurred four times, 20, 90, 140, and 190 million years ago. These events spanned periods of about 10 million years. The Earth has two types of poles: the geographic ones, where the imaginary axis of rotation is located, and the magnetic ones, which result from its magnetic field. The magnetic poles are constantly in motion and often located hundreds of kilometers away from the North and South Poles. Sometimes, they even reverse. In comparison, the geographic extremities are much more stable, although they are not entirely stationary. Evidence of polar movements previously came from ancient magnetic data extracted from rocks formed millions of years ago. However, the results regarding the frequency and magnitude of these events were confusing and contradictory. The Norwegian researchers changed their method to examine the geological archives of sea level variations. The study was conducted by Mathew Domeier, a geography researcher at the University of Oslo in Norway. He explained that the crust and the mantle slide over the core during a polar drift episode. The strange symmetry between the northern and southern hemispheres of the Earth is disappearing, and these events, while imperceptible to humans, have significant impacts on climate systems over longer geological periods.