Thursday, October 31, 2019
Earth's Magnetic Pole Reversals Essay Example | Topics and Well Written Essays - 1000 words
Earth's Magnetic Pole Reversals - Essay Example ââ¬Å"In 2005, the North Magnetic Pole (NMP) was about 810 km (503 miles) from the Geographic North Pole. The NMP was in theà Arctic Oceanà north of Canada. The South Magnetic Pole (SMP) was about 2,826 km (1,756 miles) from the Geographic South Pole. The SMP was off the coast ofà Antarcticaà in the direction of Australiaâ⬠(Russel). The presence of earthââ¬â¢s magnetic field can be explained through the dynamo effect. Deep inside the earthââ¬â¢s core is a solid iron ball with temperatures reaching as high as that on the sun. This inner core is surrounded by a molten mass of iron, called the outer core. The molten mass of iron circulates relative to the motion of the earth. Convection currents within this region generate our planetââ¬â¢s magnetism (Phillip). Over years, many scientists have proven that the earthââ¬â¢s magnetic field is changing. James Ross located the pole for the first time in 1831 after an exhausting journey during which his ship got stuck. No one retrieved it until four years and when they did, they noticed that the pole had shifted from its original position, even though by a small amount. The next observation occurred in 1904 when Ronal Amundsen found the pole again and discovered that it had moved almost fifty kilometers since the days of Ross. This movement of the magnetic poles has hastened in the recent past. ââ¬Å"The pole kept going during the 20th century, north at an average speed of 10 km per year, lately accelerating to 40 km per year (Phillip). This sparked interest of researchers to study this phenomenon in detail. It has been discovered that iron and other heavy metals, present inside molten lave, align themselves in the direction of the external magnetic field when solidifying to form hardened rock. By studying the various layers of these rocks, scientists have measured the historical directions of the Earthââ¬â¢s magnetic field and concluded that the Earthââ¬â¢s poles
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