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Magnetic north is moving

| January 28, 2019 12:00 AM

Our Earth’s geomagnetic field, also known simply as the planet’s magnetic field, protects us from the solar winds and deadly cosmic rays that would severely damage or destroy the ozone layer that shields our planet from ultraviolet radiation. Without the Earth’s magnetic field, there would likely be very little, if any, life on the planet as a large part of the atmosphere would be lost.

Scientists believe that this magnetic field is generated from deep within the Earth. It surrounds our planet and extends out into space. The spinning of the Earth generates a force, which is called the Coriolis force, that causes the liquid iron far below the surface to swirl and generate our magnetic field.

If you have a magnetic compass and stand to the north, the compass will point to “magnetic north.” However, Earth’s magnetic north is not the same as “true” north. In North America, the magnetic north pole has been moving away from Canada and into the Arctic Ocean. It’s a difference of just over 300 miles from Earth’s actual North Pole. By the way, since opposite magnetic poles attract, the North Magnetic Pole where the compass points to is really the south pole of its magnetic field.

The Earth’s magnetic field has been a vital navigation tool for aircrafts, smartphones and other equipment. Over time, our planet’s magnetic pole has shifted, but very slowly. The World Magnetic Model keeps track of the movements to the magnetic poles so adjustments can be made to navigation systems. The models that are created are supposedly good for 5 years, but the increased drift has forced a new update for the World Magnetic Model at the end of the month.

The movement of the magnetic pole in the north has been increased its speed from less than 10 miles per year prior to the mid-1990s, to nearly 35 miles per year. In 2001, the magnetic north pole entered the Arctic Ocean and crossed the International Date Line into the Eastern Hemisphere last year and is now heading toward Siberia. By the way, the magnetic field at the South Pole has been mostly stable.

The increase of the drift of the magnetic pole has also led to recent changes in the naming of airport runways as many are labeled based upon the compass points. Most runways are named in 10-degree increments and the drift of magnetic north has forced the change.

According to an article in Nature, the increased movement of the pole may be due, at least in part, to shifts of the liquid in the Earth’s core that generates much of the magnetic field. The article states that in 2016, there was an acceleration of the magnetic field under northern South America and the eastern Pacific Ocean.

Geologic history of our planet’s rocks does indicate that there have been a “swap” of magnetic north and south about every 200,000 to 300,000 years. But the last major one, according to a feature in National Geographic, occurred about 780,000 years ago. The process of the changing of magnetic north to south and vice versa is estimated to take place over thousands of years. There have been instances when the reversal occurred in hundreds of years.

One of the big questions is what will happen to life on Earth when the next reversal occurs? Most scientists believe that life will go on without any issues. The only main concern would be a weakening of the magnetic field to allow in more harmful ultraviolet radiation. It may also be tough for animals, like pigeons and wales, who depend on the magnetic poles for their directions. But, most think the creatures will adapt over time. Although there are websites calling for doom with this scenario, I wouldn’t lose any sleep over it.

In terms of our local weather, the 7.7 inches of snow measured last Tuesday night and Wednesday was the biggest snowstorm in the region since Feb. 16-17 of last year. Cliff said that it snowed for 14 straight hours and took the seasonal snowfall total to just over 31 inches in Coeur d’Alene.

As we move into February, we still see a rain and snow pattern across the region. Cliff and I expected about another 20 inches of snow in Coeur d’Alene in February, March and April which would end our season at a below normal 50 inches. It’s still possible that February will be our snowiest month across the Inland Northwest. The average snowfall for the season in Coeur d’Alene is 69.8 inches.

Further into March and April, conditions across the Inland Northwest should start to turn a bit drier. However, a lot does depend on the warming of the waters in the south-central Pacific Ocean. Many scientists and forecasts are still predicting a weak El Nino to be declared in February and persist through the spring season. However, new data is showing that the ocean waters are beginning to show signs of some cooling near the Equatorial regions. Stay tuned.

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Contact Randy Mann at randy@longrangeweather.com