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Drifting of the magnetic North Pole - Frank Donovan W3LPL

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    Drifting of the magnetic North Pole - Frank Donovan W3LPL

    Confusion among hams about the increasingly rapid drift of the magnetic north pole By W3LPL, Frank Donovan

    There's considerable confusion and misinformation in the amateur radio community caused by misinterpretation of press reports about the surprisingly rapid rate of northward drift of the Earth's magnetic north pole over roughly the last 35 years.

    Contributing to the confusion are two broadly defined magnetic north
    - the fairly rapidly drifting dip north pole (often called the magnetic pole), and
    - the relatively slowly drifting geomagnetic north pole

    The dip north pole being discussed in current news reporting is drifting northward ten times more rapidly than the more lethargic geomagnetic north pole which has much greater significance to DXers and contesters.

    The slowly drifting geomagnetic north pole has much greater significance to DXers and contesters because the northern auroral oval
    - which greatly affects HF propagation over the north Atlantic and north Pacific Oceans -- is closely centered on the geomagnetic north pole and not on the dip north pole. The geomagnetic north pole has been drifting generally northward only about three miles per year.

    The geomagnetic north pole's location is defined by global models of the Earth's magnetic field, its location cannot be determined by direct measurement. Its currently located on Ellesmere Island about
    165 miles southwest of Alert, Nunavut the northernmost permanently inhabited place on Earth. Its drifting much more slowly than the dip north pole, it has drifted roughly northward only about 75 miles over the last twenty years.

    The much more rapidly drifting dip north pole is defined to be the location in the northern hemisphere where the geomagnetic field is exactly vertical as determined experimentally by magnetic surveys on land, ships and spacecraft. Its location is currently near the center of the Arctic Ocean about 250 miles southeast of the geographic north pole roughly halfway between Nunavut and Eastern Siberia. The location of the dip north pole is important to navigation but of relatively little importance to space-based phenomenon such as HF ionospheric propagation.
    73 Al 4L5A