Earth's velocity swings

One of the most characteristic signs of cosmic phenomena is correct repeatability, cyclicity. For example, the rotation of the Earth around its axis and the Sun. But, for astronomers for a long time is not a secret, that the duration of the earthly day is gradually increasing. Then, why are there such Earth's velocity swings? For example, it is estimated that in remote times the day was much shorter than today and that in a few tens of millions of years they will become noticeably longer than our usual day.

Then, why are there such Earth's velocity swings?

The main cause of this phenomenon is known - the lunar tides, which, from day to day, slow down the Earth. However, with the advent of accurate methods of measuring time, it is noted that sometimes there are fluctuations in the Earth's rotation speed, about 100-200 times more significant than those that should occur due to tides. What are the forces that make the giant body of our planet rotate faster, then more slowly?

Some scientists come to the conclusion that the observed oscillations of the Earth's velocity are associated with fluctuations in solar activity. The fluxes of charged particles that are ejected by the Sun affect the speed of the Earth's rotation through its magnetic field.

Calculations show that the energy of the Earth's velocity oscillations is about 1021 J per day. On the other hand, solar corpuscular streams bring to the Earth a magnetic energy of the order of 1028 J. It turned out that the influence of the magnetic field of corpuscular streams for a full explanation of the Earth's velocity oscillations is not enough. Then, what is the mechanism for the partial transfer of this energy to the magnetosphere of the Earth?

Scientists have suggested that particles are ejected from the surface of the Sun not only in the form of streams, but also in the form of separate giant clouds of plasma - "plasmoids".

A similar plasmoid, moving in outer space and many times larger than our planet, has its own powerful magnetic field. At a meeting with it, it exerts such a strong influence on the earth's magnetic field that as a result magnetic storms and oscillations of the Earth's velocity arise as it rotates.

On the other hand, it is possible that a certain proportion of these oscillations are caused by the movement of air masses in the earth's atmosphere, the so-called atmospheric circulation. When the air masses move between them and the surface of the planet, frictional forces arise. Through these forces, atmospheric circulation can have a retarding or, on the contrary, accelerating effect on the rotation of the Earth.

To verify the last assumption, we can analyze the average monthly atmospheric pressure maps for the entire Earth for several consecutive years and with their help to calculate how our planet should rotate in a certain period under the influence of frictional forces between the air masses and the earth's surface.

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