April 29, 2021

The media are writing: "The climate change has shifted the earth's axis". Is this true? The scientist from St. Petersburg State University gives explanations

Humanity's impacts on our planet's climate are so profound that they have caused shifting of the axis upon which Earth spins around. This statement was made by scientists from the Institute of Geographic Sciences and Natural Resources Research in China. But not everyone agrees with him.

The study results were published in Geophysical Research Letters, and Science Alert give a brief description.

The researchers studied the phenomenon of true polar wander, in which the geographic locations of Earth's north and south poles drift with respect to the planet's rotational axis. The extent of wander is not constant, as evidenced by a pronounced directional change from westwards to eastwards that was first seen in the 1990s.

n the new study, Shanshan Deng and fellow researchers examined the extent to which changes in terrestrial water storage in recent decades contributed to the amount of true polar wander recorded in the same timeframe. The Water storage affect the distribution of mass on Earth, and when you're dealing with a spinning object – whether a spinning top, or an entire planet – the way its mass is distributed affects the way it spins.

"The faster ice melting under global warming was the most likely cause of the directional change of the polar drift in the 1990s," - Deng explained. - The other possible cause is the change in the terrestrial water storage distribution in non‐glacial regions due to climate change and irrigation and other anthropogenic activities."

The "Nauka" (Science) channel asked Pavel Svyashennikov, PhD, Associate Professor of the Department of Climatology and Environmental Monitoring of St. Petersburg State University for comment.

"I read this article and, honestly, I was surprised that it was published in this magazine. I am in a different opinion. The Chinese scientists were too categorical in what they said," - said Svyashennikov. - It is without doubt that all processes are interconnected. However, the observed climate changes could not have caused such changes in the position of the Earth's magnetic axis. The changes that have occurred were too small: in reality the glaciers have not melted in so great extents, this process takes quite long periods.

The scholars refer to the changes in the mass of glaciers on land and the increase in the amount of fresh melted water. But by mass, this is a sufficiently small amount in comparison with the mass of the Earth. If we were able to control the position of the Earth and its magnetic field with such small amounts, then one can't imagine what would happen here on Earth! ..

This is more like a journalistic scoop, and not a scientific message. Maybe the researchers themselves meant something else. The conclusions in the article were made prematurely and incorrectly.

I hope they worked out everything correctly with the position and change of the pole, but they only proposed a hypothesis, which they do not confirm with anything: "We have two processes running: glaciers are melting and the magnetic pole is drifting. So, let's assume that these phenomena are interrelated." However, the article does not present any mechanism of this interrelation.

I am in the opinion that the main reason for the change in the position of the magnetic poles is something different. The poles drift all the time. If we look at the position of the magnetic pole over several thousand years, we see that it has moved for quite a long way. For the geophysicists the shift of the North Pole is quite noticeable, but for ordinary people it is quite a small shift. So I am sceptical about the stated cause, although agree with the existence of the phenomenon.

We should note that the article does not discuss the axis of the Earth, around which it spins, although it is also undergoing changes. We are talking about the drift of the magnetic axis. We deal with the position of the North and South Poles, and they periodically shift over long distances. There is even such a hypothesis that after a certain period of time they will switch places altogether. The North Pole will take the position of the South Pole. The only thing this will lead to is that the compass will work differently.

Of course, from the point of view of climate and the existence of life, the Earth's magnetic field plays a great role and affects what happens in our world. The existence of a magnetic field around the Earth largely contributes to maintaining the atmosphere around our planet. If there were no magnetic field, the flow of various particles - the radiation emitted from the Sun, which is called the solar wind - would remove the atmosphere from the Earth.

I think that the recently discovered change will not have any consequences. We don't notice it at all. In the future, everything will depend on the extent of general change of the Earth's magnetic field. Of course, if it weakens, it will have an impact: those particles, flying to the Earth, including from the Sun, will start penetrating much deeper to the surface of the Earth. While the change in the position of the magnetic field will lead to the case that the aurora borealis will occur in different areas".

Sources:

https://agupubs.onlinelibrary.wiley.com/doi/10.1029/2020GL092114

https://www.sciencealert.com/earth-s-axis-has-already-been-shifted-by-climate-change-scientists-say