We all know that the Earth spins on its axis. But a more accurate way to describe it is that our planet spins like a top.
When you watch a spinning top, you will notice that it wobbles slightly. As the spin slows down it wobbles even more. Also, if you do something to disturb the top or change its weight on one side, then it really goes off-kilter.
Well, the spinning earth acts in just the same way. For example, the tip of the north pole today points toward the star Polaris. That’s why it’s called the Pole Star. But 5,000 years ago, the Earth’s axis was pointed at the star Thuban. Go back 10,000 years and the “Pole Star” was Vega in the constellation Lyra.
That’s because the earth is wobbling slightly. Where the axis point drifts across the heavens slowly as the centuries pass by.
The rate of the shift in the polar axis is generally known. It is also understood that the rate of polar drift can vary. However, scientists have been noticing that the rate of polar drift has increased dramatically in recent years. Measurements taken by the American Geophysical Union show that, between 1995 and 2020, the speed of the pole movement sped up about 17 times when compared to the average speed that was recorded between 1981 and 1995.
Scientists believe that climate change is the reason.
Here’s why:
Go back to our analogy of a spinning top. When you change the weight distribution of the top, it changes the way it wobbles. Climate change is causing massive shifts of weight on the surface of the earth. That’s happening because glaciers are melting on landforms, shifting the weight of the ice from land to water. The oceans are now “sloshing around” in a way that was different from before, producing more wobble.
Another way human behavior is changing the Earth’s balance is by drawing up trillions of gallons of groundwater from deep beneath the Earth’s surface. This is water used by massive urban centers that get bigger every year. It is also used for agricultural irrigation to grow more food to feed the more than seven billion people on the planet.
This change in the angle of the Earth’s axis has profound implications on weather patterns because it changes the angles at which the sun’s rays strike different parts of the globe – but that’s a topic for another article.