Modified June 25, 2023 | 11:48
If you’ve ever played with a spinning top, you’ve probably noticed that the slightest touch can tilt its axis, changing the course of its rotation. Interestingly, our blue planet behaves similarly, only on a much larger scale.
From 1993 to 2010, the earth tilted eastward nearly 80 centimeters due to the abstraction of groundwater for human consumption, agriculture, and industry. This is one of the impressive impacts of the Anthropocene, an era marked by human activities affecting the geological changes of the planet.
The scientific investigations reported in the Geophysical Research Letters reveal a remarkable change. Over the course of 17 years, humans have extracted an estimated 2,150 gigatons of water from the ground, raising sea levels by more than 6 millimeters and shifting the Earth’s axis of rotation by redistributing the planet’s mass.
This surprising discovery makes it clear that the distribution of Earth’s mass even if water makes up only 0.05% of it can profoundly affect the balance of our planet.
The influence of groundwater abstraction on the Earth’s rotation
It is important to note that this change in the Earth’s axis of rotation is not solely due to the melting of glacial ice, a phenomenon traditionally thought to be the primary cause of the redistribution of Earth’s mass. KiWeon Seo, head of the Seoul National University study, emphasizes that groundwater redistribution has the greatest climatic influence on the axial deviation.
In their groundbreaking study, the researchers took this new perspective into account. They created models that accounted for the impact of melting ice caps and glaciers, as well as various groundwater redistribution scenarios.
The results were impressive. The model was in close agreement with the actually observed changes in the tilt of the Earth’s axis of rotation and the shift in the true north pole. The biggest surprise was that the redistribution of water from the midlatitudes, mainly to western North America and northwestern India, had an even larger impact than the melting of glacial ice.
Drain the groundwater, turn the earth
As with a spinning top, the rotation of the earth is affected by the displacement of the mass. When water is extracted from the subsurface for various human uses, it eventually flows into the sea and causes mass changes that shake the Earth’s rotation. However, this shift is happening slowly and is influenced by changes in the atmosphere, oceans and solid parts of the earth.
Despite this fascinating discovery, we can breathe a sigh of relief. According to scientist Surendra Adhikari, groundwater extraction is unlikely to disrupt the seasons. But that doesn’t mean we can ignore it. From a geological perspective, a shift of 80 cm could affect our climate and illustrate how seemingly insignificant human activities can have farreaching consequences on a global scale.
So the next time you sip a glass of water, think about the journey that water has taken from the depths of the earth, through human hands, into the oceans, and finally on a slight incline of our planet that rotates like a spinning top turns . It is a reminder of how closely our life is connected to nature.
EditorinChief of Mistérios do Mundo since 2011. I love to travel, enjoy good music and read. It won the Digital Influencer Award in the Oddities category.