Earth’s axis of rotation is tilted almost 80 centimeters to the east between 1993 and 2010. This is the point around which the planet revolves. Imagine top. Now imagine that he suddenly leans in the other direction. This atypical movement was already discovered by scientists a few years ago, but now they have more information about what causes it. And yes, we have a lot to do with it.
The first thing the researchers found was the impact of climate change. In a study published in 2013, they confirmed how the melting of polar ice and glaciers changed the distribution of the mass of water on the planet so much that it affected its rotation. But some of the same researchers have just identified a new factor: mass extraction of groundwater.
The earth’s axis tends to move naturally in a process called polar motion. But again, visualize the top. Now imagine that you are adding weight to it on one side. Similarly, the Earth will rotate a little differently when water moves around the planet.
A study published in Geophysical Research Letters (Journal of the American Geophysical Union) claims that groundwater extraction is the second cause that has the greatest impact on the earth’s axis. Only behind the melting layers of Greenland, Antarctica and mountain glaciers.
This displacement of water also affects sea levels. “Pumped groundwater evaporates into the atmosphere or flows into rivers. It will enter the oceans through precipitation or discharges,” Kee-Weon Seo, professor of earth sciences at Seoul National University and lead author of the study, told The Associated Press. BBC.
Effect of water extraction on the earth’s axis
According to other scientific studies, groundwater depletion worldwide doubled between 1960 and 2000. It is estimated that about 284 billion liters per year are mined each year. All this is due to the increase in the world’s population, the expansion of irrigated agricultural areas and the development of other types of economic activity.
Another investigation warns that 47% of river basins are being depleted at an accelerated rate. That is, they are used up faster than they can be replaced. Increased droughts due to climate change could also lead to increased groundwater extraction. In fact, more than half of the world’s major lakes dry up.
“I’m not surprised it affects” the Earth’s axis of rotation, said Matthew Rodell, a geologist at NASA’s Goddard Space Flight Center. The newspaper “New York Times. However, “it’s impressive that they were able to crack it on the data,” he added.
The change in the earth’s axis is not big enough to change the climate. However, the researchers emphasize that this measurement can also serve as a way to monitor groundwater abstraction. For example, they created a model that allowed them to determine that most of the planet’s water was redistributed to mid-latitude western North America and northwestern India.
Ki-Won Seo, head of the study, said BBC he was very pleased to discover the hitherto inexplicable reason for the change in the axis of rotation. “On the other side, As an Earth dweller and parent, I am concerned and surprised that groundwater pumping is another source of sea level rise.”
Seo draws attention to what can happen to coastal populations over time due to rising sea levels. “My generation will be fine, but my kids might be in trouble.”
Source: Hiper Textual
