Scientists have discovered that humans have physically altered the rotation of the planet by building thousands of large dams. For the first time, researchers from Harvard calculated the exact influence of these structures on the movement of the earth’s poles and obtained such an amazing result. Humanity on Earth has become a geological force.
Humans have changed the rotation of our planet. Photo: Unsplash
Over the past two centuries, humanity has shifted the geographical poles of the Earth by 113 cm. The figure seems minuscule on a planetary scale, but the fact remains that our civilization has literally rocked the planet. “Imagine a rotating balloon that a fly has landed on,” explains Natasha Valensik, lead author of the study.
The same thing happens with the Earth. When we block rivers and collect water in huge reservoirs, the mass of the planet is redistributed. Billions of tons of water are concentrated in new places, and the planet reacts by shifting its axis of rotation.
The researchers analyzed almost 7,000 dams built from 1835 to 2011. Only giant structures were taken into account — each contains at least a cubic kilometer of water. Together, these reservoirs hold twice as much water as the Grand Canyon.
Interestingly, the poles moved in different directions depending on where the dams were built. From 1835 to 1954, the main construction took place in North America. This pushed the North Pole in the opposite direction — to the east, to the 103rd meridian, which runs through Eurasia. Since the 1950s, the boom in dam construction has moved to East Africa and Asia.
The pole reacted by turning towards the 117th meridian west, crossing North America. The most powerful dam on the planet, China’s Three Gorges, single-handedly slows the Earth’s rotation by 0.06 microseconds and shifts the pole by 2 cm when the reservoir is fully filled. This is the result of the work of a single structure.
The pole shift directly affects GPS navigation and astronomical observations. Satellite communication systems must constantly adjust calculations based on changes in the position of the Earth’s axis. But there are also climatic consequences.
When the axis shifts to one side, the sea level drops in the hemisphere where the pole is moving. At the same time, water rises in the opposite hemisphere. If the pole goes to the northeast, then there will also be a decline in the southwest, and an upswing in the remaining two quarters of the planet.
The influence of dams on the Earth’s rotation is less than other factors by about an order of magnitude. Melting glaciers has a much more powerful effect. Recent studies have shown that changes in the ice cover and groundwater slow down the rotation of the planet by 1.33 milliseconds per century. This process may in the future become a stronger brake on the rotation of the Earth than the influence of the Moon through the tides.
Ву Daria Artsybasheva
