Chinese hydroelectric dams slow down the Earth

The displacement of the mass of giant water in the largest Tam Hiep hydroelectric dam on the planet makes the Earth rotate slower due to inertial torque.

on the Changjiang River in Hubei Province, China, providing clean energy to the pressing needs of the people of this country, but also causing many environmental impacts. The mass of giant water stored at the Three Gorges Dam is enough to alter the Earth's rotation, according to Futurism.


Overview of the Three Gorges Dam.(Video: Xinhua).

The last 32 transmitters of Tam Hiep dam went into operation at the end of July 2012. The dam's water is capable of producing about 22.5 million kilowatt hours of electricity (or 22,500 megawatts), equivalent to 15 nuclear reactors.

However, since the announcement of this $ 30 billion project, China has suffered a heavy reaction from scientists and environmental activists. Many experts believe that dams will cause incalculable consequences, including pollution, earthquakes, landslides, disturbing people's lives when more than 1.3 million people are forced to relocate, destroying historic and habitat of endangered animals.

Three Gorges is about the total capacity after the project is completed. When the water level is at the highest level, the total area of ​​land submerged is 632 km 2 . The reservoir has a capacity of about 39.3 km 3 and the volume of water will be up to 42 billion tons.

The displacement of such a large mass of water will affect the rotation of the Earth due to the phenomenon of inertial torque, in which the inertia of a rotating solid object corresponds to the rotation its.

Picture 1 of Chinese hydroelectric dams slow down the Earth
Three Gorges Dam seen from above.(Photo: YouTube).

The larger the distance from the object to its axis, the slower the object rotates. For example, an ice skater must squeeze his arm into his body to reduce inertia if he wants to spin faster. Similarly, a faster scuba diver will choose to embrace the pillow.

Pushing 42 billion tons of water to 175 meters above sea level will increase the Earth's inertial torque, thereby slowing the rotation of the planet, though the impact will be extremely small.

According to scientists from the US Aeronautics Agency (NASA), the movement of such a large mass of water will add 0.06 milliseconds, making the Earth slightly rounded in the middle and flatter at top. The impact also caused the pole to deviate by about two centimeters.

The researchers believe that this effect is not worrisome because the Earth's rotation changes frequently due to the influence of the Moon and earthquake. The Moon draws farther away from the Earth, causing the planet's rotation to change slightly. The 2011 super earthquake in Japan has caused the days on Earth to be 2.68 seconds longer.