We have also changed the rotation axis

A few years ago, Jet Propulsion Lab scientists They estimated That the filling of the three throats, the huge hydroelectric project of China, implied the movement of a mass of water so vast that it was capable of lengthening 0.06 microseconds The land day. The Chinese dam is a singular case for its magnitude, but it is only one of the tens of thousands of reservoirs that populate our planet.

The global impact of these reservoirs has now undergone.

Displacing the poles. A new study He has found evidence of the geological impacts that the construction of dams can have on a global scale. They observed that the construction of dams had caused a slight displacement of the geographical poles of the planet,

Geographical poles? As little ones, they will probably teach us that the geographical poles and magnetic poles of our planet were located at different points of their respective polar circles. They would surely teach us that the magnetic poles tend to move slowly over time while the geographical poles remain static forming the Earth’s rotation axis.

This is more or less true, but not at all: geographical poles can also move. The reason is in the structure of the earth. Our planet is not a block of uniform rock but is formed by several concentric layers.

While the outer layer is essentially solid, the interiors are not. As if it were a mat on a pool, the “float” earth’s cortex on the mantle, which implies that it can move more or less independent displaced by the physical forces that are applied in each case.

Redistributing the dough. Forces that in turn depend in part of the distribution of the masses that we find in this superficial part of the planet, a distribution that is altered every time we introduce changes in the geography of our planet. These changes include the displacement of large masses of water to the swamps, water that in “normal” conditions would have returned to the ocean dragged by the rivers in which we build prey.

“As we catch water behind the dams, we not only eliminate the water from the oceans, reducing sea level, the mass is also distributed in a different way around the world,” explained in a press release Natasha Valencic, co -author of the study.

6,862 reservoirs. The study responsible for the study analyzed the impact of water accumulation in 6,862 reservoirs, an accumulation of water that twice represents the volume of the Grand Canyon of Colorado. The team observed that between 1835 and 2011 this accumulation of water could be responsible for almost a meter of displacement in the axis of terrestrial rotation with respect to the planet’s surface.

The displacement would be divided into two stages, the first between 1835 and 1954, in which the pole would have displaced 20.5 cm to the 103 meridian as a result of the construction of dams in Europe and North America. The second, between 1954 and 2011, would have been dominated by the construction in Asia and Africa del Este, carrying the 57 centimeters pole towards the 117 western meridian.

The details of the study were published In an article In the magazine Geophysical Research Letters.

More than reservoirs. The implications of these geographical changes are not extreme: after all the tectonic plates do not stop moving at our feet despite the fact that their rhythms usually be more slow. However, knowing these little movements can help us understand some of the geological dynamics and the impact of the human being on them.

“We are not going to fall into a new ice age because the pole has modified around a meter in total, but it has implications for sea level,” Clarified Valancic.

In Xataka | China is raising an unprecedented dam where millions of people live. The problem is seismic activity

Image | Ali Madad Sakhirani