Earth’s rotation slows down in a staircase pattern

MADRID (EUROPA PRESS) -The Earth’s rotation has been slowing over time due to tidal dissipation, but the rate of this slowdown has not been consistently established.

This is the conclusion of a landmark research article published in the journal Proceedings of the National Academy of Sciences (PNAS).

Chinese researchers, in collaboration with their counterparts from France, Germany and Ireland, analyzed eight sets of geological data to reconstruct the Earth’s rotation history from 650 million to 240 million years ago.

Their findings allowed them to test physical models of tides and identify a staircase pattern in the Earth’s slowing between 650 million and 280 million years ago, Xinhua reported, citing Science and Technology Daily.

Specifically, there are two periods of large deceleration of the Earth’s rotation (650 to 500 million years ago and 350 to 280 million years ago), separated by an interval of stagnant deceleration from 500 to 350 million years ago.

These two periods roughly coincided with the Cambrian explosion and the largest mass extinction event in Earth’s history, the paper notes, adding that the two periods may have provided the conditions necessary for the evolution of the first marine ecosystems.

The models indicated that, except in very recent times, tidal dissipation is the main driver of the slowing of Earth’s rotation, according to the research paper.

The study has important theoretical significance for exploring the climate, environment and biological evolution of the slowing Earth’s rotation, said Ma Chao, a professor at Chengdu University of Technology.

The research team will further study the internal links between Earth’s rotation changes and natural phenomena such as the Earth’s magnetic field, tidal actions and climate change to build a more complete and accurate Earth system evolution model, Ma said.