ÌÇÐÄÊÓƵ

A research team led by Academician Jin Zhijun from the Institute of Energy, Peking University, has revealed how interactions between Earth's tectonic activity and astronomical cycles jointly shaped the planet's climate and carbon cycle during the Late Paleozoic Era (360–250 million years ago, or 360–250 Ma). The findings are in Nature Communications, titled "Tectonic-astronomical interactions in shaping Late Paleozoic climate and organic carbon burial," offering new insights into the deep-time climate system.

Between 360 and 250 Ma, Earth underwent dramatic transformations. Continents merged to form the supercontinent, glaciers spread across vast regions, and thick layers of coal and organic-rich rocks began to create the materials that would later become today's fossil fuels. Scientists had long known that both tectonic activity (such as volcanic eruptions and mountain building) and astronomical cycles (changes in Earth's orbit and tilt) influenced these events, but how the two worked together remained unclear.

This study explains how processes inside Earth and forces from space interact to control the planet's climate. It shows that when tectonic activity was strong, the climate became unstable, while during quieter tectonic periods, the climate stabilized, creating ideal conditions for large-scale organic carbon burial. Understanding these natural interactions helps scientists better predict how Earth's climate may respond to future changes in COâ‚‚ and other factors.

The team divided the Late Paleozoic Era into three major tectonic phases using plate reconstructions, geochemical data, and carbon cycle modeling. They identified periods of enhanced activity (~360–330 Ma and ~280–250 Ma) marked by rapid ridge and subduction expansion, volcanism, and climate instability, and a middle phase (~330–280 Ma) of relative tectonic calm with reduced CO₂ release, cooler temperatures, and stable climates.

Astronomical signals in sediments were most visible during the quiet phase when orbital cycles strongly influenced temperature and rainfall, but became obscured during active phases due to volcanic COâ‚‚ spikes. Simulations confirmed that COâ‚‚ levels acted as a major amplifier of climate swings, linking tectonic forces to global climate balance.

This work changes how scientists understand ancient climate history and shows how Earth's interior and outer-space cycles have always worked. This study provides a new perspective on the long-term carbon cycle regulation mechanism and also provides an important historical reference for modern climate research.