A new study has revealed that changes in Earth’s plant life significantly accelerated climate shifts during the late Miocene epoch.
The research, recently published in Science Advances, was led by scientists from the Institute of Atmospheric Physics (IAP) of the Chinese Academy of Sciences.
The late Miocene, which occurred between 11.6 and 5.3 million years ago, was a pivotal period when the planet transitioned from the warmth of the middle Miocene to cooler conditions similar to those of today. While previous studies highlighted declining carbon dioxide levels and tectonic activity as major factors, these did not fully explain the global climate changes observed.
The new study emphasizes the crucial role of vegetation feedbacks—how changes in plant cover can influence climate—in intensifying cooling in the high northern latitudes and altering rainfall patterns in lower latitudes.
In regions closer to the poles, dense forests gave way to expansive grasslands as temperatures dropped. This shift in vegetation increased the Earth’s surface reflectivity and affected levels of water vapor, clouds, and sea ice, leading to further cooling. In some areas, these effects were even more pronounced than those caused by decreasing carbon dioxide levels.
By combining geological evidence with climate models, the researchers were able to distinguish the individual impacts of carbon dioxide reduction, tectonic movements, and vegetation changes on the late Miocene climate.
“This study helps us better understand the mechanisms behind the late Miocene climate shift,” said Professor Zhang Ran from the IAP. “It emphasizes how vegetation feedbacks can influence the global climate—both in the past and in the future.”
Unlike today’s rapid, carbon dioxide-driven warming, the late Miocene was marked by cooling trends. The findings underscore the often-overlooked impact of plant life on climate systems, offering valuable insights for future climate change research.
