We can’t imagine all the treasures that can be found in the ground. The earth, the leaves, the riverbeds… all these natural elements speak to those who know how to listen to them. They tell the story of our planet and the climatic eras it has gone through. They act as substitutes for direct observations of past climate. It is thanks to them that scientists can make assumptions about what the Earth has been through, but also about what awaits it.
In a study published in December 2025 in the journal Nature Geoscience, researchers from the University of Utah and the Colorado School of Mines explain that they succeeded in modeling the frequencies and strength of precipitation according to periods of global warming during the Paleogene, between 66 and 48 million years ago.
The results of this study go against commonly accepted ideas about climate
It is generally accepted that humid regions become more humid as the Earth warms and that drier ones become even drier. “There are good physical reasons for this reasoning. But our study was a bit surprising since even moderate latitudes tend to show drying, underlines Thomas Reichler, professor of atmospheric sciences and lead author of the study at EurekAlert. This is due to the variability and distribution of precipitation over time.”
Clearly, rather than analyzing the volume of annual precipitation on the globe during the Paleogene, the research team studied plants, soils and river beds to understand how often and under what conditions rain fell at the time. They concluded that the polar regions were very humid at this time while the moderate latitudes were drying out.
A window open to the future of our planet?
The study of the Paleogene is all the more interesting because it is the period when the planet was hottest, probably 18°C above the pre-industrial temperature. Some scientists believe that the state of our planet at this time is similar to what Earth will look like in the future if the worst-case scenario comes true.
Although it represents the best way to understand past climate, the use of proxies to analyze Paleogene precipitation is not an infallible method. However, it can allow climate specialists to strengthen their models of the climate and the future of the planet. And thus, perhaps, push public authorities and economic actors to take actions to reverse or mitigate the effects of current climate change.
