Researchers Challenge the 30-Year Climate Paradigm

Deforestation did not reduce CO concentration₂ in the sky.

It is a challenge to see a world without trees today, however, in the past before forests and humans appeared, the land was inhabited by shallow, shrub-like vegetation.

For a long time, researchers around the world believe that the reduction of atmospheric CO₂ conditions and the cooling of the Earth’s climate is caused by trees.

Until today at least. Now researchers at the University of Copenhagen, using a new method, have learned that the small vascular plants that filled the Earth before they became trees 385 million years ago may have played a bigger role than as previously thought.

“The new method has helped us calculate CO₂ the state of the atmosphere in the past based on fossils. This helps us understand climate changes in CO₂ conditions increase. Among other things, the first results suggest that small changes in CO₂ the situation has a greater impact on climate than previously thought,” says Associate Professor Tais W. Dahl of the Globe Institute at the University of Copenhagen.

This study can help us understand the processes that control the climate on Earth and for example, the effect of trees on the climate today.

“We initially used this method in the pre-forest era – a period that researchers agree was characterized by high CO levels.₂ in the sky. We used to think that deforestation reduced the amount of atmospheric CO₂ in the world. But instead of 4,000 ppm, which is the amount that researchers thought was found on the planet at the time, we have shown that the number may be 600 ppm, which is not far from the level we are approaching today, ” says Tais W. Dahl and adds:

“The fact that CO₂ the situation has not changed enough to mean that the climate is more sensitive to changes in atmospheric CO₂ conditions than previously thought. Debating the Earth’s climate is a hotly debated topic because it is affected by various processes such as cloud formation, water vapor and ocean currents, which may increase temperature changes. .”

By studying living plants and fossils, researchers are now able to calculate the amount of CO₂ in the atmosphere at the time fossils lived. A new method makes it possible to calculate CO₂ past weather conditions more accurately.

We need to focus on the “foundation” issue.

Tais W. Dahl and his colleagues do not believe that trees are good for removing CO₂ from space as previously believed. Shallow-rooted vascular plants that were present before trees do this with great success.

“We believe the emergence of ancient vascular plants, not forests, caused the greatest CO reduction₂ conditions. This is because vascular plants have shallow roots that, unlike tree roots, cannot hold on to nutrients from the ground and therefore need to absorb more nutrients from the soil below. of the world in mineral weathering,” says Tais W. Dahl.

And climate plays an important role in understanding how we can reduce CO levels₂ in the sky.

“Plants remove CO₂ from space for two reasons. The first is probably the one we can think of, which is that the plant itself absorbs CO₂ then turn it into sugar. But plants also absorb nutrients from the soil or rocks they live in by dissolving rock particles through chemical weathering. For this process, plants need CO₂ to dissolve minerals. This is the main reason plants and trees reduce CO₂ for a long time,” explains Tais W. Dahl.

This is also why trees may not be as important as Tais W. Dahl and his early colleagues believed. Because trees don’t have the climate as well as small plants.

Plants need to absorb more mineral nutrients from the soil than trees, and this results in more weather. Trees are immobile and have well-functioning roots, which help them retain nutrients and create a more closed system. Therefore, over time, older plants weather more than trees, and it is mainly through climate that trees and plants help remove CO.₂ from space,” explains Tais W. Dahl.

Step to find other solutions

Does that mean we need to start planting more vascular plants – instead of trees and forests – to curb the amount of CO₂ in the sky? Not so, says Tais W. Dahl.

“Trees are good for other reasons; Biodiversity is another. And now we need to remember that the solution to today’s climate change is not just more climate. More is needed to combat climate change.”

This study adds to our knowledge of what controls atmospheric CO₂ conditions and how sensitive the climate is to changes in greenhouse gases in the atmosphere. And then it can help give us an idea of ​​how natural processes affect CO₂ conditions.

“Finding solutions is important. But to find solutions, we need to know as much as possible about the processes that can remove CO₂ from the atmosphere, for example, planting trees and more climate,” says Tais W. Dahl and adds:

“To understand how this works around the world, and what the consequences are, it’s a good idea to look at what happened in the past when the Earth saw big changes and these patterns changed. And that’s what this study does. ”

Reference: “Atmospheric low CO2 levels before forest ecosystem rise” by Tais W. Dahl, Magnus AR Harding, Julia Brugger, Georg Feulner, Kion Norrman, Barry H. Lomax and Christopher K. Junium, 20 December 2022,