Carbon dioxide is often described as the main driver of global warming. However, its role on Earth is far more complex. In his book The Story of CO₂ Is the Story of Everything, science journalist Peter Brannen explains that carbon dioxide is not only a climate risk. It is also the foundation of life on the planet.
Life on Earth depends on carbon. That carbon comes primarily from CO₂. Plants absorb carbon dioxide through photosynthesis. Animals then rely on plants, directly or indirectly, for survival. As a result, the entire biosphere rests on a carbon-based system.
Over millions of years, carbon became buried in dead plants, algae, rocks, and ocean sediments. Meanwhile, oxygen slowly accumulated in the atmosphere. This process made complex life possible. At the same time, atmospheric CO₂ levels continued to regulate global temperatures.
The link between carbon dioxide and climate is direct. If CO₂ disappeared from the atmosphere, Earth would rapidly cool and enter a deep freeze. In contrast, releasing all buried carbon by burning fossil fuels would dramatically heat the planet. Ice would vanish. Tropical conditions would extend to the poles.
Today, scientists warn that the pace of change is unprecedented. According to Brannen, humans are emitting carbon dioxide around ten times faster than during the period leading up to the Permian mass extinction, the largest extinction event in Earth’s history. That event was associated with massive CO₂ releases and extreme warming.
Importantly, Brannen notes that this does not guarantee a similar extinction. Nevertheless, it places humanity in unknown territory. Geological records show that rapid carbon release has always reshaped life and climate.
For the clean energy transition, the message is clear. CO₂ itself is not the enemy. Unchecked emissions are. Managing carbon through clean energy, efficiency, and carbon removal will decide whether CO₂ remains a life-supporting molecule—or becomes a destabilizing force.
