Science journalist Peter Brannen, in his latest book "The story of CO2 is the story of everything" claims that Carbon dioxide (CO2) is the most important and yet most misunderstood molecule on Earth.While mainstream narratives portray CO2 as the “evil supervillain” associated with the modern climate crisis and gigatons of pollutants released, Brannen offers a much broader and deeper view.

According to Brannen, who was inspired by conversations with leading planetary scientists, CO2 is not just an industrial pollutant, but a key player in the four-billion-year-old drama of life on Earth. It is the molecule that shaped our planet, regulated the global carbon cycle, shaped geology, and drove evolution. Brannen emphasizes that from the earliest beginnings of life to the development of human civilization and our global economic system, the ebb and flow of atmospheric CO2 has played a role in virtually everything under the sun. Understanding CO2, he says, means understanding the very fabric of our world.

CO2 and past mass extinctions Brannen's reassessment of CO2 also builds on his previous work on the book "The End of the World," in which he documented five of Earth's biggest mass extinctions. He found that while a space rock triggered the most recent extinction, which wiped out the dinosaurs 66 million years ago, The other four major mass extinctions and dozens of smaller events in the fossil record are linked to major biogeochemical events, which usually involve huge increases in atmospheric CO2.These CO2 spikes were followed by extreme global warming, ocean acidification, and other unpleasant effects of climate change. This suggests that the planet’s current fossil fuel burning experiment has much in common with these horrific, planetary-scale events that were literally the worst things in Earth’s history.

CO2 is the miracle that sustains life Yet CO2 is not just bad. It is fundamentally different from other industrial byproducts. Life on Earth – the biosphere – is based on carbon, and the source of this carbon is CO2.. In “normal” times, when CO2 circulates through the biosphere, air, rocks, and oceans in the global carbon cycle, it is a key component that makes Earth a special and habitable place. Without CO2, Earth would quickly freeze over and most of the biosphere would perish in a “snowball Earth” episode, while on Venus, its excessive accumulation causes a hellish greenhouse effect. So it is good—indeed, necessary—to have CO2 in Earth’s air, but its amount must be balanced, because we can have too much or too little.

Humanity as "fire elves" and a planetary battery Brannen sees all of human history through the lens of the global carbon cycle. He explains how humans became a “geomorphological force.” He describes the interaction between carbon in the ground (fossil fuels) and oxygen in the air as "creating a large planetary battery."This battery was created by an imbalance between the reactive, oxidizing atmosphere and the reduced organic matter underground. In recent centuries, humanity has learned how to combine them again to obtain energy. Brannen compares human industrial civilization to "fire elves" who move all the carbon from the interior of the crust into the atmosphere, almost instantly discharging this huge planetary battery that took the entire history of the Earth to build.

An uncontrolled experiment and the future Although CO2 levels were higher in Earth's past (for example, 50 million years ago in the Eocene), Brannen warns that thinking this is relevant to our current situation is a misunderstanding of "deep time." Our biosphere is adapted to a "glacial" world with polar ice caps that persisted for millions of years. Our current problem is not just the volume of CO2 released, but above all its speed.We are currently emitting CO2 at a rate 10 times higher than it was during the eruptions that led to the Permian mass extinction – the largest known extinction in Earth’s history. This puts us in “uncharted territory.”

Brannen expresses some optimism about advances in solar energy that could disrupt the fossil fuel world. But he stresses that Joint political action will be needed to stop burning fossil fuels. Despite global challenges like the energy demands of artificial intelligence and political obstacles, Brannen believes that understanding the scale of the problem is key. Thinking about “deep time” can be humbling and even comforting, reminding us that we are not the center of a show and that the future will likely look very different. But personal relationships and love remain the most important things. Co2AI