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Earth's Misunderstood Molecule

November 2, 2026 · 59 min

Show notes

Carbon dioxide is more than an industrial pollutant driving climate change. The gas also played a pivotal part in the dramatic story of the beginning of all life. Starting in the ocean depths, dissolved CO2 commingled in a turbulent mix of chemicals heated by hydrothermal vents may have kickstarted carbon-based life. As the planet’s thermostat, carbon dioxide has taken the Earth on wild temperature swings, from sweltering toxic hothouses that drove mass extinctions to the frigid Snowball Earth from which early life barely escaped. With life’s growing complexity, CO2’s role evolved. Exhaled by animals and enlisted by plants in photosynthesis, the gas eventually earned its discordant reputation when belched by industrial chimneys. Now, burning fossil fuels have us playing with fire as we test the limit of our stable climate upon which human civilization has flourished. 

Guest: 

Peter Brannen – science journalist and author of  “The Story of CO2 is the Story of Everything; How Carbon Dioxide Made Our World.”  

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