CO2: An amazing gas
With carbon dioxide (CO2) and water as building blocks and the sun for energy, photosynthesis has made possible our existence and that of nearly all the other plants and animals on earth. When wood and fossil fuels burn, CO2 is released together with energy the sun had stored in them, energy that heats buildings, generates electricity, and powers the world’s engines. Similarly, when we metabolize the carbon-laden food we eat using the oxygen we breathe, we exhale CO2 and spend the energy released to warm our bodies, run our brains, and drive our muscles.
Myriad sea creatures use CO2 to build their shells, and the gas does its own construction work. With the help of water, it carves limestone caves, creating the stalactites and stalagmites that make them spectacular. The holes in bread and cake are made by CO2. And of course it brings a tang to many drinks. The gas is valuable for fighting fires, and in solid form it is the refrigerant Dry Ice.
In 1896, the Swedish chemist Svante Arrhenius predicted that the earth would eventually be warmed by CO2 formed as a result of the Industrial Revolution. In 2026, huge numbers of people, including the currently most powerful man in the world, do not believe this yet despite overwhelming evidence that it is happening. By any measure, that is a slow learning curve. Now an existential threat, CO2 is responsible in large part for the extreme storms, floods, droughts, mega wildfires, glacier melting, sea level rise, massive extinction of species, and the beginning of mass migrations of people that we are experiencing. We possess the knowledge and tools needed to solve the climate change problem, but will we wake up in time to spare our grandchildren and theirs from life on a hellish planet?