dioxide

And at long last carbon dioxide shows up — probably with a lavish musical number, like Thomas Jefferson in Hamilton.

But both parts — getting oxygen in and getting carbon dioxide out — are equally important.

These act as a blanket, trapping the sun's heat, with carbon dioxide doing most of the damage.

And electrofuels can be made by mixing hydrogen with carbon dioxide captured from industrial plants, in a process powered by carbon-free electricity.

In 1991, the eruption of Mount Pinatubo in the Philippines injected huge amounts of sulfur dioxide into the stratosphere.

Also, current levels of carbon dioxide in the atmosphere are the highest for two million years, and the amount of methane and nitrous oxide are at their highest levels for 800,000 years.

But there’s also a third, hugely important player: the respiratory system, which acquires oxygen and gets rid of carbon dioxide.