When we talk about CO[sub]2[/sub] production, we usually talk only about the burning of fossil fuels. Which makes sense, since something like 80% of carbon dioxide comes from them. But what about other sources?
As I understand it, most of the other 20% comes from industrial sources. The only one I know of is the making of lime (calcium oxide), which is made by heating limestone (calcium carbonate CaCO[sub]3[/sub]) to something like 800 C, at which point it breaks down to lime and carbon dioxide.
Well there’s lots of lime being made, since it’s an essential ingredient of cement, but are there any other significant industrial sources of CO[sub]2[/sub]?
Volcanic eruptions aren’t man-made, but it’s not burning fossil fuels either. They put out so much pollution (CO2 included) it’s been debated whether that’s actually the cause of climate change as opposed to humans causing it.
Isn’t dry ice made by condensing CO2 from the atmosphere?
(In which case, there’s no new CO2 being generated, except possibly to make the electricity to run the refrigeration units).
Well, not seriously debated. Climate change (and atmospheric CO[sub]2[/sub]) has skyrocketed since the start of the industrial revolution, but there haven’t been any more volcanic eruptions in that period than any other time in history. And in fact we know about how much fossil fuel we’ve burned, and how much the CO[sub]2[/sub] has increased, and the numbers correspond.