This is a useful way to put carbon dioxide in the Earth's atmosphere into perspective (something sorely lacking in the current debate about climate change).
Of course these gases are mixed together in the atmosphere, which is why you should ignore anybody or any organisation that talks about the planet being smothered by a "blanket" of CO2. There is literally no such thing. And most of what is there is naturally occurring.
From Andrew Bolt:
Michael Smith‘s editorial on 4BC yesterday seemed to go down very well: