I've been pointing this out for a long time. The switch to referencing "carbon" was a clear attempt to deceive by conjuring mental images of smokestacks belching out black smoke and soot. This went hand-in-hand with the climate charlatans also referencing carbon dioxide (sorry, "carbon") as "air pollution."
If the "science is settled", and this is all just basic scientific fact, then why the devious deception campaign?