[bill1952]

CO2 output must cease altogether, studies warn ...

Okay. Just outlaw all catalytic converters and have them removed immediately from all cars on the road.

Make their manufacture illegal.
What do they convert again?

[AntiKev]

What do they convert again? Nitric and nitrous oxides to diatomic nitrogen and oxygen. Toxic stuff that basically produces nitric acid on contact with water and oxygen. Fun stuff. Nothing to do with CO2 though.