[Terr_]

In some cases it still is, but we need to emphasize the exceptions, which can be rather serious.

For example, we can hardly "dilute" CFCs or CO2 any more than we did, by putting them into a whopping 5.15×10^18 kg of the entire atmosphere of the Earth. Yet both still cause bad things, because there's no (sufficient) process to break them down or move them to a safe state.

[xg15]

Is that so? The amount of atmosphere stays the same, but we're constantly adding more CO2. So wouldn't this continually reduce the dilution?

[ta988]

the volume of CO2 is negliglible (ppms) and it uses often Oxygen from the air.