You buy some piece of land, or (as per TFA) lease it for 30 years. Then, you do nothing with it.
On the basis of you having the potential of doing something with it, you calculate a hypothetical difference in "potential scope of hypothetical activity" somehow denominated in the CO2 unit. The exact procedure for doing this is neither known, reproducible, nor audited?
This purely fictional "measure" (for lack of a better term) is then renamed to "credits" and converted to some monetary unit, like, say USD. The exchange rate is then what? And why?
Last, you sell - as in actually sell - this purely fictional nothingness to states and big corporations who all have multiple economists and/or scientists employed. Plus ample access to external specialists if their own capacities should somehow need a reality check...
Is it me, or does this seem a bit weird (to put it politely)?