Controling O2 Instead of CO2

Instead of seeking, in order to avoid a threatening global overheating, to directly control emissions of carbon dioxide one way or the other (which has shown to not be so easy), one may ask if instead indirect control through the consumption of oxygen could be more effective.

Without O2 there will be no CO2.

The control could easily be effectuated by equipping each person with oxygen tubes with a certain ration per day. When the daily ration is consumed one would simply have to stop breathing until the next day. Simple and effective.