It's just a theory, but I liked that simplicity.
New world currency will not be some central bank crypto replacement of fiat money, it will be carbon footprint units.
Price of everything will be nominated in carbon footprint units.
Each citizen will be given (monthly?) a fixed amount of that carbon footprint points he could spend on goods and services.
So, UBI, paid by authorities in carbon footprint units CBDC will effectively control citizens in the name of climatehoax with all shitty consequences.
Just like that.
Without question, but this is an oversimplification.
The complete analysis of all items consumed will be tallied and a variety of important totals will be used to restrain and restrict ones ability to exceed the accepted allotment.