One could take a sample "good" and incinerate it, and measure the concentration of various greenhouse gases.

For services, the entire carbon content of the inputs is released as the inputs are consumed.

Now I'm thinking that in this model cow farts are a good way to avoid taxation. So if the carbon tax were high enough it would become economically efficient to use animals instead of motor vehicles for agricultural work and local transport. It would be an amusing return of the horse and ox economy.

Can the last politician to go out the revolving door please turn the lights off?