We are talking about CO2 emissions, not particle pollution. Since CO2 emissions are 1:1 related to fuel consumption, the fair, straightforward and easy way to d

We are talking about CO2 emissions, not particle pollution. Since CO2 emissions are 1:1 related to fuel consumption, the fair, straightforward and easy way to discourage excess emissions is to raise taxes on fuel. (Depending on political preference you might choose to cut other taxes with the revenues, or refund them equally per capita or reduce the deficit.)