Global carbon dioxide emissions hit new record this year. What’s “fair” when it comes each country’s share of emission?

We know that the global CO2 emission will hit a record this year. We know that this is harmful to the environment. But we also know that some countries are emitting more CO2 than others. What would be considered “fair contribution” when it comes to emission? The average American or Australian generates ~3.5X the global average of CO2. Check out these articles regarding discussion on this matter.