The carbon dioxide emissions associated with the energy required by the transportation sector of the world specified in six scenarios covering a wide range of possibilities formulated in a report of the World Energy Council/International Institute for Applied Systems Analysis (WEC/IIASA) were plotted on the assumption that all the energy required for this purpose originated from oil. Also plotted were the carbon dioxide emissions associated with four parabolic projections of world conventional oil production based upon the Year 2000 Resource Assessment of the U.S. Geological Survey. These in turn were compared with the sustainable value of emissions of this gas derived from the fossil fuels.

Two of the WEC/IIASA Scenarios with almost the same transportation energy requirements – C1 and C2 – remain below the sustainable limit of carbon dioxide emissions until after 2070. For the other four scenarios, transportation requirements exceed the limit in the years ranging between 2022-2043. All four cases for the projection of world oil production exceed the sustainable limit from 2037 at the earliest (Case 3) until 2067 at the latest (Case 4). The Mean Case 1 exceeds the limit until 2050. The supply of conventional oil can meet the requirements of the transportation sector (100% allocation basis) until 2026 at the earliest to 2069 at the latest.