[holding answer 24 January 2008]: Without accounting for the impact of policy measures, analysis suggests that emissions of carbon dioxide from UK transport would continue to increase to 2020. However, by implementing the policy measures quantified in the 2006 Climate Change programme and the 2007 Energy White Paper, domestic emissions from transport are projected to be up to 20 per cent. lower in 2020 than they would have been in the absence of these measures.
Because of the uncertainty of long-term forecasting, the Government have constructed a number of scenarios to model the costs of achieving long-term emission reductions. In the central scenario from the UK “MARKAL-Macro” model reported in the 2007 Energy White Paper, (under which the UK achieves a 60 per cent. reduction in domestic CO2 emissions by 2050), the transport sector sees emission reductions from 2000 levels of about 5 per cent. by 2020, and of about 45 per cent. by 2050.
The results of this model are not “forecasts”; the model presents the most cost-effective way of achieving the target in 2050, given, for example, an analysis of what technology can in principle deliver.