PASSENGER CAR GLOBAL WARMING POTENTIAL - CURRENT AND PROJECTED LEVELS IN THE UK

This paper presents the results of a new analysis of the global warming potential of emissions from passenger cars in the UK. Projections of future emissions are combined with GWPs to present a picture of the overall potential of future car transport emissions to affect the global climate. The projections from this modelling exercise point to the fact that the car transport sector will not be able to meet the international target of returning emissions of greenhouse gases to their 1990 levels by 2000. Technological improvements will help to keep in check the total warming impact of car transport in the near future by reducing non-carbon dioxide emissions. However, eventually demand increases will overcome this benefit unless further improvements, particularly in CO2 emissions, can be achieved. This suggests a need for prompt introduction of longer-term measures to manage demand and increase trip efficiency. The results of our sensitivity analysis suggest that more work to better determine nitrous oxide emissions factors should be given priority, that increasing diesel market share has little impact, and that the uncertainties over actual GWP values do not appear to have a significant impact on the total warming potential of passenger car emissions.