Transport is currently responsible for around a quarter of UK total anthropogenic CO2 emissions and this proportion is projected to increase. The transport sector will undoubtedly need to play a significant role in achieving carbon reductions if the Government is to meet its ambitious long termgoal of a 60% reduction by 2050. This paper reports on a research projectwhich aims to examine the effects of personal transport activity in a major city on emissions of carbon. One of the key challenges facing policy makers is how to translate national policy towards carbon reduction to a more local level, in particular how best can such policy be implemented at a city level in order to bring about real reductions. Urban areas are often both concentrations of climate vulnerability as well as major consumers ofcarbon, while the concentration of activity in such relatively small areas gives a high potential for the development of innovative solutions, perhaps more so than elsewhere. The focus of this study is on personal travel in London and it provides a unique insight into the role that cities play in generating carbon emissions from transport and the kinds of policy instruments which could be used to effectively promote change in the ways thathouseholds choose to use the transport options available to them. The issues involved in defining the scope of travel associated with London and how carbon emissions were allocated are discussed. The difficulties of allocation when considering a finite geographical area such as a city are considerable, in particular how to identify and allocate emissions from the large number of work, shopping and leisure trips into the city from outside and those which are made by people from within the city outside of the boundaries. Consideration is also given to the issue, crucial for cities such as London, of how best to include the emissions from the large number of tourist related trips made by those from outside of the city. The key tool used in this research was a computer based carbon calculator developed to investigate household carbon emissions from their personal transport activity using travel diary information. In this research the calculator was adapted so that household travel diary information obtained from the UK National Travel Survey (NTS) could be used, giving access to large sample sizes, even where a sub-region of the country is considered. The use of diary data in this manner is novel and that collected through the NTS is highly detailed and sufficient to supply a good enough overview of transport activity to permit the modelling of carbon emissions. Building up a picture ofcarbon emissions from travel associated with London has been done in two key stages. Firstly, the emissions patterns of households living within the greater London area have been estimated from their travel data. This includes carbon emitted from travel wholly within the London area and also from travel to destinations outside London. For the latter travel an estimate of the carbon emissions for only the element of travel within the Londonarea has been made. In this stage the spatial disaggregation of the data means it has also been possible to explore differences in emissions characteristics between households living in inner and outer London. The second stage of analysis considered the emissions of carbon within the London area caused by travel from households who live outside of London, but who travel into the area. As before, only the element of travel within the Londonarea is used to estimate carbon emissions. Between them these two elements give an overall estimate, for the sample, of carbon emissions associatedwith personal travel occurring in London. The range of policy levers which could be used to reduce carbon emissions from transport associated with London are examined and the carbon calculator software models are used to investigate how effective they could be in terms of moving London towards a more sustainable transport system. Consideration is given to the effectiveness of both national and London based policy levers and also their relative effectiveness in promoting more sustainable travel amongst different groups of households. For the covering abstract see ITRD E137145.
Abstract