META THEME PAPER

Journal of Transport Geography 19 (2011) 1538–1546

Contents lists available at SciVerse ScienceDirect

Journal of Transport Geography

j o u r n a l h o m e p a g e : w w w . e l s e v i e r . c o m / l o c a t e / j t r a n g e o

Cities, mobility and climate change

David Banister Transport Studies Unit, School of Geography and the Environment, Oxford University, United Kingdom

a r t i c l e i n f o a b s t r a c t

Keywords: Transport Cities Climate change Development

0966-6923/$ - see front matter � 2011 Published by doi:10.1016/j.jtrangeo.2011.03.009

E-mail address: [email protected]

Societies gain enormous benefits from travel, as economies have become more globalised and as the new communications infrastructure allows international networking and travel at a low cost. There has been a true internationalisation of all activities, and travel forms an essential part of that process. However, this mobility is fuelled by carbon, and there is clear scientific agreement that carbon emissions are affecting the global climate with irreversible long term consequences. Transport is the one sector where a reduc- tion in energy use and emissions is proving to be extraordinarily difficult to achieve despite some success in urban areas. This paper focuses on cities, mobility and climate change, highlighting recent trends in both developed and developing countries. It is argued that the current situation is unsustainable, and that transport must contribute fully to achieving carbon reduction targets. An alternative is presented, based on the sustainable mobility paradigm (Banister, 2008) that looks at ways to reduce the need to travel in cities. The belief that high mobility and technology provides the solution is misplaced, as technological innovation can only get us part of the way to sustainable transport, and this may facilitate more travel. There are opportunities for cities to switch to low carbon transport futures, where vision and action are based on a combination of economic, planning and technological innovations working in mutually sup- porting ways. Potentially, the future is bright for low carbon transport in cities, but the real question is whether there is the commitment and leadership to follow such a path.

� 2011 Published by Elsevier Ltd.

1. Introduction

There are enormous benefits from travel, as economies have be- come more globalised and as the new communications infrastruc- ture allows international networking at low cost. People’s aspirations and expectations have been increased through media coverage of world events, through more educational and leisure opportunities, and through increasing wealth. There is a true inter- nationalisation of all activities, and travel forms an essential part of that process. To counter that optimism is the evidence that we now live in the carbon society, and that carbon emissions are affecting the global climate with irreversible long term consequences. Transport is the one sector where such a reduction in energy use and emissions is proving to be extraordinarily difficult to achieve.

In urban areas, there are many good examples of reductions in energy use in transport, principally through demand management (pricing, parking and access control, congestion charging), invest- ment in public transport, priority for walking and cycling, and a range of soft measures designed primarily to reduce the use of sin- gle occupancy cars. In addition planners have been active in creat- ing high quality local neighbourhoods, including innovative designs for housing and mixed use developments, and the concen- tration of development around public transport accessible loca-

Elsevier Ltd.

tions. In all cases, the intention is to reduce the need to travel (particularly by car), to encourage greater use of public transport (and walking and cycling), and to reduce travel distances. The key here is to provide quality, with easy access to local services and facilities, so that people do not need to travel long distances. There are positive signs that city living is becoming ‘fashionable’ and that sustainable lifestyles are being adopted by many people (Banister, 2005).

This paper focuses on cities, mobility and climate change, high- lighting recent trends in both developed and developing countries. It is argued that the current situation is unsustainable, and that transport must contribute fully to achieving carbon reduction tar- gets. An alternative is presented, based on the sustainable mobility paradigm (Banister, 2008) that looks at ways to reduce the need to travel in cities. The belief that high mobility and technology pro- vides the solution is misplaced, as technological innovation can only get us part of the way to sustainable transport, and this may facilitate more travel. Evidence for making much stronger use of the planning and land development policies in combination are cited for cities in both developed and developing countries, and the argument is made for the use of all available policy levers in mutually supporting ways, including economic, planning and tech- nological opportunities. Potentially, the future is bright for low car- bon transport in cities, but the real question is whether there is the commitment and leadership to follow such a path.

Table 1 EU27 energy consumption and GHG emissions in transport and growth in travel (1990–2005 – data indexed to 1995 = 100). Source: EC (2006) and EC DG for Energy and Transport (2008).

EU27 Total energy consumption in transport (mtoe)

GHG emissions from transport activities (mtCO2e)

Travel by car (m pass km) All passenger travel (m pass km)

1990 2000 2005 1990 2000 2005 1990 2000 2005 1990 2000 2005 93 113 121 93 113 123 88 111 117 90 111 118

Notes: 1. Total energy – all modes, including rail, road, air and inland navigation. 2. Aggregate emissions of Kyoto basket of 6 GHG weighted by their global warming potentials. 3. All passenger transport includes car, bus, metro and rail, but not internal air, sea and powered two wheelers.

D. Banister / Journal of Transport Geography 19 (2011) 1538–1546 1539

2. The reality in the EU

In most EU cities, there are some indications that modest change in behaviour has taken place. The real challenge is not the acceptance of the strong links between mobility and climate change, but the imperative for substantial behavioural change. The scale of the prob- lem has been totally underestimated, and the actions being taken by governments at all levels are not addressing the seriousness of the issues. Even the actions taken by the most environmentally aware individuals are not sufficient, as it has proved very difficult to stabi- lise the level of carbon emissions from transport, let alone reduce them (Table 1). Since 1990, there has been a steady increase in en- ergy, emissions and travel in the EU27, and the pattern seems to sug- gest that the increase in energy and emissions is growing at a faster rate over this period than travel.

Even though schemes have been implemented to reduce the use of the car in cities and to make its use more efficient elsewhere, there has still been a substantial growth in travel distance, as cities have spread and as the desire for low density car based lifestyles has become dominant. The technology has not kept pace with the growth in car based travel, and even a substantial shift to more efficient vehicles and alternative fuels will not address the prob- lems fully. Over the next 25 years, it has been estimated that the maximum (possible) contribution of technological innovation to reducing CO2 emissions in the transport sector in the UK would be about 21MtC (to 2030) (Banister and Hickman, 2006). This is about half the levels required to achieve a 60% reduction, equiva- lent to the targets set by the IPCC over the longer period to 20501 (IPCC, 2001, 2007).

Such a change would require the ‘average’ cars to have an emis- sions profile of 90 gCO2/km, which is less than the current bench- mark level of 104 gCO2/km (Toyota Prius and Citroen C1), with half the fuel that is still needed by these vehicles being sourced from second generation biofuels. The current average level of emissions of new cars in the UK (2005) is 169 gCO2/km (SMMT, 2006). Similar changes would be required in all EU countries. Massive investment would be required in changing production processes for the new super efficient cars, in sourcing substantial quantities of alternative fuels, and in giving incentives to industry and individuals to use these new vehicles. Perhaps the only way to achieve such a change would be to switch to electric city vehicles, but even here there would need to be a new support infrastructure, and the power would have to be generated from renewable sources.

Significant reductions of CO2 emissions in transport in the EU can only be achieved through behavioural change. There is little sign that people are aware of the scale of the challenge, or prepared to make the necessary changes. Globally, carbon emissions per ca- pita are about 4.37 tCO2 (2006) (1.07 tCO2

2), but the EU27 average

1 Note that the 60% reduction figure is that required by the IPCC to achieve the stabilisation of carbon emissions by 2050, but brought forward to 2030 (IPCC, 2007 and Stern, 2006). The UK government has set itself an 80% reduction target by 2050, so this figure is consistent (Committee on Climate Change, 2008). It also assumes that transport should take a ‘fair’ share of the target reductions.

2 The figures in brackets give the estimated levels of carbon dioxide emissions from the transport sector.

is about 9.28 tCO2 (2.53 tCO2) and the US figure is 19.45 tCO2 (6.80 tCO2). The stabilisation targets mean that the average per capi- ta level should be under 2tCO2 (2050) (0.75 tCO2), much less than the current EU or US levels. It is also lower than the current level of 4.07tCO2 for China (0.45 tCO2) and about double the current level of 1.07 tCO2 in India (0.10 tCO2). This means that those countries currently producing more than the average levels of carbon emis- sions should be making an even greater contribution to the overall reduction target. The EU and the US should be leading the move to- wards contraction and convergence on this ‘stabilisation’ target (Meyer, 2001). Transport can and should play a major part in achiev- ing the target.

3. The global perspective

In addition to the denial of the scale of change required, there are other difficulties in achieving sustainable transport. The US produces over 21% (2006) of the carbon emissions from energy (including transport), yet it is not part of any international agree- ment to reduce its emissions (EC DG Energy and Transport, 2008). Over the last ten years it has increased its CO2 emissions by 14%, with global levels of CO2 increasing by 24% (1995–2005). Although only 5% of the world’s population live in the US, it has 30% of the cars and produces 45% of global car based CO2 emissions (DeCicco and Fung, 2006). It is crucially important that the US is fully engaged in the international debates about reducing levels of carbon emissions. The American Recovery and Reinvestment Act (2009) has allocated more than $80 billion to the generation of renewable energy, investment in clean technology, advancing vehicle and fuel technologies, and building a smarter electric grid, and there are new efficiency standards for cars and trucks.3 It is only very recently that the US motor industry seems to have become more aware of the need to produce a range of fuel efficient vehicles.

The global power structure is also changing, as has been seen at the Copenhagen Climate Change summit (COP15, December 2009), where for the first time China, India, Brazil and South Africa (the BASIC countries) have played a key role in determining the nature of the ‘Accord’ and the scale of the financial support for the poorer nations.4 But there were no binding commitments made, and trans- port was not mentioned either at the summit or in the ‘Accord’, even though this sector accounts for more than 23% of energy related glo- bal GHG emissions (Ribeiro et al., 2007).

The outlook is brighter at the city level, as many local govern- ments have taken on a leadership role in addressing the transport problems as they relate to carbon emissions, but there is consider- able variation between cities. For example, more than half the total energy consumption in Mexico City, Hong Kong and Cape Town is transport based (UN Habitat, 2008), whilst the level in many Euro-

3 The National Fuel Efficiency Policy (2012–2016) requires an average fuel economy standard of 35.5 mpg in 2016, and will save 1.8 billion barrels of oil over the life of the programme. The fuel economy gain averages more than 5% per year and will result in a reduction of approximately 900 million metric tons in greenhouse gas emissions.

4 The COP15 Accord can be downloaded http://www.denmark.dk/NR/rdonlyres/ C41B62AB-4688-4ACE-BB7B-F6D2C8AAEC20/0/copenhagen_accord.pdf.

1540 D. Banister / Journal of Transport Geography 19 (2011) 1538–1546

pean cities (for example, London and Paris) is about a quarter. This reflects the different strategies adopted by city planners over the recent past, such as promoting the use of the car through invest- ment in roads and free parking, to demand management and con- straints on the use of the car, and investment in local facilities and in public transport.

The politics are much wider than just the transport elements, as there are substantial income differences within and between cities, and not all people have access to transport. The UN Habitat (2008) review of world cities placed Beijing as being the most equal city in Asia (Gini coefficient5 0.22), but Hong Kong (also in China) has a much higher level of inequality (Gini coefficient 0.53). Recent analy- ses suggest that India is undergoing an inequality trend somewhat similar to that of China as a result of liberalisation and globalisation. In 2002, the income gain in the richest 10% of the population was about four times higher than the gain of the poorest 10% (UN Habi- tat, 2008). Investment in most transport infrastructure and services benefits the rich and not the poor.

6

4. Mega-cities and sustainable transport

Urban living will be at the centre of most activity, as over 50% of the world’s population are now classified as urban dwellers (2005). There is a clear expectation that this figure will increase to 70% by 2050. These levels of urbanisation are already apparent in Europe, North America and Latin America (UN Habitat, 2008). Globally, the rate of urbanisation is now 3 million per week (UN Habitat, 2008). Mega-cities (population over 10 million) are all characterised by high population growth, both from natural increase and through inward migration, and a huge expansion in the urban area with substantial new requirements for both housing and jobs. The rate of increase in the supply of new infrastructure will never match the growth in demand.

These cities have tremendous potential for growth and will be the powerhouses of the world economy over the next decades, but they are also centres for potential unrest, as there is substantial inequality and poverty (UN Habitat, 2008). The challenges for gov- ernments are daunting with little space for expansion in the origi- nal cities, so there is extensive urban sprawl with increased distances between where the people live, their jobs and other facil- ities. The concept of single centred cities is becoming less relevant with the growth in mega-cities, as they are rapidly developing as polycentric urban agglomerations, often absorbing other smaller cities in the process.

There is a fundamental difference between the priorities in high income cities, where the main concerns are over levels of pollution and consumption related burdens, and those in low income cities, where the concerns are more short term and health related. Their requirements include clean water, electricity, waste management and sanitation. All cities contribute to global emissions, but the de- sire for economic growth seems to be overwhelming, and this imperative often takes precedence over other priorities, and the net effect is a continuing growth in local emissions (NOx, CO, HC, SO2, PM10, and PM5) and global emissions (CO2). The high income cities have the opportunity to substantially reduce emissions through investment in clean technology and much greater energy efficiency, including a switch to low carbon energy. For the low in- come cities, the challenges are even greater, as they have other pressing social needs to address, but even here there are opportu- nities to switch to efficient low carbon energy sources.

5 The Gini coefficient is the most widely used measure to determine the extent to which the distribution of income or consumption among individuals or households deviates from a perfectly equal distribution. A Gini coefficient of 0 indicates perfect equality and a Gini coefficient of 1 indicates perfect inequality. http://www.scribd.- com/doc/328232/United-Nations-Gini-Coefficient.

There are good examples where development has been seen as investment, with the basic infrastructure being provided as part of the urbanisation process, as in Guangzhou City (Pearl River). Con- versely, higher densities can be achieved through compactness and integrated approaches that combine investment in high capacity public transport and development, as in Hong Kong or Singapore (around their metro systems) or in Curitiba (around its bus rapid transit system). Strong city level governance is essential, where there is a clear vision about the future of the city, and where there is both the power and resources for action. But above all, there is a need for leadership and for all stakeholders to engage with the pro- cess of city-building, so that responsibilities and actions are both supported and implemented effectively. This is the only way to move towards the sustainable city. The alternative is one of weak governance, where there is no direction and the consequences are huge sprawling divided cities – this is the inefficient and unsus- tainable city.

In Europe, there are no mega-cities, the possible exception being London, where the city region has a population of 15 million (25% of national population) and 40% of the GDP. The key concerns here are quality and sustainability that cover equality of opportu- nity, and access to services and facilities, as well as high environ- mental standards. Here, the growth rates are modest and there are strong governance structures that encourage order, priority for people, polycentric urban form (London is a city of villages), and the full integration of land use and transport.

Many of the World’s great cities are located on the coast or along the major rivers, as historically they have been centres of trade. But these locations are now prone to flooding, caused by storm surges and high winds, and accentuated by global warming (+2 �C) and sea level rise.6 About 40% of the World’s cities (1–10 mil- lion) and 15 of the 20 mega-cities lie on the coast. Their vulnerability to flooding has been substantially increased, and some have taken action to reduce the potential impacts, but 40 million or 10% of the total population are exposed to a 1 in 100 year coastal flood event, and this will rise to 150 million in 2070 (Table 2 and Nicholls et al., 2008). It is proposed that apart from upgrading protection and infrastructure to handle such events, land use planning should be used to reduce vulnerability for new developments and selective relocation of existing city areas should be considered. For example, London’s flood barrier was built (1974–1983) at a cost of (£1300 mil- lion in 2001 prices: $2000 million) to prevent flooding from high tides and sea surges for the ‘100 year event’. Between 1986 and 1996, the barrier was raised 27 times, but in the period 1996– 2006 it was raised 66 times. The expected property damage is esti- mated at £30 billion ($50 billion in 2001 prices) should the barrier be breached, and these financial costs do not include loss of life, health and income effects.

5. The sustainable mobility paradigm

Sustainable mobility provides a new paradigm within which to investigate the complexity of cities, and to strengthen the links be- tween land use and transport. The city will provide the location where most (70–80%) of the world’s population will live (2050). Empirical research in developed cities has concluded that the key parameters of a sustainable city are that they should be over 50,000 population, with medium densities (over 40 persons per

CO2 concentrations are currently about 385 ppmv and with other greenhouse gases being included, this value increases to 430 ppmv CO2e (2009). A level of 450 ppmv CO2e means that there is a 26–78% chance of exceeding 2 �C. A level of 550 ppmv CO2e means that there is a 63–99% chance of exceeding 2 �C. If global concentrations of greenhouse gases stabilise at 560 ppmv CO2e, it is ‘likely’ that global mean surface temperatures will rise by 3 �C above pre-industrial levels (Meinhausen, 2006).

Table 2 Potential impact of climate change on the top 20 world port cities. Source: Based on Nicholls et al. (2008).

2005 2070

Top 10 cities by exposed population

Top 10 cities by exposed assets

Top 10 cities by exposed population

Top 10 cities by exposed assets

Mumbai Miami Kolkata Miami Guangzhou New York–

Newark Mumbai Guangzhou

Shanghai New Orleans Dhaka New York– Newark

Miami Osaka–Kobe Guangzhou Kolkata Ho Chi Minh City Tokyo Ho Chi Minh

City Shanghai

Kolkata Amsterdam Shanghai Mumbai New York–

Newark Rotterdam Bangkok Tianjin (China)

Osaka–Kobe Nagoya Miami Tokyo Alexandria Tampa-St

Petersburg Hai Phong (Vietnam)

Bangkok

New Orleans Virginia Beach Alexandria New Orleans

These cities are split almost equally between developed and developing countries

These 10 cities account for 60% of total exposure, and are based in three wealthy countries (USA, Japan, and the Netherlands). Total exposed assets for all 20 cities is $3000 billion (2005 prices) or 5% global GDP

The exposed population has increased by three times to 150 m – almost all the cities are in developing countries

The total exposed assts have increased by 10 times to $35,000 billion (2005 prices) or 9% of global GDP

Note: The main driving forces of the 2070 scenarios are population growth, eco- nomic growth and urbanisation, and these factors are exacerbated by climate change (sea level rises and increased storminess) and subsidence.

D. Banister / Journal of Transport Geography 19 (2011) 1538–1546 1541

hectare), with mixed use developments, and preference given to developments in public transport accessible corridors and near to highly public transport accessible interchanges where densities would be substantially higher (over 80 persons per hectare) (Ban- ister, 2005). Such developments conform to the requirements of service and information based economies, and settlements of this scale would also be linked together to form agglomerations of polycentric cities, with clear hierarchies that would allow a close proximity of everyday facilities and high levels of accessibility to higher order activities (Hall and Pain, 2006).

Such urban forms would keep average trip lengths to below the thresholds required for maximum use of cycle and walk modes. It would also permit high levels of innovative services and public transport priority, so that the need to use the car would be mini- mised. Through the combination of clear planning strategies, cities would be designed at the personal scale to allow both high quality accessibility and a high quality environment. The intention is not to prohibit the use of the car as this would be both difficult to achieve and it would be seen as being against the notions of free- dom and choice. The intention is to design cities of such quality and at a suitable scale that people would not need to have a car.

This alternative approach requires clear and innovative thinking about city futures in terms of the reality (what is already there) and the desirability (what we would like to see), and the role that transport can (and should) play in achieving these objectives. The sustainable city must balance the requirements along the physical dimensions (urban form and traffic) against those concerning the social dimensions (people and proximity), as illustrated in Table 3.

The sustainable mobility approach requires actions to reduce the need to travel (less trips), to encourage modal shift, to reduce

trip lengths and to encourage greater efficiency in the transport system. A sustainable transport system means that we will travel less.

5.1. Reducing the need to travel – substitution

In its pure form this means that a trip is no longer made, as it has either been replaced by a non-travel activity or it has been substituted through technology, for example Internet shopping. The impact of information and communications technologies (ICT) on transport is complex, and on balance it seems that there is complementarity between these two factors (Banister and Stead, 2004). Although there is a large substitution potential, the relation- ships between transport and ICT seem to be symbiotic with a greater opportunity for flexibility in travel patterns, as some activ- ities are substituted, whilst others are generated, and some re- placed by fewer longer distance journeys (Lyons and Kenyon, 2003). There is also the possibility of carrying out a ‘trip tour’, where several activities are engaged in so that one longer journey replaces three or four shorter single activity trips. There is a net reduction in travel distance. Technology and networking in its wid- est form facilitates many different combinations of activities.

5.2. Transport policy measures – modal shift

Transport policy measures can reduce levels of car use through the promotion of walk and cycle and the development of the new transport hierarchy (Table 3). This can be achieved through slow- ing down urban traffic and reallocating space to public transport, through parking controls and road pricing, and through making it easier to use public transport. Demand management is effective in restricting access and reallocating space, and making better use of the available capacity. A much wider notion of the street is being created, as it is no longer only being considered as a road but also as a space for people, green modes and public transport. Creative use of that space at different times of the day or day of the week means also that new uses can be encouraged (e.g. street markets or play zones). Measures to encourage modal shift must be combined with strategies to make the best use of the ‘released space’, so that there is a net reduction in traffic (Banister and Mar- shall, 2000). This does not mean that more road capacity needs to be built, but that greater flexibility in its use is required and a greater proportion allocated to walk, cycle and public transport.

5.3. Land use planning measures – distance reduction

These measures address the physical separation of activities and the means by which distance can be reduced. The intention is to build sustainable mobility into the patterns of urban form and layouts, which in turn may lead to a switch to green modes and public transport. It is one area of public policy where interven- tion can take place, through increasing densities and concentra- tion, through mixed use development, through housing location, through the design of buildings, space and route layouts, through public transport oriented development and transport development areas, through car-free development, and through establishing size thresholds for the availability of services and facilities (Section 6). The timescale over which sustainable mobility might be realised is similar to the turnover of the building stock (about 2% per annum), but decisions on the location of new housing and retrofitting of existing buildings in new uses could have a dramatic effect on tra- vel patterns, and these effects will impact over the lifetime of that housing.

Table 3 Contrasting approaches to transport planning. Source: Adapted from Marshall (2001), Table 9.2.

The conventional approach

An alternative approach

Transport planning and engineering

Sustainable mobility

Physical dimensions Social dimensions Mobility Accessibility Traffic focus,

particularly on the car

People focus, either in (or on) a vehicle or on foot

Large in scale Local in scale Street as a road Street as a space Motorised transport All modes of transport often in a hierarchy with

pedestrian and cyclist at the top and car users at the bottom

Forecasting traffic Visioning on cities Modelling approaches Scenario development and modelling Economic evaluation Multicriteria analysis to take account of

environmental and social concerns

Travel as a derived demand

Travel as a valued activity as well as a derived demand

Demand based Management based Speeding up traffic Slowing movement down Travel time

minimisation Reasonable travel times and travel time reliability

Segregation of people and traffic

Integration of people and traffic

Table 4 Elasticities of trips and travel by land use factors. Source: Ewing and Cervero (2002).

Factor Description Trips Travel (VMT)

Local density Residents and employees divided by land area

�0.05 �0.05

Local diversity

Jobs/residential population �0.03 �0.05

Local design Sidewalk completeness/route directness and street network density

�0.05 �0.03

Regional accessibility Distance to

other activity centres in the region

– �0.20

1542 D. Banister / Journal of Transport Geography 19 (2011) 1538–1546

5.4. Technological innovation – efficiency increase

The role of technology is still important, as it impacts on the efficiency of transport directly through ensuring that the best available technology is being used in terms of engine design, alter- native fuels, and the use of renewable energy sources. The city car technology is likely to be based on a small highly efficiency ICE (Internal Combustion Engine) or an EV (Electric Vehicle or Plug- in Hybrid Vehicle). There are also considerable opportunities for new forms of public transport, for example in suburban areas where Demand Responsive Transport and even Personal Rapid Transit might play a key role. Technology could be used to provide a delivery service to local neighbourhoods or help organise car sharing schemes and car clubs. Holistic thinking on a low carbon city transport system is still embryonic.

Standards can also be introduced to reduce levels of noise and emissions at source, and measures can be taken to ensure that ac- cess to certain parts of the city are restricted to those vehicles that are environmentally cleaner than other vehicles. This is a combina- tion of technological efficiency and behavioural change (e.g. access restrictions, ecological driving and adherence to speed limits). It would also include increasing load factors in both the passenger and freight sectors, where again there are substantial opportunities to use the new technologies creatively to match up journeys or loads to increase occupancy levels and to reduce the overall num- bers of vehicles using the transport system.

The key to such a shift in thinking is the creation of spaces and localities in the city that are attractive and affordable, as neigh- bourhood quality is central to sustainable mobility. Transport plan- ning must involve all stakeholders in the broadest sense, so that there is an understanding and acceptance of the rationale behind the policy changes, and an increased likelihood that behavioural change follows. Such involvement would help match expectations of behavioural change with actual outcomes, and this in turn may lead to permanent change with limited possibilities for rebound ef- fects. Public acceptability is central to successful implementation

of radical change, and it needs to involve community and stake- holder commitment to the process of discussion, decision making and implementation.

6. Planning for city futures

Trying to unravel the complexities of the interrelationships be- tween travel, urban form and sustainable development is difficult. Underlying the discussion is the requirement to have some vision of the city in its desired form – it should be viable (economic jus- tification), have vitality (inclusive and fair), and it should be healthy (high quality of life and environmental quality). Transport provides an essential element in city viability, vitality and health. The EU vision is based on maintaining the quality of urban life, ur- ban planning and sustainable development, where mixed uses, high densities and good environmental conditions are seen as being central to both improving economic performance and the vitality of cities.

This vision has resulted from the assessment of the substantial research that has tried to establish the links between travel, land use and urban form. This research ranges from simple analyses of trip generation and attraction characteristics of particular land uses (e.g. residential and shopping) to more detailed analyses of travel (and energy use) in locations with distinctly different char- acteristics. The verdict on this empirical work is mixed. For exam- ple, Anderson et al. (1996) concluded that the current level of understanding of the influence of urban form on the generation of emissions and the use of energy is weak. But others (e.g. Stead, 2001; Hickman, 2007) have found far more significant relation- ships between land use and transport. In both these cases, the socio economic variables explain substantially more of the variation in trip making activities than the land use factors. Underlying all the debates, three main elements need to be examined, namely the density of development, proximity and quality of development, and local neighbourhood and design factors (for a more detailed exposition see Banister and Anable, 2009).

Land use effects on travel behaviour tend to be cumulative and mutually reinforcing (Hickman, 2007; Litman, 2007). This effect can be illustrated in two ways. Ewing and Cervero (2002) calcu- lated the elasticity of vehicle trips and travel per capita with re- spect to four land use variables (Table 4). Their estimates suggest that a doubling on local density reduces car trips by 5% per capita and travel by about the same amount. Although the elasticities are low, Ewing and Cervero (2002) concluded that they were cumula- tive, giving a total potential of 13% and 33% decreases in trips and trip distance (VMT) respectively.

The second study was by Lawton (2001) using data from Port- land Oregon to examine the impact of land use density, mix, and road network connectivity on personal travel. As these three

D. Banister / Journal of Transport Geography 19 (2011) 1538–1546 1543

urbanisation factors increase, per capita vehicle travel declines sig- nificantly from about 20 average daily travel miles per adult (32 kms) to just over 6 miles (10 kms).

From the extensive empirical work that has been carried out with respect to the impacts of the land use factors on travel distance, six main factors emerge (Banister and Hickman, 2006), and they are consistent with the sustainable mobility paradigm (Section 5). At the regional level, the location of new development, particularly housing, should be of a substantial size and located near to or within existing settlements so that the total population is at least 25,000 and probably nearer to 50,000. The provision of local facilities and services should be phased so as to encourage the development of lo- cal travel patterns. Secondly, density is important and average jour- ney lengths by car are relatively constant (around 12 km) at densities over 15 persons per hectare, but at lower densities car jour- ney lengths increase by up to 35%. Similarly, as density increases, the number of trips by car decreases from 72% of all journeys to 51%. Car use in the high density locations is half that in the lowest density locations. Thirdly, mixed use developments should reduce trip lengths and car dependence. Although research here is limited and concentrates on the work journey, there is considerable potential for enhancing the proximity of housing to all types of facilities and services. Fourthly, as settlement size increases, the trips become shorter and the proportion of trips by public transport increases. Diseconomies of size appear for the largest conurbations as trip lengths increase to accommodate the complex structures of these cities. Fifthly, development should be located near to public trans- port interchanges and corridors so that high levels of accessibility for all can be provided. But this may also encourage long distance public transport commuting. Free flowing strategic highway net- works are likely to encourage the dispersal and sprawl of develop- ment and stretch commuting. Finally, the availability of parking is a key determinant of whether a car is used or not and appropriate standards need to be linked to accessibility levels.

These conclusions have been confirmed in a report for the UK Commission for Integrated Transport (CfIT, 2009), where the six is- sues, as outlined above, have been extended to 11 factors that seem to be central when thinking about the role of spatial planning in con- tributing to sustainable development (Table 5). The UKERC (2009) has also produced a large review study of the options available for reducing carbon emissions from surface passenger transport, where each possibility is analysed according to their potential emissions saving, problems with implementation and their costs. The review concentrated on travel choices and vehicle choices, and their main conclusion was that behaviour could be influenced by a range of complementary policies and that carbon reductions can be achieved at a relatively low cost. Little was said in this study on the role that land use and spatial planning policies might play.

Litman (2007) has argued that in the US a 10–20% cumulative total saving in VMT is possible through density and mixed design, and a further 20–40% is possible from regional decisions on the location of new development (Table 6). The figures in the UK are likely to be less, as the trip distances travelled are lower and there

Table 5 Planning for sustainable travel – UK evidence.

1. Settlement size 5. Jobs-housing balance

9. Neighbourhood design and street layout

2. Strategic development location

6. Accessibility to key facilities

10. Traffic demand management

3. Strategic transport network

7. Development site location

11. Parking and servicing

4. Density 8. Mix of uses

Based on CfIT (2009).

is already a much greater use of land use and development controls than in the US.

In the US there is a clear recognition that the car has provided the means for cities to spread, leading to extensive suburbanisa- tion, longer travel distances and low densities (TRB, 2009). It is only recently that the costs of a car intensive lifestyle have become apparent, and it is now clear that compact, mixed use development has a beneficial effect on vehicle miles travelled (VMT) when it is combined with other policy measures, such as demand manage- ment (Table 7).

In the developed cities there is a key difference between the European and US traditions. In the European cities there is a history of strategic planning and the control of the land development pro- cess from the national to the local level, with clear priorities, responsibilities and controls. This strong planning environment has allowed cities to retain much of their historic structures and suburbanisation has also been controlled, and this has in turn meant that public transport has had a stronger role to play. In the US, much of the local zoning regulations restrict density levels and the mixing of land uses, and this presents a significant barrier to compact development (TRB, 2009). The potential for higher den- sity developments in the US is highest in new and replacement developments in the inner suburbs, and at locations near to good quality highway and public transport interchanges. The local con- cerns over congestion, local taxes and property values take prece- dence over the wider issues relating to housing affordability and climate change.

Cities in developing countries are following the same path, with the affluent middle classes buying cars as soon as they can afford to, and the resulting consequences for congestion, safety and the quality of the environment that are imposed on all other people in the city. The more efficient public transport, motorbikes and bicycles are squeezed out to make way for the car, which then dominates much of the available urban space. An opportunity has been missed, as it suggests that the car dominated US city is the only future. The EU cities offer a different perspective, as much of the existing urban structure has been maintained and there has been considerable investment in public transport. However, there is still the problem of urban sprawl, where both the land use and travel patterns are based on car dependent lifestyles and much lower density levels (Banister, 2006).

Cities that currently have low levels of motorisation are chang- ing out of all recognition. About half of the world’s population now live in urban areas, and this is increasing as migration takes place and as more city jobs are created. The Asian Development Bank estimates that the population of Asian cities are increasing by 40 million annually (ADB, 2009). Urban densities will fall as a result of increasing wealth, declining household size, low density resi- dential growth and central area redevelopment. Many of these cit- ies were not built for the levels of traffic they are now experiencing. The inherent flexibility in the use of street space for markets, small industrial activities and social spaces is being re- placed by traffic, so that the car can dominate. The car based mobil- ity requires mass redevelopment of the existing city centre or its expansion to new areas so that the necessary capacity can be cre- ated. Such ‘solutions’ are costly and have substantial implications for social welfare, environmental quality and health. The new mega cities of the world are emerging, not as the models of sus- tainable development, but as replicas of the car dependent cities of the West.

The ADB (2009) report has tried to address these issues through the promotion of a sustainable urban transport paradigm that examines management, finance and policy through a wide ranging review. Their proposal is for a much more transparent process that is built on accessibility, with demand management being seen as a central issue together with strong land use policy. The strategy is

Table 6 Land use impacts on transport – US evidence.

Factor Definition Travel impacts

1. Regional accessibility

Location of development relative to regional urban centres

Improved accessibility reduces per capita vehicle mileage. Residents of more central neighbourhoods typically drive 10–30% fewer miles than urban fringe residents

2. Density People or jobs per unit of land area

Increased density tends to reduce per capita vehicle travel. Each 10% increase in urban densities typically reduces per capita VMT by 1–3%

3. Mix Degree that related land uses are located close together

Increased land use mix tends to reduce per capita vehicle travel and increase the use of alternative modes, particularly walking. Neighbourhoods with good land use mix typically have 5–15% lower vehicle miles

4. Public transport accessibility, walking and cycling conditions

Quality of public transport and degree to which destinations are accessible; quantity, quality and security of walking and cycling

Residents with good access to public transport tend to own 10–30% less cars, drive 10–30% fewer miles, and use alternative modes 2– 10 times more frequently than residents in car oriented developments. Residents in more walkable communities walk 2–4 times as much and drive 5–15% less than if they lived in more car oriented developments

5. Centredness, network connectivity, design and management of routes

Location of employment in major activity centres, connectivity of the network (including density), design and layout of streets

Typically 30–60% of commuters to major commercial centres use alternative modes, compared with 5–15% of commuters at dispersed locations. Better road connectivity can reduce vehicle mileage and better cycling and walking provision also helps these modes. More multi modal streets improves use of alternative modes, with traffic calming reducing car use and increasing walking and cycling

6. Parking supply and management and site design

Number of spaces per unit area, costs, time limits and management, and layout considerations

Parking management strategies can significantly reduce car ownership and mileage. Cost recovery pricing reduces car trips by 10– 30%. Mobility management can also reduce car trips by 10– 30%

Based on Litman (2007), Table 21.

1544 D. Banister / Journal of Transport Geography 19 (2011) 1538–1546

based on looking at ways to avoid travel through shorter journeys and more accessible activities, to shift travel to public transport

rather than the car, and to improve the efficiency of all forms of transport. The avoid-shift-improve nexus is similar to the sustain- able mobility paradigm (Section 5).

There are two other key elements in the ADB (2009) proposals. There should also be a clear future city vision or spatial strategy that is affordable, adaptable and implementable, and this requires strong institutions and governance structures for the city. Sec- ondly, policy effectiveness needs to be clearly explained and ac- cepted by the full range of stakeholders, through their involvement in the process. This is a challenging agenda but one that must be addressed if cities are to become the real centres for sustainable development, as argued here.

The ownership of land in the city is the key factor in much of the discussion in this important paper (ADB, 2009). The case is made that for real change to take place, there needs to be direct interven- tion by city governments. It is only through stable public institu- tions that the location, scale and type of land development can be properly regulated and operated. Transport can be seen as part of that development where some of the benefits can be released through value capture. At present much of the land used by low in- come groups is negotiated through the informal and small land- owners, hence the need for intervention and partnership. It is only when the twin issues of poverty alleviation and sustainable transport are seen to be complementary and moving in the same direction that progress will be made.

7. Conclusions and implications for cities

The scale of the challenge is enormous, but it must be tackled in all cities, particularly those that are vulnerable to growth and flooding (Table 2). But the pathways followed by those cities in developed and developing countries may be rather different, as each city has its own unique problems to overcome. The debate on what to do also seems to have been set in a rather narrow eco- nomic framework that limits the possible role that planning and the land development process can play. For example, the McKinsey report (December, 2007) set a carbon abatement cost at $50 per tonne CO2e, and concluded that the US can reduce their emissions by between 3.0 and 4.5 Gt CO2e by 2030 (31–49% reduction). About a third of this figure would come from action on the built environ- ment (buildings) and transport, but it was assumed (p42) that there was no change in consumer utility. Urban design and denser, more transport efficient, communities were not assessed. It was also expected that there would be significant increases in distances travelled in the US over the period 2005–2030. The evidence cited here suggest that behavioural change and land use and develop- ment decisions can all have a substantial influence on travel and energy use, and must contribute to substantial reductions in CO2 emissions.

Although the empirical evidence may be limited, there is con- siderable potential for reducing the energy (carbon) use in trans- port in cities, through creative planning of new developments and the regeneration of existing areas. Sustainable development can be achieved through higher densities, high quality local envi- ronments, with close proximity to work and a range of services and facilities, in neighbourhoods that provide safety and security, so that the city can operate 24/7. Transport is designed out of much of the city, and where it is needed, priority is given to high quality public transport and cycling and walk. The role of the car in the city may be limited to ultra clean electric or plug-in hybrid vehicles powered by renewable energy.

Apart from the lack of a clear vision and the seductiveness of following the high mobility option, there are two other key obser- vations. One is that this option is extremely inequitable, as it fa- vours the rich that can afford the new mobility, and it creates

Table 7 Land use impacts on transport – US evidence.

The most reliable studies estimate that doubling the residential density across a metropolitan area might lower household VMT by 5–12%, and perhaps by as much as 25%, if coupled with high employment concentrations, significant public transit improvements, mixed uses and other supportive demand management measures

More compact, mixed use development can produce reductions in energy consumption and CO2 emissions both directly and indirectly Significant increases in more compact, mixed use development result in only modest short term reductions in energy consumption and CO2 emissions, but these

reductions will grow over time If 75% of new and replacement housing units are built in more compact development (effectively doubling densities) and the residents of compact communities drive

25% less, VMT and associated fuel use and CO2 emissions of new and existing households would be reduced by 7–8% relative to base conditions by 2030 and by 8– 11% by 2050. But there was some concern about whether such a substantial change was feasible

Based on TRB (2009).

D. Banister / Journal of Transport Geography 19 (2011) 1538–1546 1545

even greater problems for the mobility of other people. This is the classic situation where individual welfare is a much stronger force than societal welfare. The second is that to create change, there needs to be an alternative that is strongly supported by both the politicians and the public. Leadership and strong governance struc- tures are essential, so that longer term priorities are matched up with short term gains, and that investment and positive actions can be taken consistently over time. Unfortunately, these key ele- ments are often lacking in many cities.

This is the basic dilemma facing cities in terms of mobility and climate change. We all like travelling and we are doing much more of it. Yet we are also aware of the environmental costs of travelling and our responsibilities both locally and globally. Our social net- works are increasingly international and the global economy is also dependent on long supply chains. To some extent individual behaviour can be modified and we can substitute travel with tech- nological communication. But in many cases there is no substitute for face to face communication, and we want to see the world and to meet people. It presents a classic case of the conflict between individual preferences and choices, as opposed to the wider needs of society to protect the environment and future generations.

At present the scale and nature of the changes necessary in the transport sector to address climate change have not been seriously debated. Pricing for the external costs of transport would help, as would regulations on emissions and heavy investment in clean technology. But even here, the price rises necessary to create real change are not politically acceptable, as both industry and the elec- torate are powerful pro car lobbies. The real challenge confronting society is greater than this, namely the expected growth in travel from all cities and the desire for longer distance travel. Serious de- bate and action on these issues has not even started, and all the time the climate change clock is ticking.

Acknowledgments

Earlier versions of this paper have been presented at the Indian Institute of Technology, Delhi 2nd Annual TRIPP Lecture (March 2009), and at the Royal Geographical Society with the Institute of British Geographers’ Annual Conference in Manchester theme ses- sion on Transport and Climate Change (September 2009). Thanks also to two helpful referees.

References

Asian Development Bank (ADB), 2009. Changing Course: A New Paradigm for Sustainable Urban Transport, Manila, ADB, August.

Anderson, W., Kanaroglou, P., Miller, E., 1996. Urban form, energy and the environment: a review of issues, evidence and policy. Urban Studies 33 (10), 7–35.

Banister, D., 2005. Unsustainable Transport: City Transport in the New Century. Routledge, London.

Banister, D., 2006. Transport, Urban form and Economic Growth. Keynote Paper for the JTRC/ECMT Round Table 137, Berkeley, California, March, pp. 113–142.

Banister, D., 2008. The sustainable mobility paradigm. Transport Policy 15 (1), 73– 80.

Banister, D., Anable, J., 2009. Transport policies and climate change. In: Davoudi, S., Crawford, J. (Eds.), Planning for Climate Change: Strategies for Mitigation and Adaptation for Spatial Planners. Earthscan, London, pp. 55–69.

Banister, D., Hickman, R., 2006. How to design a more sustainable and fairer built environment: transport and communications. IEEE Proceedings of the Intelligent Transport System 153 (4), 276–291.

Banister, D., Marshall, S., 2000. Encouraging Transport Alternatives: Good Practice in Reducing Travel. The Stationery Office, London.

Banister, D., Stead, D., 2004. Impact of information and communications technology on transport. Transport Reviews 24 (5), 611–632.

Commission for Integrated Transport (CfIT), 2009. Planning for Sustainable Travel: Summary Guide, Report Prepared for the CfIT by the Halcrow Group, Oxford Brookes University and the University of Oxford, October. <www.plan4sustainabletravel.org>.

Committee on Climate Change, 2008. Building a Low-carbon Economy – The UK’s Contribution to Tackling Climate Change, London, December.

DeCicco, J., Fung, F., 2006. Global Warming on the Road: The Climate Impact of America’s Automobiles, Washington: Environmental Defense, June, p. 31.

European Climate Change Change Programme – EU Action against Climate Change, Brussels, January. <http://europa.eu.int/comm/environment/climat/pdf/ eu_climate_change_progr.pdf>.

EC DG for Energy and Transport, 2008. EU Energy and Transport in Figures 2007/ 2008, Luxembourg.

Ewing, R., Cervero, R., 2002. Travel and the Built Environment – Synthesis, Transportation Research Record 1780, TRB Washington.

Hall, P., Pain, K., 2006. The Polycentric Metropolis: Learning from Mega-City Regions in Europe. Earthscan, London.

Hickman, R., 2007. Reducing Travel by Design; A Micro Analysis of New Household Location and the Commute to Work in Surrey, Unpublished PhD Thesis, Bartlett School of Planning, University College London, November.

IPCC, 2001. Climate Change: The Scientific Basis. Oxford University Press, International Panel for Climate Change, Oxford. <www.ipcc.ch>.

IPCC, 2007. Climate Change 2007: The Physical Science Base, Report for Policy Makers, Paris, February. <http://www.ipcc.ch/SPM2feb07.pdf>.

Lawton, K.T., 2001. The Urban Structure and Personal Travel: An Analysis of Portland, Oregon Data and Some National and International Data, E-Vision Conference. <http://www.rand.org/scitech/stpi/Evision/Supplement/ lawton.pdf>.

Litman, T.A., 2007. Land Use Impacts on Transport: How Land Use Factors Affect Travel Behaviour. Victoria Transport Policy Institute, Canada, April.

Lyons, G., Kenyon, S., 2003. Social participation, personal travel and Internet use. In: Proceedings of the 10th International Conference on Travel Behaviour Research, Lucerne, August.

Marshall, S., 2001. The challenge of sustainable transport. In: Layard, A., Davoudi, S., Batty, S. (Eds.), Planning for a Sustainable Future. Spon, London, pp. 131–147.

McKinsey and Company, 2007. Reducing US Greenhouse Gas Emissions: How Much at what Cost? US Greenhouse Gas Abatement Mapping Initiative, December.

Meinhausen, M., 2006. What does a 2C target mean for greenhouse gas concentrations? A brief analysis based on multi-gas emission pathways and several climate sensitivity uncertainty estimates. In: Schellnhuber, H.J., Cramer, W., Nakicenovic, N., Wigley, T., Gohe, G. (Eds.), Avoiding Dangerous Climate Change. Cambridge University Press, Cambridge, pp. 253–279.

Meyer, A., 2001. Contraction and Convergence. Green Books, and available from the Global Commons Institute, London.

Nicholls, R.J., Hanson, S., Herweijer, C., Patmore, N., Hallegatte, S., Corfee-Morlot, J., Chateau, J., Muir-Wood, R., 2008. Ranking Port Cities with High Exposure and Vulnerability to Climate Extremes, OECD, Environment Working Paper 1, ENV/ WKP (2007). <http://www.oecd.org/env/workingpapers> (republished on 19.11.08).

Ribeiro, K.S., Kobayashi, S., Beuthe, M., Gasca, J., Greene, D., Lee, D.S., Muromachi, Y., Newton, P.J., Plotkin, S., Sperling, D., Wit, R., Zhou, P.J., 2007. Transport and its infrastructure. In: Metz, B., Davidson, O.R., Bosch, P.R., Dave, R., Meyer, L.A. (Eds.), Climate Change 2007: Mitigation. Contribution of Working Group III to the Fourth Assessment Report of the Intergovernmental Panel on Climate Change. Cambridge University Press, Cambridge, United Kingdom and New York, NY, USA, pp. 325–385.

Society of Motor Manufacturers and Traders (SMMT), 2006. UK New Car Registrations by CO2 Performance, London, April.

Stead, D., 2001. Relationships between land use, socio-economic factors, and travel patterns in Britain. Environment and Planning B 28 (4), 499–528.

1546 D. Banister / Journal of Transport Geography 19 (2011) 1538–1546

Stern, N., 2006. The Economics of Climate Change, Report for HM Treasury. October and also published by Cambridge University Press, London. <http://www.hm- treasury.gov.uk/independent_reviews/ stern_review_economics_climate_change/stern_review_report.cfm>.

Transportation Research Board (TRB), 2009. Driving and the Built Environment: The Effects of compact Development on Motorized Travel, Energy Use and CO2 Emissions, Transportation Research Board Special Report 298, August.

UKERC, 2009. What Policies are Effective at Reducing Carbon Emissions from Surface Passenger Transport? A Review of Interventions to Encourage Behavioural and Technological Change, UK Energy Research Centre.

UN Habitat, 2008. State of the World’s Cities 2008/2009: Harmonious Cities. Nairobi, UN Habitat – Kenya.