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North American transportation: perspectives on research needs and sustainable transportation
Journal
PII:SO966.6923(96)00042-7
ofTmnspon Geogmphy Vol.
5. No. I, pp. 12-19. 1997 0 1997 Ekvier Science Lid All rights reserved. Printed in Great Britain 0966-6923197 $17.00+0.00
North American transportation: perspectives on research needs and sustainable transportation William R Black Department of Geography, Indiana University, Bloomington, IN 47405, USA
5% of Mexico’s area. From these perspectives Mexico is underdeveloped in a transport context. The North American Free Trade Agreement (NAFTA) has created the potential for significant changes in the US, Canada, and Mexico, and the interaction between these countries. For example, prior to the agreement Mexican trucks could not operate in the US (except in commercial zones of border cities) and US truckers could not operate in Mexico. As of December 18, 1995, truckers of each country will be allowed to obtain permits to operate in the other country for international cargo transport. Also included in NAFTA are provisions liberalizing the ownership of carriers in the participating countries. Rail transport is hardly touched by the agreement, and gauge differences in Mexico make transport interaction between it and the US and Canada im~ssible, although the latter two countries interchanged traffic even prior to the agreement. There have been numerous pieces of legislation enacted and executive orders signed that have attempted to improve different aspects of the transport system of the US and Canada. Among these the following would have to be recognized: the US National Environmental Policy Act of 1969 and its requirements for environmental impact assessments of federal transport projects; the US Clean Air Act of 1970 and its amendments, which have set limits on motor vehicle emissions and established CAFE (corporate average fuel efficiency) standards; and the US Intermodal Surface Transportation Efficiency Act (ISTEA) and its requirements for public transit, congestion, safety, intermodal and pavement managearea ment systems, and state and metropoIitan planning. As noted previously, Canada has also enacted legislation to improve air quality, vehicular emissions, and fuel efficiency standards. Mexico has been less active in this general area. In spite of the legislative activity, executive actions, and international agreements, there continues to be transportation problems in the US, Canada, and Mexico, and those problems are becoming larger and
The transportation system in North America is one of the most advanced in the world. For the most part it facilitates the movement of goods and people in a reliable, efficient and convenient manner. The quality of the highways, the rail systems, and the airline networks is of a high caliber. At the same time these networks are less dense in Canada and of a lower quality in Mexico, as compared to the US. The US has passed legislation over the past four decades to build a national interstate highway network, to decrease and then increase speed limits on the nation’s interstate highways, to subsidize public transit operations, and capital expenditures, to create a research, for-profit national rail passenger system, and to deregulate (1) railroad operations devoted to the movement of freight (Regional Rail Reorganization Act of 1973, Rail Revitalization and Regulatory Reform Act of 1976, and the Staggers Rail Act of 1980), (2) domestic intercity airline passenger systems (Airline Deregulation Act of 1978) (3) intercity bus operations, and (4) motor carriers (Motor Carrier Deregulation Act of 1982). Similarly, Canada has enacted legislation to deregulate much of its transport sector and to privatize public systems (Canadian National Railroad, Air Canada, and VIA Rail). On the environmental front there is a Clean Air Act and a Motor Vehicle Safety Act (with provisions to control emissions). Provincial agencies responsible for energy and the environment are currently trying to set higher motor vehicle fuel efficiency standards. There has been less transport legislation activity in Mexico. The country has a national railroad (Ferrocarriles Nacionales de Mexico), but there is little discussion about privatizing the system. There are about 6.5 million automobiles and 5 million motor carriers. These numbers are comparable to the motor vehicle fleet in Texas, a state with a population equal to about 20% of that found in Mexico. The highway network consists of 242 000 kilometers, but only about 49 000 kilometres are classified as main roads; this is comparable to the state of Kansas, with an area about 13
North American transportation: W R Black
more complex. In general the problems spread across the major areas of transport system attributes (intermodal transfers, infrastructure decline, congestion, security, safety, environmental impacts, and long-term fuel availability), traffic flow attributes (including trip characteristics, full costing of travel, travel market saturation, substitution of communication technology for travel), trip-maker attributes (including driver choice behavior and attitudinal change studies), and methods of analysis and planning (including project assessment techniques, new travel modes and analytical methods, including spatial-temporal analysis methods, neural networks, three-dimensional visualization, and virtual reality). The pages that follow present more detail on the transport problems identified and suggest some promising methodologies worthy of further analysis. This is followed by an attempt to synthesize and characterize the transport future envisioned for the first quarter of the next century. That future will resemble what currently exists, with the exception of a greater role for technology and a greater concern for the environment. It is seen within the context of a ‘sustainable transport future’, and the research activities identified here are directed toward assuring that future. Tkansport systems Intermodalism
NAFTA has moved toward significantly improving the movement of goods between the countries of North America. At the same time the most active growth area for the transport of goods is in the area of containers. The movement of these from ships to road to rail and perhaps back to trucks is still not as seamless as it could be. The use of scanning techniques for customs inspections is already in place, but what additional improvements could be made to improve the efficiency of these flows? Numerous geographic databases have been developed that depict the various transport networks of North America (e.g. rail, highway, and waterway). Most intermodal analyses require the use of a single intermodal network with comparable shipping costs, time spent in transit, transfer costs, and field definitions. Such a network needs to be created to examine intermodal flow alternatives and methods of working with intermodal or multimodal flows. Infrastructure
Without a doubt one of the major transport problems of today is maintaining and developing new infrastructure. Most of the first-generation rail transit systems in the US will require major investments in the next one or two decades. Highways and bridges are unable to endure the stress placed upon them by the heavier
13
trucks of the last two decades. Port facilities will have difficulty handling the new 5000 twenty-foot-equivalent container vessels. Investing in all of these facilities will require the development of new funding mechanisms and revenue sources. At the same time one is reminded of the statement by Garrison (1985) that ‘most frequently, the infrastructure problem is described as not enough money, and its solution is more money’. He goes on to suggest the need for more basic research on infrastructure systems, existing and new. This need has yet to be addressed. A related question is whether we should be considering a freight rail line to connect Canada with Mexico? The only connections being discussed today are highway connections. Given the length of this connection, a rail line connection is feasible.
safety In 1994 the highway transport system of the US _. claimed the lives of 40 676 motor vehicle users and pedestrians. This statistic is appalling in its magnitude, but the situation has actually improved over the last couple of decades. This is due in part to the required use of seat belts and other safety-related improvements, as well as more severe treatment of intoxicated drivers. Nevertheless, there is a need for further research to discern other causal factors and possible real-time systems that would alert users and safety officials of a developing problem. Security Transit systems in some urban areas are avoided because of the potential risk of criminal activity on those systems during evening hours. There is a need for research that would assess to what extent this is a real problem and to what extent it is a question of perception. To the extent that the problem is real, what feasible approaches exist to halt such activity? It should be apparent that transport modes may well become targets for acts of terrorism from those within or outside of North America. The air passenger system has had a long history of problems in this area. Can the railroad passenger and freight system transfer any of air transport’s approaches to their systems? Congestion
A problem of growing concern in North America is the increase in highway congestion that has occurred in the last decade (Transportation Research Board, 1994). In general, it is fairly certain that additions to capacity are not the answer to this problem (Transportation Research Board, 1995). That has been the approach during the second half of this century and it has simply resulted in more congested highways. We need to make sure that we are measuring the problem in an acceptable manner and then we must proceed to
14
North American transportation: W R Black
identify the contribution of different activities (traffic calming devices, staggered work hours, and so forth) in reducing congestion. It has been suggested that the US is approaching a saturation point with regard to male drivers using the system. Where does the female population stand in this regard? Will they become the primary reason for additions to congestion in the coming decades? Can anything be done to prevent this growth in congestion? Another congestion problem has become evident at several of North America’s airports, while other airports have excess capacity. This imbalance is attributable in part to the practice of hubbing, which results in significant traffic arriving and departing from hub facilities while non-hub airports have significantly Are there network optimization less activity. approaches that could evaluate the costs of using multiple hubs and their impact on congestion levels at different airports? While the merits of hubbing for the airline are obvious, it would appear that each airline passenger passing through a hub loses two hours of their time in comparison to those that use direct flights. This generates significant social and productivity costs. Environmental impacts Perhaps no single area is impacted more by transport than the environment. Every sector of the natural environment (water, vegetation, geomorphology, soils, animal life, and the atmosphere) receives negative impacts from various transport systems. In some cases there is little knowledge about the scope of these impacts, e.g. the impacts of transport on the movement or fatalities of animal populations. However, it should be apparent that the atmosphere is currently receiving the major negative externalities at this time. There are four major problem areas: urban air quality, ozone depletion, acid precipitation, and global warming. Researchers have been working with the development of models to evaluate transport impact on urban air quality for nearly a quarter of a century. A fundamental problem in this area is the lack of enough monitoring devices to measure the actual pollution occurring from the transport sector at a given point in time. A major air quality database for an urban area would facilitate model development in this area. The use of CFCs (chlorofluorocarbons) in automobile air conditioners have been a major contributor to the ozone depletion problem. Provisions of the Montreal Protocol as amended that brought a halt to the production of CFCs at the end of 1995 should help to reduce the magnitude of this problem. However, the alternative coolants developed to replace CFCs also bring along certain problems for the atmosphere. There are already some indications that this problem will be of less significance in twenty years, but what more can be done in the interim?
Acid deposition exists in most parts of the US, Canada, and Mexico, but it is a problem only in selected areas due to the low buffering ability of the soils there. Motor vehicles contribute to this problem through emissions of sulfur and nitrogen oxides. While the impacts of the resultant sulfuric and nitric acids are known in parts of the northeastern US and southeastern Canada, there has been little research into the potential impacts elsewhere, e.g. on structures or on surfaces that can rust or corrode. It is also not immediately apparent what the ‘atmospheric transport process’ is that takes motor vehicle emissions to the upper troposphere. The overwhelming scientific consensus is that the planet will undergo a warming attributable to emissions of what are called greenhouse gases, e.g. carbon dioxide, methane, CFCs, and nitrogen oxides, among others. The only questions of any merit today are exactly how much warming will occur and what will be the scope of its impacts on social and economic systems. Motor vehicles are a primary contributor of most of the recognized greenhouse gases. The major greenhouse gas is carbon dioxide; motor vehicles are responsible for nearly two trillion pounds of carbon each year in the US. How can we combat this problem, or have we already accepted its likelihood? Even if we completely halt the emissions of greenhouse gases, carbon would remain in the atmosphere for more than 100 years and any observed warming would continue for that length of time as well. What types of carbon emission trading systems might be worth examining for the transport sector? Fuel availability Many of the proposals for slowing down the global warming that is anticipated involve the use of alternative fuels (Nadis and MacKenzie, 1993; Ogden and DeLuchi, 1993; MacKenzie, 1994; Sperling, 1995). Several of these ‘new fuels’ are tied to petroleum, e.g. gasohol which may be 90% gasoline, oxygenated gasolines, and so forth. We seem to be ignoring the finite nature of petroleum-based fuels. Recent forecasts of known and expected petroleum reserves suggest that the world will run out of petroleum midway through the 21st century. It makes sense to begin looking at alternative fuels and systems and researching the feasibility of their large-scale development, adoption, and distribution. Accessibility impacts Congestion in some North American central cities has led to accessibility advantages on the edges of cities. What are the social and economic implications of these ‘edge cities’? Will this lead to a second major phase of suburbanization in the US and Canada? Beyond urban areas there are areas of the Canadian provinces and parts of Mexico that are inaccessible to
North American transportation: W R Black
the major transport lines nearest them. How can these often geographically remote areas be ‘connected’ to the rest of the system in a cost-effective manner?
15
proposals would be, and what mechanisms are needed to distribute the revenues generated. Travel market saturation
System valuation
Assessments of the value of transport systems often note the employment in that sector. If communication proves to be an acceptable substitute for transportation will this lessen the value of transport as a whole? If project improvements must demonstrate benefits for users (and benefits for non-users now in the UK), isn’t further expansion or rehabilitation of the highway systems in some parts of North America unlikely? If communication is an alternative for the journey to work, can the time savings for the latter trip be used to justify a highway investment? These topics certainly merit analysis. ‘Ikaffic flow attributes Improving the transport systems of North America will not solve all of its transport problems. For example, it is now recognized that the construction of additional highways or even the addition of capacity to existing highways will not eliminate highway congestion problems in the US. To do this there must begin to be some fundamental changes in the nature of tripmaking and travel behavior. This section examines some areas where change is both likely and necessary.
As noted above, it has been argued that aggregate congestion will not become much worse in the US because the male market for motor vehicles has nearly been saturated, i.e. additional cars would simply increase the ratio of cars to male drivers which is currently near unity. Research has tended to support these ideas. The inference is that if there is additional motor vehicle travel, and therefore congestion, it will
Table 1 ‘Ikansportation
costs
Accident costs Deductibles Productivity losses Value of life
Operating costs Fuel, oil Registration Licenses
Capital costs Highways, streets, runways, tracks Planning Land acquisition Preliminary engineering Construction Deferred investment Terminals and garages Vehicles (motor vehicles, aircraft, buses, etc.)
Parking-related costs Fees Fines Governmental (subsidized) Private residential
Congestion (see Time costs, Operating costs, and Pollution Fares
There is a great deal that we do not know about urban travel and trip-making behavior. Research has posited the existence of a frictionless zone for urban travel, but we know little more about this today than we did a quarter century ago. We have seen a growing recognition of trip-chaining, which is thought to better represent travel patterns. However, whether trips are chained or treated as individual trips from origins to destinations has no impact on their analysis. The notions of travel budgets and minimum travel requirements are also worth analyzing in more detail.
Highway-related governmental Services Police Fire Criminal justice
Several recent studies have made it very clear that the US, Canada, and, to a lesser extent, Mexico are indirectly subsidizing the cost of motor vehicle travel by allowing many of the costs generated by this mode to be covered by non-transport sectors (see Table I) (MacKenzie et al., 1992; Miller and Moffet, 1993; Litman, 1995). If these costs were included in the price of fuel, it would significantly decrease the demand for travel, decrease congestion, and provide funds for many of the external costs generated by this transport sector. There is a need to examine which costs should realistically be included, what the impacts of such
co;
co
Trip characteristics
Full costing of travel
Pollution Air Air quality NO.
Land-related costs Archaeological sites Historic buildings Loss of open space Loss of wetlands Urban sprawl
SPM SO, Urban ozone Acid deposition Stratospheric ozone depletion Climate change Long-term health Noise Structural Vibration damage Water Marine (spills) Runoff Property values
Loss and damage
Repair and maintenance Vehicles Facilities
Macroeconomic costs Balance of trade payments Inflation
Subsidies
Maintenance costs Grass cutting Snow removal Patching
Time costs Commercial Personal Transportation
equity
Manufacturing or refining Energy costs Resource use Military security for petroleum Source: William R. Black, Dean L. Munn, Richard J. Black and Jirong Xie (1995), Modal Choices: An Approach to Comparing the Costs of Transportation Alternatives, Transportation Research Center, Indiana University, Bloomington.
16
North American transportation: W R Black
be attributable to more women driving. However, there are also questions of where and when vehicles are used by men and women. Is this the real congestion problem? These ideas need to be examined in some detail.
actual changing of attitudes appears to be due more to marketing as opposed to education. In the historical highway tax case above, were chambers of commerce and highway construction interests behind the broad acceptance of that tax? Isn’t marketing simply a more aggressive form of education?
Substitution of communication It has long been argued that high-quali~ communications can result in the substitution of communication for travel. This may have happened on several occasions in the recent past, but the current emphasis on telecommuting or teleworking has begun to enliven this potential substitution effect. While estimates vary on the magnitude of this substitution effect, it may be substantial. We need better methods of estimating the potential scope of teleworking. Research is necessary to determine the types of employment that can make use of this communication option and the magnitude of the daily reduction in travel. Changes in information technology have already had a significant impact on commodity flows, warehousing, and industries’ over-reliance on the transport system, as best illustrated by ‘just-in-time’ delivery systems. This leads to inefficiencies in flow volumes and risks of flow inter~ptions. It is recognized that congestion in traffic flows is in part attributable to urban sprawl and low-density housing. It is disturbing to consider the footloose capabilities for housing ‘if communication links substitute for transport links. While there may very well be a decrease in the length of daily trip-making, the oncea-week trip to the office (often suggested as necessary for telecommuters) may consume more fuel than five daily trips. Research has shown that the length of time devoted to the journey to work has not changed much in recent years, but has tended to remain the same. Would one day trip have a length equal to the time of the previous five daily trips?
‘II-ip-maker attributes Changing attitudes There is a necessity for people’s attitudes toward transport solutions to change if we are to solve several transport problems. For example, the external cost of using motor vehicles is significant and generates costs that are not covered currently by motor vehicle taxes. At the same time there is a belief on the part of policymakers that any tax increase is unacceptable. This effectively rules out these types of policy solutions. We are reminded of the fact that all 48 states of the US enacted highway fuel taxes between 1919 and 1927. Historical research on the process of adopting these taxes might be very informative and assist us in understanding the process of adopting such measures. It may be argued that adoption of necessary changes takes place because of educational efforts, but the
Eip budgets Trip budgets are gaining more and more recognition as an influential determinant of travel behavior. It is also said that Americans drive too much, suggesting there is some optimal (minimal) level of travel. Would it be possible to develop a ‘minimum requirements approach’ to travel budgets so that we can at least talk about the levels of travel reduction that are possible? Should travel behavior be examined in the context of a total activity budget? If shifts are made to a four-day work-week, what would be the impact on travel? Family structure and travel demand There have been significant changes in the structure of the North American family, primarily in Canada and the US. There are increases in divorce, single parent households, and individuals living alone. The net result of these changes from a transport perspective is an increase in the number of trip-making units. What once could be accomplished by one trip-maker for a family, may now require two or three individuals. What other travel changes have resulted from these social trends? Age and trip-making There are two cohort groups of the population that are of concern with regard to motor vehicle safety. The first of these is the ageing driver. Estimates suggest that one out of five motor vehicle drivers in North America will be over the age of 65 in 2010. It is also known that, after age 55, individuals have more motor vehicle accidents. What do we know of the physiological and cognitive abilities of older drivers that could reduce their accident statistics? One other class of trip-makers that is of concern is teenage males. This group is far too accident prone and their numbers are often the major correlate of motor vehicle incidents. Could travel behavior research shed any light on the causes of this infortunate societal problem? What types of research questions should be asked of this younger driver?
Methods of analysis and planning The mathematical models and statistical methods that have been used and are being used in transportation planning are in part responsible for some of the transport problems we have currently. For example, it has long been argued that the gravity model will rarely predict a decrease in travel between any zonal pairs
North American transportation: W R Black
since most of the variables used to forecast input for the model are increasing in magnitude over time. There is a need to examine all of the models and methods used in transport planning to assess their merits, shortcomings, and bias. Spatial perspectives on project evaluation
One of the principal techniques used for decisionmaking at the federal level is benefit-cost analysis. This methodology catalogues the major benefits and costs of alternative projects and after incorporating certain discounting procedures yields a ratio that indicates if a project’s benefits exceeds its costs. The methodology has been the subject of numerous evaluations on its economic merits. Nevertheless, there is every reason to believe that the benefits and costs of a project should be equal if the system is in equilibrium, and in that case the only time they would be unequal is when the costs (and sometimes the benefits) are outside the spatial limits of the project area or the temporal limits of the project life. This methodology needs to be examined in more detail from these perspectives, as do some of the other project evaluation methodologies, e.g. cost-effectiveness analysis and life-cycle cost analysis. New approaches to modeling travel We have not seen any major changes in travel demand modeling for the last 25 years. The standard models in use seem to be able to capture major patterns of flow, but can we do better? Artificial neural network models have recently been shown to be more accurate than regression-based flow models and fully constrained gravity models, although an assessment of these methods on large samples is still needed (Black, 1995). Would it be worthwhile to evaluate other modeling approaches of the past (e.g. abstract mode models) using neural network methods?
17
would be teaching students how to drive and in the process exposing them to situations that are too risky in a real driving environment, e.g. crash avoidance. Obviously, the same ideas are transferable to truck drivers, airline pilots, and so forth. Beyond this it seems that virtual reality is seen by some as an alternative to traveling to meetings. Rather than a telephone connection, or a closed-circuit television connection, you could sit in the audience and interact with the other participants. This seems decades ahead given the current passive display technology, but it could move quickly. Certainly the analysis of this and similar alternatives to travel has merit. lkansition The above discussions of transport system, traffic flow attributes, trip-maker attributes, and modeling appear to be a collection of unconnected problems and methods, but to view it as such would be incorrect. The majority of the items discussed represent components of a global problem of sustainable transportation, or what the Europeans call ‘sustainable mobility’. Simply defined, ‘sustainable transportation is satisfying current transport and mobility needs without compromising the ability of future generations to meet these needs’ (Black, 1996). The following section examines why the current transport system is unsustainable and how the above research agenda fits within that global problem. Sustainable
transportation
Much planning and analysis work has been undertaken using a static framework. While this is acceptable in some cases we are now to the point where we can remotely monitor the traffic environment to assess real-time congestion, accidents, and speeds of vehicles. At the same time there does not appear to be any new methods that could incorporate these inputs. The advantages of such approaches should be evident; we could examine the operation of the network model in real time, identify problems as they occur, correct them, and gain greater insight into their causes.
Given the definition of sustainable transportation above, one might ask exactly why the current transport system is unsustainable. There are several reasons for this. The principal ones are (1) the limited nature of petroleum reserves, (2) the negative impacts of petroleum-based emissions on air quality, (3) the excessive number of fatalities and injuries due to motor vehicles, (4) traffic congestion, bordering on gridlock in many cities, and (5) urban sprawl. Of less importance, but certainly not insignificant, are problems related to noise pollution, structural damage due to vibration from motor vehicles, water pollution attributable to runoff from streets and highways, the loss of wetlands, open spaces, and historic facilities, ocean pollution due to oil spills and secondary impacts (Black, 1996). In general, these problems create costs, but they do not necessarily prevent future generations from meeting their transport needs. The following discussions focuses on the principal problems noted above. Discussions of the other factors may be found in inter alia MacKenzie et al. (1992) Miller and Moffet (1993), and Litman (1995).
Virtual reality
Petroleum s future
The emerging technology of virtual reality offers some novel applications in the field of transport; one of these
Petroleum is a finite natural resource. Although there are a variety of fuels derived from this source, e.g.
Dynamics of the problems: space-time modeling and visualization
18
North American transportation: W R Black
diesel fuel, propane gas, jet fuel, gasoline, and so forth, their petroleum origin raises serious questions of sustainability for such fuels. Estimates vary as to how much petroleum exists in the world. If the forecasts of 30 years ago were correct, the world would have run out of petroleum a decade ago. Obviously these reserves do not vary, but knowledge of their existence, location, and the technology for removing this resource change over time. Estimates for 1991 suggest that the world is using about 67 million barrels of petroleum each day, or 24 000 million (24 x 109) barrels a year. With total reserves estimated at about one trillion (1 x 1012) barrels, no additional discoveries of petroleum, and no increase in annual consumption, the world would run out of petroleum about the year 2032. If the fact that energy consumption is growing at an annual rate of 2.3% is factored in and applied to petroleum consumption, then reserves will be depleted by 2021. The finite nature of the petroleum-based fuels for our transportation vehicles makes them non-sustainable (Black, 1996). Even moderately larger discoveries of additional petroleum, viewed by many as unlikely, will probably not prolong the life of this fuel through the next century. The use of alternative fuels could extend the life of petroleum reserves, but their use is insignificant now. Their large-scale development, distribution and use will require substantial increases in the price of petroleumbased alternatives. Of course, this is exactly what economists argue will happen, i.e. as petroleum-based fuels become scarce their price will increase prolonging their use and allowing a market for the development of alternatives. Whether an extension of the life of petroleum fuels is desirable is questionable on other grounds.
the current vehicle fleet. These suggest the problem could be eliminated by 2020. Global warming, resulting in part from petroleumfueled motor-vehicle-based carbon emissions, will probably require action by some global set of nations, if action is to be taken at all. This atmospheric problem will be well underway before most policy-makers are willing to attack it. Although there is a tendency to take a doomsday perspective when global warming is discussed, it should be noted that the nature of the net impact of this phenomenon is currently unknown, and its potential social, economic, and transport impacts have not attracted much research interest. There are reasons to be somewhat optimistic about the problem of stratospheric ozone depletion in the long run. The Montreal Protocol, as amended, eliminated production of chlorofluorocarbons, the principal cause of ozone depletion, at the end of 1995. Unfortunately, ozone-depleting chlorine will remain in the stratosphere for some time and continue to damage the ozone layer. Recent estimates indicate that the hole in the Antarctic region in 1995 was the largest ever recorded. Nevertheless, the Montreal Protocol is a step in the right direction and it should bring this problem under control in time. Motor vehicle injuries and fatalities
Although motor vehicle fatalities and injuries are decreasing in some developed nations due to safety improvements, the global level of fatalities at one quarter million and injuries of ten million is clearly unacceptable. Significant reductions in these numbers could be achieved with further improvements in the safety of the world fleet; this could not occur without significant increases in vehicle prices. Nevertheless, we simply must continue to work on solutions to this problem.
Urban air quality and atmospheric changes
Prolonging the use of petroleum (or any fossil fuelbased alternative) will exacerbate local and global atmospheric problems. Among them are problems of acid deposition, global warming, metropolitan ozone, and urban air pollution. Another atmospheric problem, decreasing stratospheric ozone levels or holes in the air ozone layer, is due in part to automobile conditioners. There is every reason to believe that the problem of acid deposition will be eliminated over the next several years in the US as provisions of the 1990 Clean Air Act, which called for reductions in nitrous oxide and sulfur oxide emissions, become active. This will continue to be an international atmospheric problem until other countries implement similar legislation. Reductions in urban air pollution are quite possible and some would argue that elimination of this problem is only a function of cost and replacement over time of
Congestion
In some developing countries, highway congestion is due to a lack of adequate capacity. More developed countries have reached the point where increases in capacity simply lead to more use and eventually more congestion. This is clearly an unsustainable situation. Transport demand management techniques seem to offer the only reasonable alternative in developed countries, but some countries use tax and pricing mechanisms to discourage automobile ownership. Urban sprawl
Urban sprawl, although frequently viewed as a transport problem, is actually a land-use control problem. It is true that transport allows sprawl-type development to occur, but it does not mandate it. Proper land-use zoning and control could prevent sprawl and allow for
19
North American transportation: W R Black
the development urban uses.
of land in areas contiguous to existing
Table 2 Hughes personal travel
12-point
plan
for
sustainable
emissions
In summary, the major barriers to sustainable transport are limited petroleum reserves, the negative impacts of petroleum-based emissions on urban air quality and the global atmosphere, ozone depletion attributable in part to motor vehicle air-conditioning systems, excessive deaths and injuries due to motor vehicles, vehicle congestion on our streets and highways, and inefficient land-use development, due in part to transport.
1. Motor vehicles fuel economy labeling Fuel economy feebates or rebates Programs for the development of alternative fuels Speed limits for motor vehicles Employee travel schemes Environmental impact assessments for transport projects Increased spending on transit Redistribution of transport taxes to more energy efficient Accessibility taxes 10. Area licensing or road fees 11. Land-use planning 12. Carbon taxes to lessen motor vehicle use
Integrating sustainable
house Efict,
the transport transport
problems and
The transport problems identified previously may be restated as problems of infrastructure, safety, security, congestion, environmental impacts, fuel availability, trip and travel characteristics, full costing of transport, travel market saturation, communication alternatives, changing attitudes, and trip budgets. These all represent components of the sustainable transport problem as defined here or potential solutions to certain dimensions of that problem. The methods of analysis and planning represent changes that may help to better understand some of these problems. It is clear that most existing methods have not prevented the sustainability problem from becoming worse over the years, and we need to try new methodological approaches if we are going to begin to solve this problem. It is in the area of research on this broad area of sustainable transport that North America and Europe can mutually benefit from cooperative research efforts. For example, a recent plan that would yield sustainable levels of emissions from personal travel includes twelve steps to follow (see Table 2). Most of these actions have been undertaken in North America for one reason or another, and an existing body of research has been compiled on their results. At the same time European members of the Organization for Economic Co-operation and Development (OECD) as well as members of the European Community Ministers of Transport (ECMT) have taken a much harder look at what actions must be taken if the world is to move toward sustainability in the transport sector. Cooperative research on this problem will be mutually beneficial to all participants.
from
2. 3. 4. 5. 6. 7. 8. 9.
Source: After Peter Hughes (1993), Personal Transpoti and the GreenEarthscan Publications, London.
Acknowledgements The author is grateful for the comments of David L Greene, Kingsley E Haynes, David C Hodges, and Donald G Janelle on an earlier version of this paper. References Black, W. R. (1995) Spatial interaction modeling using artificial neural networks. Journal of Tmnsport Geography 3, 159-166. Black, W. R. (1996) Sustainable transportation: a US perspective. Journal of Transport Geography 4, 151-159.
Garrison, W. L. (1985) Basic research on transportation facilities. Transportation Research 19A, 5 11-518. Litman, T. (1995) Transmmation Cost Analvsis. Victoria Transport Policy Inst‘itute,‘Vanco~ver. MacKenzie. J. J. (1994) The I&W to the Car: Electric and Hvdroaen Vehicles ‘in th‘e 2isf Ceniury. World Resources IAstit;te, Washington, DC. MacKenzie, J. J., Dower, R. and Chen. D. T. (1992) The Going Rate. ’ World Resources Institute, Washingion, DC: Miller. P. and Moffet. J. (1993) The Price of Mob&v: Uncoverinn the H&en Costs of Trbns&tati&. Natural ‘Resource Defense Fund, Washington, DC. Nadis, S. and MacKenzie, J. J. (1993) Car Trouble. Beacon Press, Boston. Ogden, J. M. and DeLuchi, M. A. (1993) Solar hydrogen transportation fuels. In Transportation and Global Climate Change, ed. D. L. Greene and D. J. Santini, pp. 189-241. American Council for an Energy Efficient Economy, Washington, DC. Sperling, D. (1995) Future Drive: Electric Vehicles and Sustainable Transportation. Island Press, Washington, DC. Transportation Research Board (1994) Curbing Gridlock: Peak-Period Fees to Relieve Trufiic Congestion, Special Report 242. National Academy Press, Washington, DC. Transportation Research Board (1995) Expanding Metropolitan Highways: Implications for Air Quality and Energy Use, Special Report 245. National Academy Press, Washington, DC.
PII:SO966.6923(96)00042-7
ofTmnspon Geogmphy Vol.
5. No. I, pp. 12-19. 1997 0 1997 Ekvier Science Lid All rights reserved. Printed in Great Britain 0966-6923197 $17.00+0.00
North American transportation: perspectives on research needs and sustainable transportation William R Black Department of Geography, Indiana University, Bloomington, IN 47405, USA
5% of Mexico’s area. From these perspectives Mexico is underdeveloped in a transport context. The North American Free Trade Agreement (NAFTA) has created the potential for significant changes in the US, Canada, and Mexico, and the interaction between these countries. For example, prior to the agreement Mexican trucks could not operate in the US (except in commercial zones of border cities) and US truckers could not operate in Mexico. As of December 18, 1995, truckers of each country will be allowed to obtain permits to operate in the other country for international cargo transport. Also included in NAFTA are provisions liberalizing the ownership of carriers in the participating countries. Rail transport is hardly touched by the agreement, and gauge differences in Mexico make transport interaction between it and the US and Canada im~ssible, although the latter two countries interchanged traffic even prior to the agreement. There have been numerous pieces of legislation enacted and executive orders signed that have attempted to improve different aspects of the transport system of the US and Canada. Among these the following would have to be recognized: the US National Environmental Policy Act of 1969 and its requirements for environmental impact assessments of federal transport projects; the US Clean Air Act of 1970 and its amendments, which have set limits on motor vehicle emissions and established CAFE (corporate average fuel efficiency) standards; and the US Intermodal Surface Transportation Efficiency Act (ISTEA) and its requirements for public transit, congestion, safety, intermodal and pavement managearea ment systems, and state and metropoIitan planning. As noted previously, Canada has also enacted legislation to improve air quality, vehicular emissions, and fuel efficiency standards. Mexico has been less active in this general area. In spite of the legislative activity, executive actions, and international agreements, there continues to be transportation problems in the US, Canada, and Mexico, and those problems are becoming larger and
The transportation system in North America is one of the most advanced in the world. For the most part it facilitates the movement of goods and people in a reliable, efficient and convenient manner. The quality of the highways, the rail systems, and the airline networks is of a high caliber. At the same time these networks are less dense in Canada and of a lower quality in Mexico, as compared to the US. The US has passed legislation over the past four decades to build a national interstate highway network, to decrease and then increase speed limits on the nation’s interstate highways, to subsidize public transit operations, and capital expenditures, to create a research, for-profit national rail passenger system, and to deregulate (1) railroad operations devoted to the movement of freight (Regional Rail Reorganization Act of 1973, Rail Revitalization and Regulatory Reform Act of 1976, and the Staggers Rail Act of 1980), (2) domestic intercity airline passenger systems (Airline Deregulation Act of 1978) (3) intercity bus operations, and (4) motor carriers (Motor Carrier Deregulation Act of 1982). Similarly, Canada has enacted legislation to deregulate much of its transport sector and to privatize public systems (Canadian National Railroad, Air Canada, and VIA Rail). On the environmental front there is a Clean Air Act and a Motor Vehicle Safety Act (with provisions to control emissions). Provincial agencies responsible for energy and the environment are currently trying to set higher motor vehicle fuel efficiency standards. There has been less transport legislation activity in Mexico. The country has a national railroad (Ferrocarriles Nacionales de Mexico), but there is little discussion about privatizing the system. There are about 6.5 million automobiles and 5 million motor carriers. These numbers are comparable to the motor vehicle fleet in Texas, a state with a population equal to about 20% of that found in Mexico. The highway network consists of 242 000 kilometers, but only about 49 000 kilometres are classified as main roads; this is comparable to the state of Kansas, with an area about 13
North American transportation: W R Black
more complex. In general the problems spread across the major areas of transport system attributes (intermodal transfers, infrastructure decline, congestion, security, safety, environmental impacts, and long-term fuel availability), traffic flow attributes (including trip characteristics, full costing of travel, travel market saturation, substitution of communication technology for travel), trip-maker attributes (including driver choice behavior and attitudinal change studies), and methods of analysis and planning (including project assessment techniques, new travel modes and analytical methods, including spatial-temporal analysis methods, neural networks, three-dimensional visualization, and virtual reality). The pages that follow present more detail on the transport problems identified and suggest some promising methodologies worthy of further analysis. This is followed by an attempt to synthesize and characterize the transport future envisioned for the first quarter of the next century. That future will resemble what currently exists, with the exception of a greater role for technology and a greater concern for the environment. It is seen within the context of a ‘sustainable transport future’, and the research activities identified here are directed toward assuring that future. Tkansport systems Intermodalism
NAFTA has moved toward significantly improving the movement of goods between the countries of North America. At the same time the most active growth area for the transport of goods is in the area of containers. The movement of these from ships to road to rail and perhaps back to trucks is still not as seamless as it could be. The use of scanning techniques for customs inspections is already in place, but what additional improvements could be made to improve the efficiency of these flows? Numerous geographic databases have been developed that depict the various transport networks of North America (e.g. rail, highway, and waterway). Most intermodal analyses require the use of a single intermodal network with comparable shipping costs, time spent in transit, transfer costs, and field definitions. Such a network needs to be created to examine intermodal flow alternatives and methods of working with intermodal or multimodal flows. Infrastructure
Without a doubt one of the major transport problems of today is maintaining and developing new infrastructure. Most of the first-generation rail transit systems in the US will require major investments in the next one or two decades. Highways and bridges are unable to endure the stress placed upon them by the heavier
13
trucks of the last two decades. Port facilities will have difficulty handling the new 5000 twenty-foot-equivalent container vessels. Investing in all of these facilities will require the development of new funding mechanisms and revenue sources. At the same time one is reminded of the statement by Garrison (1985) that ‘most frequently, the infrastructure problem is described as not enough money, and its solution is more money’. He goes on to suggest the need for more basic research on infrastructure systems, existing and new. This need has yet to be addressed. A related question is whether we should be considering a freight rail line to connect Canada with Mexico? The only connections being discussed today are highway connections. Given the length of this connection, a rail line connection is feasible.
safety In 1994 the highway transport system of the US _. claimed the lives of 40 676 motor vehicle users and pedestrians. This statistic is appalling in its magnitude, but the situation has actually improved over the last couple of decades. This is due in part to the required use of seat belts and other safety-related improvements, as well as more severe treatment of intoxicated drivers. Nevertheless, there is a need for further research to discern other causal factors and possible real-time systems that would alert users and safety officials of a developing problem. Security Transit systems in some urban areas are avoided because of the potential risk of criminal activity on those systems during evening hours. There is a need for research that would assess to what extent this is a real problem and to what extent it is a question of perception. To the extent that the problem is real, what feasible approaches exist to halt such activity? It should be apparent that transport modes may well become targets for acts of terrorism from those within or outside of North America. The air passenger system has had a long history of problems in this area. Can the railroad passenger and freight system transfer any of air transport’s approaches to their systems? Congestion
A problem of growing concern in North America is the increase in highway congestion that has occurred in the last decade (Transportation Research Board, 1994). In general, it is fairly certain that additions to capacity are not the answer to this problem (Transportation Research Board, 1995). That has been the approach during the second half of this century and it has simply resulted in more congested highways. We need to make sure that we are measuring the problem in an acceptable manner and then we must proceed to
14
North American transportation: W R Black
identify the contribution of different activities (traffic calming devices, staggered work hours, and so forth) in reducing congestion. It has been suggested that the US is approaching a saturation point with regard to male drivers using the system. Where does the female population stand in this regard? Will they become the primary reason for additions to congestion in the coming decades? Can anything be done to prevent this growth in congestion? Another congestion problem has become evident at several of North America’s airports, while other airports have excess capacity. This imbalance is attributable in part to the practice of hubbing, which results in significant traffic arriving and departing from hub facilities while non-hub airports have significantly Are there network optimization less activity. approaches that could evaluate the costs of using multiple hubs and their impact on congestion levels at different airports? While the merits of hubbing for the airline are obvious, it would appear that each airline passenger passing through a hub loses two hours of their time in comparison to those that use direct flights. This generates significant social and productivity costs. Environmental impacts Perhaps no single area is impacted more by transport than the environment. Every sector of the natural environment (water, vegetation, geomorphology, soils, animal life, and the atmosphere) receives negative impacts from various transport systems. In some cases there is little knowledge about the scope of these impacts, e.g. the impacts of transport on the movement or fatalities of animal populations. However, it should be apparent that the atmosphere is currently receiving the major negative externalities at this time. There are four major problem areas: urban air quality, ozone depletion, acid precipitation, and global warming. Researchers have been working with the development of models to evaluate transport impact on urban air quality for nearly a quarter of a century. A fundamental problem in this area is the lack of enough monitoring devices to measure the actual pollution occurring from the transport sector at a given point in time. A major air quality database for an urban area would facilitate model development in this area. The use of CFCs (chlorofluorocarbons) in automobile air conditioners have been a major contributor to the ozone depletion problem. Provisions of the Montreal Protocol as amended that brought a halt to the production of CFCs at the end of 1995 should help to reduce the magnitude of this problem. However, the alternative coolants developed to replace CFCs also bring along certain problems for the atmosphere. There are already some indications that this problem will be of less significance in twenty years, but what more can be done in the interim?
Acid deposition exists in most parts of the US, Canada, and Mexico, but it is a problem only in selected areas due to the low buffering ability of the soils there. Motor vehicles contribute to this problem through emissions of sulfur and nitrogen oxides. While the impacts of the resultant sulfuric and nitric acids are known in parts of the northeastern US and southeastern Canada, there has been little research into the potential impacts elsewhere, e.g. on structures or on surfaces that can rust or corrode. It is also not immediately apparent what the ‘atmospheric transport process’ is that takes motor vehicle emissions to the upper troposphere. The overwhelming scientific consensus is that the planet will undergo a warming attributable to emissions of what are called greenhouse gases, e.g. carbon dioxide, methane, CFCs, and nitrogen oxides, among others. The only questions of any merit today are exactly how much warming will occur and what will be the scope of its impacts on social and economic systems. Motor vehicles are a primary contributor of most of the recognized greenhouse gases. The major greenhouse gas is carbon dioxide; motor vehicles are responsible for nearly two trillion pounds of carbon each year in the US. How can we combat this problem, or have we already accepted its likelihood? Even if we completely halt the emissions of greenhouse gases, carbon would remain in the atmosphere for more than 100 years and any observed warming would continue for that length of time as well. What types of carbon emission trading systems might be worth examining for the transport sector? Fuel availability Many of the proposals for slowing down the global warming that is anticipated involve the use of alternative fuels (Nadis and MacKenzie, 1993; Ogden and DeLuchi, 1993; MacKenzie, 1994; Sperling, 1995). Several of these ‘new fuels’ are tied to petroleum, e.g. gasohol which may be 90% gasoline, oxygenated gasolines, and so forth. We seem to be ignoring the finite nature of petroleum-based fuels. Recent forecasts of known and expected petroleum reserves suggest that the world will run out of petroleum midway through the 21st century. It makes sense to begin looking at alternative fuels and systems and researching the feasibility of their large-scale development, adoption, and distribution. Accessibility impacts Congestion in some North American central cities has led to accessibility advantages on the edges of cities. What are the social and economic implications of these ‘edge cities’? Will this lead to a second major phase of suburbanization in the US and Canada? Beyond urban areas there are areas of the Canadian provinces and parts of Mexico that are inaccessible to
North American transportation: W R Black
the major transport lines nearest them. How can these often geographically remote areas be ‘connected’ to the rest of the system in a cost-effective manner?
15
proposals would be, and what mechanisms are needed to distribute the revenues generated. Travel market saturation
System valuation
Assessments of the value of transport systems often note the employment in that sector. If communication proves to be an acceptable substitute for transportation will this lessen the value of transport as a whole? If project improvements must demonstrate benefits for users (and benefits for non-users now in the UK), isn’t further expansion or rehabilitation of the highway systems in some parts of North America unlikely? If communication is an alternative for the journey to work, can the time savings for the latter trip be used to justify a highway investment? These topics certainly merit analysis. ‘Ikaffic flow attributes Improving the transport systems of North America will not solve all of its transport problems. For example, it is now recognized that the construction of additional highways or even the addition of capacity to existing highways will not eliminate highway congestion problems in the US. To do this there must begin to be some fundamental changes in the nature of tripmaking and travel behavior. This section examines some areas where change is both likely and necessary.
As noted above, it has been argued that aggregate congestion will not become much worse in the US because the male market for motor vehicles has nearly been saturated, i.e. additional cars would simply increase the ratio of cars to male drivers which is currently near unity. Research has tended to support these ideas. The inference is that if there is additional motor vehicle travel, and therefore congestion, it will
Table 1 ‘Ikansportation
costs
Accident costs Deductibles Productivity losses Value of life
Operating costs Fuel, oil Registration Licenses
Capital costs Highways, streets, runways, tracks Planning Land acquisition Preliminary engineering Construction Deferred investment Terminals and garages Vehicles (motor vehicles, aircraft, buses, etc.)
Parking-related costs Fees Fines Governmental (subsidized) Private residential
Congestion (see Time costs, Operating costs, and Pollution Fares
There is a great deal that we do not know about urban travel and trip-making behavior. Research has posited the existence of a frictionless zone for urban travel, but we know little more about this today than we did a quarter century ago. We have seen a growing recognition of trip-chaining, which is thought to better represent travel patterns. However, whether trips are chained or treated as individual trips from origins to destinations has no impact on their analysis. The notions of travel budgets and minimum travel requirements are also worth analyzing in more detail.
Highway-related governmental Services Police Fire Criminal justice
Several recent studies have made it very clear that the US, Canada, and, to a lesser extent, Mexico are indirectly subsidizing the cost of motor vehicle travel by allowing many of the costs generated by this mode to be covered by non-transport sectors (see Table I) (MacKenzie et al., 1992; Miller and Moffet, 1993; Litman, 1995). If these costs were included in the price of fuel, it would significantly decrease the demand for travel, decrease congestion, and provide funds for many of the external costs generated by this transport sector. There is a need to examine which costs should realistically be included, what the impacts of such
co;
co
Trip characteristics
Full costing of travel
Pollution Air Air quality NO.
Land-related costs Archaeological sites Historic buildings Loss of open space Loss of wetlands Urban sprawl
SPM SO, Urban ozone Acid deposition Stratospheric ozone depletion Climate change Long-term health Noise Structural Vibration damage Water Marine (spills) Runoff Property values
Loss and damage
Repair and maintenance Vehicles Facilities
Macroeconomic costs Balance of trade payments Inflation
Subsidies
Maintenance costs Grass cutting Snow removal Patching
Time costs Commercial Personal Transportation
equity
Manufacturing or refining Energy costs Resource use Military security for petroleum Source: William R. Black, Dean L. Munn, Richard J. Black and Jirong Xie (1995), Modal Choices: An Approach to Comparing the Costs of Transportation Alternatives, Transportation Research Center, Indiana University, Bloomington.
16
North American transportation: W R Black
be attributable to more women driving. However, there are also questions of where and when vehicles are used by men and women. Is this the real congestion problem? These ideas need to be examined in some detail.
actual changing of attitudes appears to be due more to marketing as opposed to education. In the historical highway tax case above, were chambers of commerce and highway construction interests behind the broad acceptance of that tax? Isn’t marketing simply a more aggressive form of education?
Substitution of communication It has long been argued that high-quali~ communications can result in the substitution of communication for travel. This may have happened on several occasions in the recent past, but the current emphasis on telecommuting or teleworking has begun to enliven this potential substitution effect. While estimates vary on the magnitude of this substitution effect, it may be substantial. We need better methods of estimating the potential scope of teleworking. Research is necessary to determine the types of employment that can make use of this communication option and the magnitude of the daily reduction in travel. Changes in information technology have already had a significant impact on commodity flows, warehousing, and industries’ over-reliance on the transport system, as best illustrated by ‘just-in-time’ delivery systems. This leads to inefficiencies in flow volumes and risks of flow inter~ptions. It is recognized that congestion in traffic flows is in part attributable to urban sprawl and low-density housing. It is disturbing to consider the footloose capabilities for housing ‘if communication links substitute for transport links. While there may very well be a decrease in the length of daily trip-making, the oncea-week trip to the office (often suggested as necessary for telecommuters) may consume more fuel than five daily trips. Research has shown that the length of time devoted to the journey to work has not changed much in recent years, but has tended to remain the same. Would one day trip have a length equal to the time of the previous five daily trips?
‘II-ip-maker attributes Changing attitudes There is a necessity for people’s attitudes toward transport solutions to change if we are to solve several transport problems. For example, the external cost of using motor vehicles is significant and generates costs that are not covered currently by motor vehicle taxes. At the same time there is a belief on the part of policymakers that any tax increase is unacceptable. This effectively rules out these types of policy solutions. We are reminded of the fact that all 48 states of the US enacted highway fuel taxes between 1919 and 1927. Historical research on the process of adopting these taxes might be very informative and assist us in understanding the process of adopting such measures. It may be argued that adoption of necessary changes takes place because of educational efforts, but the
Eip budgets Trip budgets are gaining more and more recognition as an influential determinant of travel behavior. It is also said that Americans drive too much, suggesting there is some optimal (minimal) level of travel. Would it be possible to develop a ‘minimum requirements approach’ to travel budgets so that we can at least talk about the levels of travel reduction that are possible? Should travel behavior be examined in the context of a total activity budget? If shifts are made to a four-day work-week, what would be the impact on travel? Family structure and travel demand There have been significant changes in the structure of the North American family, primarily in Canada and the US. There are increases in divorce, single parent households, and individuals living alone. The net result of these changes from a transport perspective is an increase in the number of trip-making units. What once could be accomplished by one trip-maker for a family, may now require two or three individuals. What other travel changes have resulted from these social trends? Age and trip-making There are two cohort groups of the population that are of concern with regard to motor vehicle safety. The first of these is the ageing driver. Estimates suggest that one out of five motor vehicle drivers in North America will be over the age of 65 in 2010. It is also known that, after age 55, individuals have more motor vehicle accidents. What do we know of the physiological and cognitive abilities of older drivers that could reduce their accident statistics? One other class of trip-makers that is of concern is teenage males. This group is far too accident prone and their numbers are often the major correlate of motor vehicle incidents. Could travel behavior research shed any light on the causes of this infortunate societal problem? What types of research questions should be asked of this younger driver?
Methods of analysis and planning The mathematical models and statistical methods that have been used and are being used in transportation planning are in part responsible for some of the transport problems we have currently. For example, it has long been argued that the gravity model will rarely predict a decrease in travel between any zonal pairs
North American transportation: W R Black
since most of the variables used to forecast input for the model are increasing in magnitude over time. There is a need to examine all of the models and methods used in transport planning to assess their merits, shortcomings, and bias. Spatial perspectives on project evaluation
One of the principal techniques used for decisionmaking at the federal level is benefit-cost analysis. This methodology catalogues the major benefits and costs of alternative projects and after incorporating certain discounting procedures yields a ratio that indicates if a project’s benefits exceeds its costs. The methodology has been the subject of numerous evaluations on its economic merits. Nevertheless, there is every reason to believe that the benefits and costs of a project should be equal if the system is in equilibrium, and in that case the only time they would be unequal is when the costs (and sometimes the benefits) are outside the spatial limits of the project area or the temporal limits of the project life. This methodology needs to be examined in more detail from these perspectives, as do some of the other project evaluation methodologies, e.g. cost-effectiveness analysis and life-cycle cost analysis. New approaches to modeling travel We have not seen any major changes in travel demand modeling for the last 25 years. The standard models in use seem to be able to capture major patterns of flow, but can we do better? Artificial neural network models have recently been shown to be more accurate than regression-based flow models and fully constrained gravity models, although an assessment of these methods on large samples is still needed (Black, 1995). Would it be worthwhile to evaluate other modeling approaches of the past (e.g. abstract mode models) using neural network methods?
17
would be teaching students how to drive and in the process exposing them to situations that are too risky in a real driving environment, e.g. crash avoidance. Obviously, the same ideas are transferable to truck drivers, airline pilots, and so forth. Beyond this it seems that virtual reality is seen by some as an alternative to traveling to meetings. Rather than a telephone connection, or a closed-circuit television connection, you could sit in the audience and interact with the other participants. This seems decades ahead given the current passive display technology, but it could move quickly. Certainly the analysis of this and similar alternatives to travel has merit. lkansition The above discussions of transport system, traffic flow attributes, trip-maker attributes, and modeling appear to be a collection of unconnected problems and methods, but to view it as such would be incorrect. The majority of the items discussed represent components of a global problem of sustainable transportation, or what the Europeans call ‘sustainable mobility’. Simply defined, ‘sustainable transportation is satisfying current transport and mobility needs without compromising the ability of future generations to meet these needs’ (Black, 1996). The following section examines why the current transport system is unsustainable and how the above research agenda fits within that global problem. Sustainable
transportation
Much planning and analysis work has been undertaken using a static framework. While this is acceptable in some cases we are now to the point where we can remotely monitor the traffic environment to assess real-time congestion, accidents, and speeds of vehicles. At the same time there does not appear to be any new methods that could incorporate these inputs. The advantages of such approaches should be evident; we could examine the operation of the network model in real time, identify problems as they occur, correct them, and gain greater insight into their causes.
Given the definition of sustainable transportation above, one might ask exactly why the current transport system is unsustainable. There are several reasons for this. The principal ones are (1) the limited nature of petroleum reserves, (2) the negative impacts of petroleum-based emissions on air quality, (3) the excessive number of fatalities and injuries due to motor vehicles, (4) traffic congestion, bordering on gridlock in many cities, and (5) urban sprawl. Of less importance, but certainly not insignificant, are problems related to noise pollution, structural damage due to vibration from motor vehicles, water pollution attributable to runoff from streets and highways, the loss of wetlands, open spaces, and historic facilities, ocean pollution due to oil spills and secondary impacts (Black, 1996). In general, these problems create costs, but they do not necessarily prevent future generations from meeting their transport needs. The following discussions focuses on the principal problems noted above. Discussions of the other factors may be found in inter alia MacKenzie et al. (1992) Miller and Moffet (1993), and Litman (1995).
Virtual reality
Petroleum s future
The emerging technology of virtual reality offers some novel applications in the field of transport; one of these
Petroleum is a finite natural resource. Although there are a variety of fuels derived from this source, e.g.
Dynamics of the problems: space-time modeling and visualization
18
North American transportation: W R Black
diesel fuel, propane gas, jet fuel, gasoline, and so forth, their petroleum origin raises serious questions of sustainability for such fuels. Estimates vary as to how much petroleum exists in the world. If the forecasts of 30 years ago were correct, the world would have run out of petroleum a decade ago. Obviously these reserves do not vary, but knowledge of their existence, location, and the technology for removing this resource change over time. Estimates for 1991 suggest that the world is using about 67 million barrels of petroleum each day, or 24 000 million (24 x 109) barrels a year. With total reserves estimated at about one trillion (1 x 1012) barrels, no additional discoveries of petroleum, and no increase in annual consumption, the world would run out of petroleum about the year 2032. If the fact that energy consumption is growing at an annual rate of 2.3% is factored in and applied to petroleum consumption, then reserves will be depleted by 2021. The finite nature of the petroleum-based fuels for our transportation vehicles makes them non-sustainable (Black, 1996). Even moderately larger discoveries of additional petroleum, viewed by many as unlikely, will probably not prolong the life of this fuel through the next century. The use of alternative fuels could extend the life of petroleum reserves, but their use is insignificant now. Their large-scale development, distribution and use will require substantial increases in the price of petroleumbased alternatives. Of course, this is exactly what economists argue will happen, i.e. as petroleum-based fuels become scarce their price will increase prolonging their use and allowing a market for the development of alternatives. Whether an extension of the life of petroleum fuels is desirable is questionable on other grounds.
the current vehicle fleet. These suggest the problem could be eliminated by 2020. Global warming, resulting in part from petroleumfueled motor-vehicle-based carbon emissions, will probably require action by some global set of nations, if action is to be taken at all. This atmospheric problem will be well underway before most policy-makers are willing to attack it. Although there is a tendency to take a doomsday perspective when global warming is discussed, it should be noted that the nature of the net impact of this phenomenon is currently unknown, and its potential social, economic, and transport impacts have not attracted much research interest. There are reasons to be somewhat optimistic about the problem of stratospheric ozone depletion in the long run. The Montreal Protocol, as amended, eliminated production of chlorofluorocarbons, the principal cause of ozone depletion, at the end of 1995. Unfortunately, ozone-depleting chlorine will remain in the stratosphere for some time and continue to damage the ozone layer. Recent estimates indicate that the hole in the Antarctic region in 1995 was the largest ever recorded. Nevertheless, the Montreal Protocol is a step in the right direction and it should bring this problem under control in time. Motor vehicle injuries and fatalities
Although motor vehicle fatalities and injuries are decreasing in some developed nations due to safety improvements, the global level of fatalities at one quarter million and injuries of ten million is clearly unacceptable. Significant reductions in these numbers could be achieved with further improvements in the safety of the world fleet; this could not occur without significant increases in vehicle prices. Nevertheless, we simply must continue to work on solutions to this problem.
Urban air quality and atmospheric changes
Prolonging the use of petroleum (or any fossil fuelbased alternative) will exacerbate local and global atmospheric problems. Among them are problems of acid deposition, global warming, metropolitan ozone, and urban air pollution. Another atmospheric problem, decreasing stratospheric ozone levels or holes in the air ozone layer, is due in part to automobile conditioners. There is every reason to believe that the problem of acid deposition will be eliminated over the next several years in the US as provisions of the 1990 Clean Air Act, which called for reductions in nitrous oxide and sulfur oxide emissions, become active. This will continue to be an international atmospheric problem until other countries implement similar legislation. Reductions in urban air pollution are quite possible and some would argue that elimination of this problem is only a function of cost and replacement over time of
Congestion
In some developing countries, highway congestion is due to a lack of adequate capacity. More developed countries have reached the point where increases in capacity simply lead to more use and eventually more congestion. This is clearly an unsustainable situation. Transport demand management techniques seem to offer the only reasonable alternative in developed countries, but some countries use tax and pricing mechanisms to discourage automobile ownership. Urban sprawl
Urban sprawl, although frequently viewed as a transport problem, is actually a land-use control problem. It is true that transport allows sprawl-type development to occur, but it does not mandate it. Proper land-use zoning and control could prevent sprawl and allow for
19
North American transportation: W R Black
the development urban uses.
of land in areas contiguous to existing
Table 2 Hughes personal travel
12-point
plan
for
sustainable
emissions
In summary, the major barriers to sustainable transport are limited petroleum reserves, the negative impacts of petroleum-based emissions on urban air quality and the global atmosphere, ozone depletion attributable in part to motor vehicle air-conditioning systems, excessive deaths and injuries due to motor vehicles, vehicle congestion on our streets and highways, and inefficient land-use development, due in part to transport.
1. Motor vehicles fuel economy labeling Fuel economy feebates or rebates Programs for the development of alternative fuels Speed limits for motor vehicles Employee travel schemes Environmental impact assessments for transport projects Increased spending on transit Redistribution of transport taxes to more energy efficient Accessibility taxes 10. Area licensing or road fees 11. Land-use planning 12. Carbon taxes to lessen motor vehicle use
Integrating sustainable
house Efict,
the transport transport
problems and
The transport problems identified previously may be restated as problems of infrastructure, safety, security, congestion, environmental impacts, fuel availability, trip and travel characteristics, full costing of transport, travel market saturation, communication alternatives, changing attitudes, and trip budgets. These all represent components of the sustainable transport problem as defined here or potential solutions to certain dimensions of that problem. The methods of analysis and planning represent changes that may help to better understand some of these problems. It is clear that most existing methods have not prevented the sustainability problem from becoming worse over the years, and we need to try new methodological approaches if we are going to begin to solve this problem. It is in the area of research on this broad area of sustainable transport that North America and Europe can mutually benefit from cooperative research efforts. For example, a recent plan that would yield sustainable levels of emissions from personal travel includes twelve steps to follow (see Table 2). Most of these actions have been undertaken in North America for one reason or another, and an existing body of research has been compiled on their results. At the same time European members of the Organization for Economic Co-operation and Development (OECD) as well as members of the European Community Ministers of Transport (ECMT) have taken a much harder look at what actions must be taken if the world is to move toward sustainability in the transport sector. Cooperative research on this problem will be mutually beneficial to all participants.
from
2. 3. 4. 5. 6. 7. 8. 9.
Source: After Peter Hughes (1993), Personal Transpoti and the GreenEarthscan Publications, London.
Acknowledgements The author is grateful for the comments of David L Greene, Kingsley E Haynes, David C Hodges, and Donald G Janelle on an earlier version of this paper. References Black, W. R. (1995) Spatial interaction modeling using artificial neural networks. Journal of Tmnsport Geography 3, 159-166. Black, W. R. (1996) Sustainable transportation: a US perspective. Journal of Transport Geography 4, 151-159.
Garrison, W. L. (1985) Basic research on transportation facilities. Transportation Research 19A, 5 11-518. Litman, T. (1995) Transmmation Cost Analvsis. Victoria Transport Policy Inst‘itute,‘Vanco~ver. MacKenzie. J. J. (1994) The I&W to the Car: Electric and Hvdroaen Vehicles ‘in th‘e 2isf Ceniury. World Resources IAstit;te, Washington, DC. MacKenzie, J. J., Dower, R. and Chen. D. T. (1992) The Going Rate. ’ World Resources Institute, Washingion, DC: Miller. P. and Moffet. J. (1993) The Price of Mob&v: Uncoverinn the H&en Costs of Trbns&tati&. Natural ‘Resource Defense Fund, Washington, DC. Nadis, S. and MacKenzie, J. J. (1993) Car Trouble. Beacon Press, Boston. Ogden, J. M. and DeLuchi, M. A. (1993) Solar hydrogen transportation fuels. In Transportation and Global Climate Change, ed. D. L. Greene and D. J. Santini, pp. 189-241. American Council for an Energy Efficient Economy, Washington, DC. Sperling, D. (1995) Future Drive: Electric Vehicles and Sustainable Transportation. Island Press, Washington, DC. Transportation Research Board (1994) Curbing Gridlock: Peak-Period Fees to Relieve Trufiic Congestion, Special Report 242. National Academy Press, Washington, DC. Transportation Research Board (1995) Expanding Metropolitan Highways: Implications for Air Quality and Energy Use, Special Report 245. National Academy Press, Washington, DC.