Feature

Railways and The Environment (part 2)

Effects of High-Speed Transportation Systems
on Environmental Improvement in Japan

In Japan, the use of motor vehicles stillshows no signs of decreasing and roadtraffic continues to rise in terms of bothurban and inter-city transport. As a result, a reduction in carbon dioxide (CO2)emissions by the transport sector is far
from being achieved. Similarly, local air
pollution caused by nitrogen oxides (NOx)and suspended particulate matter (SPM)
is still common and many urban areas failto meet government air quality standards.
Meanwhile, public pressure for environmental improvement has intensified inrecent years. The Japanese government
agreed to reduce emissions of gases causing global warming at the UN Convention on Climate Change (COP3) held in
Kyoto in December 1997. In July andAugust 1998, suits were filed against the
government and highway authorities in
Osaka and Kawasaki, respectively, alleging their liability for local air pollution
caused by exhaust gases. Clearly, drastic
and urgent actions are expected from thetransport sector toward environmental
improvement, especially in the management of urban and inter-city transport.
This article reviews major environmental
issues facing Japan and analyzes the current status of environmental improvement
policies undertaken by the Ministry ofTransport (MOT), along with technology
to control pollution at source. In particular, evaluation of various environmental
parameters is becoming important, especially analytical systems to quantify theeffects of policies and programmes. Major issues related to such quantitative assessment are identified and analyzed.
Finally, we describe a recently developed
analytical framework to evaluate the effects of environmental improvement measures on inter-city transport, including
upgrading of rail service levels, increasing charges for using automobiles, andpromoting low-pollution vehicles. The
evaluation results for various programmes
are presented.

12Haruo Ishida and Seiji Iwakura
Global Warmingand Local Air Pollution
Figure 1 shows the breakdown of CO2
emissions by country in 1992. Japan ranks
fourth in absolute amount of CO2 emissions. Per capita emissions are around
50% of the USA and Canada, at the samelevel as the UK and Italy, and four times
the level of China. The ratio of emissions
to GNP is equivalent to that of Italy, 50%
that of the USA, Canada, and the UK, and
5% that of China. By industry, the transport sector accounts for 18.9% of the total CO2 emissions in Japan, and is the key
to effective reduction of emissions. Within
the transport sector, passenger transport
produces the dominant (64.4%) share ofemissions, of which automobile transport
accounts for 87.5%. The share of emissions by the transport sector has been ris-

ing each year, explaining why CO2 emissions by the transport sector grew 90%
between 1973 and 1994, in contrast to
the 20% increase by all sectors. Table 1
shows the environmental impacts predicted by the Environment Agency on Japan caused by doubling the present CO2
concentration; the impacts are extensive.
Table 2 summarizes the impacts of local
air pollutants on people. The NOx levelhas been gradually declining, but it is still
higher in major urban areas than exhaustemission standards. In 1991, the carbon
monoxide (CO) levels at all air quality
monitoring stations throughout Japan met
the emission standards. The level of sulphur oxides (SOx) declined by 82.4%
between 1970 and 1989, due to reduction of the sulphur content of fuels, wider
use of desulphurization technology, andimproved fuel efficiency. Progress with

Figure 1 National CO2 Emissions in 1992

USA
21.9%

Others44.5%

World Total
Approx.
6,100 million
tonne-C

India Germany Japan
3.4% 3.9% 4.9%

Russia9.4%

Private sector(businesses)
11.2%

Industrial sector
39.3%

Japan Total
Approx.
330 million
tonne-C

Private sector(households)
12.4%
Transport sector
18.9%
Ships
Aircraft 3.9%
4.0%
Railways
4.7%
Buses & taxis
6.7%

Cargo
35.6%

Japan Railway & Transport Review 18 • December 1998

China
11.9%

Waste Others
3.9% 2.8%
Industrial process
4.6%
Energy conversion
sector7.0%

JapanTransport
SectorPrivate trucks
18.8%
Passengers
64.4%

Japan
Passenger
SectorPrivatepassenger cars
62.0%

Copyright © 1998 EJRCF. All rights reserved.

Table 1
SPMs is rather slow; in 1991, only 50%
of air quality monitoring stations and just
30% of exhaust gas monitoring stations
met the environmental standards. Diesel
vehicles are estimated to produce 20% to
40% of SPM emissions.

CO2 Emissions by The Transport
Sector and Traffic Demand Trends
Despite these apparent improvements,
passenger traffic in the transport sector has
been shifting continuously from energyefficient railways to energy-inefficient systems such as the private motor vehicles.
Figure 2 shows the changes in modal
share of inter-city passenger transport (passenger-km) between 1955 and 1994.
Motor vehicles have increased their shareat an accelerating rate since 1965, from
32% to 67%. For trips of 300 km or more,
air transport has gained a considerable
share due to growth of personal income
and the increase in the number of local
airports.
As shown in Fig. 3, the use of motor vehicles in urban transport has risen rapidly.
Clearly, motor vehicles have gained in
popularity for commuting and private
trips. Table 3 shows that energy consumption per passenger-km by road transport
in urban areas during rush hours is about
23 times that of railways, not to mention
the resultant chronic congestion and air
pollution. In contrast, Japanese railways
mainly use electricity for power, whichcauses less air pollution.
There is now a serious need to reduce theenvironmental impacts of the transport
sector by developing a well-coordinatedsystem that combines different modes
according to their advantages. For example, the railway can carry large numbers of people over short to medium
distances with high energy efficiency, air
has the overwhelming advantage of speed
over long distances, and roads are convenient for door-to-door continuity.

Copyright © 1998 EJRCF. All rights reserved.

Impact on Japan of Doubling of Atmospheric CO2 Levels

Item

Description

Air temperature

Mean annual temperature will rise 1°–2.5°C.

Precipitation

Mean annual precipitation will change between -5% and +10%.

Sea level

Levels will rise 10–20 cm in the Sea of Japan and 15 cm in the Pacific.

Extinction ofsome species

Warming will force some animals and plants to move northward or tohighland, but lack of habitat due to topography, urbanization and otherfactors may cause extinction.

Agriculture• Rice yield will increase in northern Japan and decrease in west Japan.
• Due to low self-sufficiency in food supply, Japan’s food supply anddemand will be affected by changes in production volume of exporting
countries.
• Temperature rise may cause magnesium and other minerals in rice todecrease, resulting in deterioration of taste.

Fishery

The southern limit of the range of salmon will move northward.

Hydrology and Increase in rainfall instead of snow and early snow melting will increase riverwater resources flows in winter and decrease them in spring, creating a risk of water shortages.
Coastal area

The rise in sea levels will erode coasts at an accelerated rate. Many sandbeaches in resort areas will disappear.

Tourism andrecreation

Earlier snow melting will shorten the ski season and affect tourism severely.
Also, coastal erosion will wash away many beach resorts.

Health• Health disturbances caused by heat, such as heat stress and heat stroke,
will increase, particularly among the elderly.
• Animal-vector diseases, such as malaria and dengue fever, will increase.
• The rise in maximum daily temperature will increase the death risk,
particularly among the elderly. Circulatory ailments will become theprimary cause of death.
• NOx emitted from automobiles and factories will react with UV to produce
photochemical smog which causes acute and chronic health damage,including respiratory diseases.

Table 2

Health Impacts of Air Pollutants
Item

Description

Nitrogen dioxide (NO2)Adverse effect on respiratory organs at high concentrations

Carbon monoxide (CO)Bonds with hemoglobin in blood to disturb oxygen transport

Sulfur dioxide (SO2)

Damages respiratory organs, causing asthma (the Yokkaichi asthma)

Particulates (SPM)

Builds up in lungs and trachea

Table 3

Energy Consumption of Different Transport Modes
Energy consumption

Rail

Auto

Bus

Per passenger-km

100

534

168

Air
—

Per passenger (between Tokyo and Osaka)

100

461

101

300

Per passenger in Tokyo Metropolitan Region(during peak hours)

100

2,343

150

—

The figures are indexed to rail = 100.

Japan Railway & Transport Review 18 • December 1998

13

Railways and The Environment (part 2)

Figure 3 Modal Share in Metropolitan Tokyo

Figure 2 Modal Share of Inter-city Passenger
Transport (passenger-km)

Automobiles
Automobiles

Railways

Aircraft

Transport share

Transport share

80%
60%
40%
20%
65

75

85

90

Year

Environmental Improvement
Policies in Transport Sector
The Japanese MOT has been studying anddeveloping a package of both technicaland institutional policies to address theissue of global warming (Table 4). The
strategy with the highest priority is emission control at source for motor vehicles.
However, the importance of other policy
measures, including diversion of traffic toenergy-efficient systems, control of motor vehicle use by area, date and/or timezone, public campaigns about the needto reduce CO2 emissions, and technological cooperation with other countries, are
all recognized. More precisely, short- andmedium-term measures up to 2010 include changing the automobile tax system, promoting the ‘eco-drive’ concept,
constructing and upgrading public transport systems, promoting their use, andstreamlining distribution systems. These
measures will evolve into long-term measures, including development of zeroemission vehicles (ZEV).
Recently, a variety of R&D efforts are underway to control emissions at source.
New technology is being developed in thefollowing main areas: (1) improving
engine thermal efficiency; (2) reducing

14

Pedestrian oron two-wheels

88

68

80%
60%
40%
20%
0%

55

Buses

100%

100%

0%

Railways

94

68

88

Commuting

68

Business

88

Private useYearacceleration resistance by cutting vehicle
weight; (3) reducing rolling resistance;(4) reducing energy loss in drive system,
such as transmission; and (5) modifying
engine design to burn alternative fuels.
Table 5 compares the major features of
new motor vehicles powered by conventional and alternative fuels. Comparedwith present vehicles, cars powered byfuel cells, electricity and natural gas haveexcellent prospects for reducing CO 2
emissions, but they still have to overcome
problems of limited driving range.
The railway industry is also making
extensive efforts to become more environment friendly. For example, since 1992,
JR East has been setting the goals shownin Table 6. In the fields of energy saving
and reduction of CO 2 emissions, themajor focus is on upgrading railcar
design and performance as well as on
power generation systems. Weight reduction, use of regenerative braking, andintroduction of variable voltage variablefrequency (VVVF) circuits are major partsof the effort to achieve higher energy efficiency. For example, JR East’s latest
Series 209 EMU has been improved asshown in Table 7 to achieve a 50%
reduction in energy consumption compared to its Series 103 predecessor. R&D

Japan Railway & Transport Review 18 • December 1998

into power generation involves development of more efficient and cleaner energy
sources. In addition, state-of-the art technologies are being developed, such aswaste heat recycling and commercialization of solar power generation. The 16
leading private railway companies are
increasingly using energy-saving vehicles(Table 8).

Assessing Effects of Environmental Improvement Measures
Generally, quantitative analysis conducted to assess the effects of environmental improvement measures by the transport
sector is designed to determine costs andbenefits. Two indicators: physical, suchas emitted amount of pollutant, and economic, such as damage to the national
economy caused by environmental degradation, are used. However, a major
problem is how to establish reliable andagreed base values for pollutant emissions
and social costs. Comparison of basevalues currently used in Japan shows considerable variation among published data;
the difference between the values is aslarge as 200% for CO2, 400% for NOx,
300% for SOx, and 1000% for CO (Table
9). This is caused by a number of factors,

Copyright © 1998 EJRCF. All rights reserved.

Table 4
including differences in vehicle age,model, and fuel in different studies, as well
as differences in statistical analysis methods. In any case, the fact remains thatthe most vital and important set of datafor policymaking are not available.
A similar situation exists in quantifying thesocial costs of air pollution. Althoughmuch research has been conducted in the
USA and Europe, there is no agreed uniform method to measure social costs.
Moreover, the measurement conditions
vary considerably between countries, resulting in great variation of social costs.
Similarly, there are practically no usefuldata on social costs available in Japan,
especially no measured data related to thesocial costs of global warming, which canbe used in the transport sector. To address this shortcoming, we applied thecontingent valuation method to measure
the social cost defined as the amount thatJapanese people would be willing to pay
for government policy measures tocounter both the positive and negative
effects on the Japanese environment andsociety (Table 1), caused by a rise in air
temperature of 1° to 2.5°C resulting froma doubling in the level of atmosphericCO2. A questionnaire prepared according to the US National Oceanic and Atmospheric Administration (NOAA)
guidelines was used to survey 1620
people in Tokyo, Nagoya, Osaka, Sendai,
Okayama, and Kumamoto. The survey
showed that respondents would only pay¥8235 per year to prevent global warming. This figure was then used to determine the social cost per tonne-carbon,
which came to ¥8320/t-C.
Although we hope that base value emissions will soon be made more precise andunified, current quantitative analysis
methods and data must allow for somedifferent possibilities, and failure to do so
could result in incorrect policy decisions.

Copyright © 1998 EJRCF. All rights reserved.

Global Warming Countermeasures Proposed by Ministry of Transport
Short- and medium-term policies (up to around 2010)

Technological

1 Development and proliferation of fuel-saving cars
• Accelerate development of Gasoline Direct Injection engine, lean-burnengine and diesel-powered cars.
• Develop and promote use of hybrid and electric cars.
2 Utilization of traffic demand management techniques
3 Urban development to encourage use of public transport systems• Plan and develop effective use of urban bus services.
• Accelerate development of rail and light rail transport systems.
• Enhance nodes between different transport systems.
4 Streamlining of physical distribution systems• Improve efficiency of truck transport by using Intelligent Transport
Systems (communal transport, optimum vehicle allocation, andcomputer-guided optimum route selection).
• Promote modal shift to rail and marine transport.
• Reduce on-land transport by constructing international container ports
at strategic locations.

Institutional

1 Modification of auto tax system• Reclassify automobile tax rates on basis of fuel economy, instead ofdisplacement, to encourage purchase of fuel-saving cars.
2 Expansion of subsidy system to encourage construction of rail and
LRT systems

Other

1 Promotion of 'eco-drive' concept• Stop engine while not moving.
• Drive at economic speeds on highways.
• Encourage car pools.
2 Promotion of international cooperation• Assist developing countries in development of urban transportation
systems and improvement of fuel economy.
3 Strengthening of environmental monitoring system focusing on greenhousegases
4 Promotion of resource recycling

Table 5Comparison of Major Features of Alternative-Fuel Cars

Vehicle type

NitrogenoxidesGasoline

Hydrocarbons
Solidand carbon particulatemonoxidematterCarbondioxide

Power

1.0

— Baseline Index —DieselMuch worse

Methanol Otto engine
Diesel engine
Natural gas (CNG)

SameMuch worse

BetterCruising
range

Worse

1.2

Same

Same

Same

Same

Same

0.5

Worse

Same

Same

Same

Worse

0.6

Same

Worse

Same

BetterWorse

0.2

Electric

Much better Much better Much better

BetterMuch worse

0.1

Fuel cell/electric

Much better Much better Much better

BetterMuch worse

0.1

1. The cruising range is expressed as an index where gasoline cars = 1.0(same tank capacity).
2. The CO2 emissions include the fuel production and consumption stages.
3. CO2 for methanol cars is produced when methanol is produced from natural gas.

Japan Railway & Transport Review 18 • December 1998

15

Railways and The Environment (part 2)

Table 6

JR East Environmental Improvement Measures (at 1996)
Item

TargetEnergy/CO2

To reduce energy consumption per unit traffic volume related
to train operation by 10% in or before FY2001. Also to
reduce CO2 emissions from own thermal power stations
by 10%.

NOx

To reduce NOx emissions from own thermal power stations
by 40% in or before FY2001.

Destruction of ozone layer

To convert 30% of air-conditioning equipment using
designated freon gases, to the non-freon type by FY2001.

Resource recycling

To increase the recycle rate of wastes produced fromconstruction work and factories to 70% and that of wastes
produced from stations and trains to 30% by FY2001.

Resource saving

To increase percentage of recycled paper in office paper
consumption to 90% and to reduce consumption of water
resources by 5% in or before FY2001.

Natural environment

To plant 30,000 trees each year.

Noise and vibration

To reduce noise in wayside areas (those designated as'areas equivalent to densely populated residential areas') of
the Tohoku/Joetsu Shinkansen Lines to 75 dB or less.

To review reduction targets in consideration of future research and technologicaladvancement (FY1984 as baseline year).

Table 7

JR East Equipment Performance Upgrades
Model

103 Series

Year of manufacture

1965–83

1991–

Weight36.3 t/unit

25.0 t/unit

Rheostatic control system

VVVF inverter control system

Dynamic brake/electromagnetic
straight air brake

Regenerative brake/electric command air brake,
unit brake system

Main circuit
Braking system

Regeneration rate
Energy consumption

Table 8

Approx.35%
100 (standard)

47

Energy-Efficient EMUs Introduced by Large Private Railway
Companies

As of March 1998

16

209 Series

No. of units

Percentage share of total

Lightweight cars

3,750

22.3%

Regenerative brake cars

10,13360.4%

Chopper control cars

6,742

40.2%

VVVF cars

3,182

18.9%

Japan Railway & Transport Review 18 • December 1998

Policy Analysis System LETS
The Low Emission Transportation System
Simulator (LETS) is designed primarily toassess the effects of environmental improvement measures for inter-city transport systems. It is based on the widelyused demand forecast model with somecustomization, and examines the macro
relationships between traffic demand andenvironmental impacts. The system
programme runs on a PC and produces
simulation results in 2 minutes. It measures the above effects by combining traffic data (passenger-km) obtained from thedemand forecast model with base values
for pollutant emissions and social costs.
The result can be used to estimate user
benefits that are consistent with the demand forecast.
Figure 4 shows the fundamental structureof LETS. The demand forecast sub-unit
for inter-city transport analyzes demandchanges caused by development of highspeed transport networks or increases/
decreases in fares and taxes. Another subunit quantifies changes in pollutant emissions from different transport modes, theincidence of traffic accidents, etc. Multiplying traffic data (passenger-km) from thedemand forecast sub-unit by emission
base values for respective transportmodes, gives the environmental pollution
loads and other data. A third sub-unit
measures changes in environmental pollution loads caused by development ofhigh-speed transport systems in monetary
terms to determine the external economic
effects of such development. The use ofmonetary units allows various environmental pollutant loads (e.g., CO2, NOx)
to be treated uniformly as social costs that
can then form the basis of cost/benefit
analysis.
The traffic demand forecast sub-unit uses
a four-stage estimation method based on
three types of trip (business, tourism,
other) and three transport modes includ-

Copyright © 1998 EJRCF. All rights reserved.

Table 9Comparison of Pollutant Emissions Base Values by Transport Mode
Pollutants

Automobiles

Rail

Air

CO2 (g-C/passenger-km)

27 – 46

5.2

41 – 53

NOx (g/passenger-km)

0.26 – 1.00

0.30

0.47

SOx (g/passenger-km)

0.016 – 0.041

0.018

0.209

CO (g/passenger-km)

0.094 – 0.930

ing air, rail, road (excluding bus).
Existing demand forecast models tend tounderestimate environmental impacts
because they fail to take induced traffic
into account. To address this shortcoming, LETS estimates induced traffic by linking different models at various stages
through accessibility variables. As a result, it can express induced traffic volumes
and changes in selection of destinations
due to reduced travel time caused by increased railway operating speeds. Moreover, LETS can analyze how traffic isaffected by decreases in disposable income caused by fare increases. Figure 5
shows the concept of the induced demand
generation process. The size of the circles
represents traffic volume, and the changes
in circle size show that traffic distribution
patterns change with the improvement oftransportation systems. In the diagram on
the left, trips starting in zone O are divided equally between three destinations:
A, B, and C. As improvement in the transport system reduces the travel time between zones O and A, more traffic is
induced in zone O (shown by a blackouter circle), leading to a significant increase in the number of trips to zone A.
The increase in total traffic volume spills
over to zone C, although the transportsystem from zone O to C has not been
improved, but trips from zone O to zone
B decrease because the transport to zone
B is less convenient than the other two
destinations.

Copyright © 1998 EJRCF. All rights reserved.

Analysis of
Policy Measures and Effects
This section describes the LETS simulation results based on the Japanese transport networks shown in Fig. 6. The
environmental improvement effects andsocioeconomic impacts of various policy
measures are compared assuming thatGDP grows at an annual rate of 2% while

the number of automobiles per household
grows at an annual rate of 1%. Table 10
summarizes the analyzed policy options,
option levels, and forecast results for2010.
If no environmental improvement measures are taken under the assumed conditions, total traffic volume expressed as
passenger-km will grow by 47% between
1990 and 2010, and generated traffic volume will grow by 43% for the same period. The modal shares for the generated
traffic volume are 67% for motor vehicles,
26% for rail, and 7% for air. Pollutant
emissions will increase by 45% for CO2,
47% for NOx, 42% for SOx and 49% for
CO.
Table 10 also shows the rates of change
in 2010 when improvement measures aretaken. First, improvement of rail services
to encourage a demand shift to rail, whichcauses relatively small environmental

Figure 4 LETS Components
INPUT

SYSTEMOUTPUT

Economic indicator
Level of services
OthersInter-city travel
demand forecast
modelRail / Air / Car

Trip generation
Trip attraction
Trip distribution
Modal split

Travel demandby traffic mode

Emissions of air
pollution by traffic unit

Total emission
by traffic mode
(CO2/NOx/CO/SOx)

Traffic accidents bytraffic unit

Traffic accident
volumeSocial costs by traffic
unitSocial costs
Global warming
Local pollution

User benefits using
demand model

User benefit values

Japan Railway & Transport Review 18 • December 1998

17

Railways and The Environment (part 2)

pollution loads, does not always contribute to environmental improvement because it induces additional demand atsome improved service level (e.g., a significant increase in train speed). Nevertheless, pollutant emissions per trip arealways reduced by a demand shift to rail.
Generally, any economic measure suchas increases in fares, tolls, taxes, etc., ismost effective in producing environmental improvements, but the resultant increase in travel costs may negatively
impact the utility (satisfaction) level oftransport users to some extent.
However, it should be noted that LETS
does not account for recycling of tax revenues. Consequently, effective investmentof taxes generated by economic measures
must be taken into account in the future.
Introduction of low-polluting cars is very
effective in improving the environment,suggesting the need for purchase incentives.
Although it is well known that railways
are clearly more environment friendly
than other transport modes, their main

Figure 5 Diagram Showing Induced Demand and Changing Traffic Distribution
OriginDestination

OriginDestination

A
O

A
O

B
C

B
C

advantage is their high transport efficiency, which should be the primary basis for deciding new construction.
The simulation results show that althoughstrict policy measures (higher option levels) may not stabilize CO2 emissions at
the 1990 level, meaningful improvement
can reasonably be expected by combination of pollution control measures atsource (e.g., promotion of low-pollutioncars) with effective measures to encourage demand shift to low-pollution transport modes such as rail.

A further analysis examined the effectiveness of two policy combinations: 1. Increasing operating speeds of inter-citylines along with increasing highway tolls;
and 2. Increasing operating speeds of inter-city lines and creation of the carbon
tax. The main purpose of this analysis is
to find how to achieve environmental
improvement without affecting the utility
level of transport users. Figure 7 shows
the relationship between social costs (related to global environment, local environment and traffic accidents) andTable 10 Effect of Environmental Improvement Measures in 2010
Indicators for evaluation
Policy options/
option levels

18

Social costof global
warming

Economic
effectTotal
passenger-km
carriedCO2emissions

+18%

-5%

+4%

-22

+17,155

+56%
+91%

-3%
-2%

+15%
+26%

-15
-11

+48,180+81,030

NOx
emissions¥100 million/ ¥100 million/
year
year

Increasing operating
speeds of inter-regionalrail service

Tokaido/Sanyo Shinkansen: 250 km/h
Other lines: 150 km/h
250 km/h for entire line
300 km/h for entire line

Raising toll charges
for all highways

Raise toll charge by 30%
Raise toll charge by 50%
Raise toll charge by 100%

-2%
-3%
-5%

-4%
-6%
-10%

-6%
-10%
-17%

-18
-29
-58

–1,825–2,920–8,030

Imposing fuel tax

Raise fuel price by 30%
Raise fuel price by 50%
Raise fuel price by 100%

-3%
-5%
-8%

-6%
-8%
-13%

-5%
-7%
-14%

-29
-47
-88

–2,555–4,015–8,030Developing of
low-pollution cars

Increase energy efficiency by 30%
Increase energy efficiency by 50%

—
—

-25%
-42%

-34%
-56%

-117
-193

—
—

Japan Railway & Transport Review 18 • December 1998

Copyright © 1998 EJRCF. All rights reserved.

Figure 6 Japanese Transport Networks as of 1998

Railways(Shinkansen and trunk lines)

Roads(Expressways)

Airports(Jet and conventional, four main islands only)

Sources: Ministry of Construction and Ministry & Transport

Copyright © 1998 EJRCF. All rights reserved.

Japan Railway & Transport Review 18 • December 1998

19

Railways and The Environment (part 2)

Figure 7 Economic Effects of Policy Combinations
1.5

Social cost change (¥100 million/day)

economic effects. Introduction of the
carbon tax on its own contributes to increased economic loss, but if it is combined with faster inter-city rail services,
positive effects are produced. This clearlysuggests that some options can achieveboth environmental improvement andhigher utility, depending upon taxation
rates, traffic conditions, and other relevant
factors.
The above analyses are useful for preliminary evaluation of various policy measures. However, at the same time, therelatively low precision of base values forpollutant emissions and social costs requires careful interpretation of the results.
For example, the highest CO2 base value
for automobile emissions is 70% higher
than the lowest value. When the former
value is used to evaluate the economic
effects of the carbon tax, users face ahigher tax burden because the tax is imposed on the basis of the weight of emitted carbon. The reverse is true when thelowest base value is used. The difference
has an impact on the results related to traffic demand, user benefits, and carbon tax
revenues, thereby influencing policy options.

Relationship between economic-effect change
and social-cost change

1.0Higher speed ofrailways (Level 2)

0.5
Base case
0
-0.5
-1.0

Higher speed of railways(Level 2), plus increases
in highway tolls

Increases inhighwaytolls
CO2 taxes-1.5Higher speed ofrailways (Level 2),
plus CO2 taxes

-2.0
-2.5
-50

0

50

100

150

Amount of economic effect(User utility + Passenger revenue + Tax revenue) (¥100 million/day)broad-based public discussion.
• To encourage open and fruitful discussion, formal communication routes
should be instituted between policymakers and the public.
• Since discussion of environmental
policy tends to be dominated by intransigent positions based on different opinions, efforts should be made to develop
a common viewpoint based on quantitative analysis using objective data.
More precisely, base values for pollut-

ant emissions and social costs should
be unified through research and extensive field measurement, and a national
consensus should be established onwhat values to use as the basis for discussion. Finally, forecasting models
must be made more accurate.
■

Conclusion
As a concluding remark, we would liketo point out major issues to be addressed
for effective evaluation and implementation of policy options.
• Many policy measures in the transport
sector tend to evoke trade-offs between
improvement of convenience/economic development and environmental preservation/improvement. This is
attributable primarily to lack of assessment of possible measures, and poor
communication with affected parties.
To ensure timely selection and implementation of effective measures, policy
options (including scenarios) and evaluation results must be made available for20

Japan Railway & Transport Review 18 • December 1998

Haruo Ishida
Dr Ishida obtained his doctorate from the Civil Engineering Department of Tokyo University. He iscurrently a professor at the Institute of Policy and Planning Studies at Tsukuba University. He is theauthor of The Environment and the Car Society (in Japanese), 1995.

Seiji Iwakura
Dr Iwakura graduated from the Civil Engineering Department of the Science University of Tokyo andobtained a Ph.D. in Engineering from the Tokyo Institute of Technology. He joined Kikaku Kaihatsu
Co., Ltd. in 1988, but returned to the Institute in 1989. He was appointed Project Manager at theJapan Institute for Transport Policy Studies in 1994, and has been a part-time lecturer at the Science
University of Tokyo since 1998.

Copyright © 1998 EJRCF. All rights reserved.