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Hot, congested, crowded and diverse: Emerging research
agendas in planning
Hilda Blanco
a,1,
*, Marina Alberti
a,1
a
Department of Urban Design and Planning, Box 355740, University of Washington, Seattle, WA 98195-5740, USA
Ann Forsyth
b,2
, Kevin J. Krizek
c,2
, Daniel A. Rodrı
´guez
d,2
b
Department of City and Regional Planning, 106 West Sibley, Cornell University, Ithaca, NY 14850, USA
c
Department of Planning and Design, University of Colorado, Denver, Campus Box 126, POB 173364, Denver, CO 80217-3364, USA
d
Department of City and Regional Planning, CB 3140, University of North Carolina, Chapel Hill, NC 27599-3140, USA
Emily Talen
e,3
, Cliff Ellis
f,3
e
School of Geographical Sciences and School of Sustainability, Arizona State University, PO Box 875302, Tempe, AZ 85287-5302, USA
f
Department of Planning and Landscape Architecture, Clemson University, 124 Lee Hall, Box 340511, Clemson, SC 29634-0511, USA
Abstract
This special issue explores emerging research agendas in planning. It brings together scholars from diverse schools working on
new areas of research and application in urban design and planning. Emergent research agendas include both novel areas of research
and important shifts in the direction of a research area. The challenge for planning schools is to reflect critically on these changes
and develop long-term research agendas that can better position our field in society and academia, and provide a basis from which to
assess our academic programmes. The chapters presented in this issue reinforce key aspects of planning: multi-scale, and multi-
faceted, yet integrative in its intent, stressing the physical, yet inescapably social. At the same time, they identify research areas that
respond to major social and environmental changes. Blanco and Alberti focus on the latest findings in climate change science and on
planning for adaptation; they highlight the opportunities that planners have to provide leadership in this area. Forsyth, Krizek and
Rodrı
´guez take up the issue of non-motorised travel, a topic of increasing interest for urban designers, public health experts and
transportation and energy planners. For Talen and Ellis, an emerging challenge is the need to plan for diverse and compact
communities. What social factors, policies, programmes and planning processes facilitate compact and diverse communities?
#2009 Elsevier Ltd. All rights reserved.
Keywords: Climate change adaptation; Urban planning and climate change; Non-motorised; Walking and cycling; Social diversity; Compact
development
www.elsevier.com/locate/pplann
Progress in Planning 71 (2009) 153–205
* Corresponding author. Tel.: +1 626 356 9064; fax: +1 626 356 9064.
E-mail addresses: hblanco@u.washington.edu (H. Blanco), malberti@u.washington.edu (M. Alberti), forsyth@cornell.edu (A. Forsyth),
krizek@colorado.edu (K.J. Krizek), danrod@unc.edu (D.A. Rodrı
´guez), etalen@asu.edu (E. Talen), cliffoe@clemson.edu (C. Ellis).
1
Guest Editors, authors of the Introduction and Chapter 2.
2
Authors of Chapter 3.
3
Authors of Chapter 4.
0305-9006/$ – see front matter #2009 Elsevier Ltd. All rights reserved.
doi:10.1016/j.progress.2009.03.001
Contents
Chapter 1. Emerging research agendas in planning . . . ........................................... 155
Chapter 2. Building capacity to adapt to climate change through planning . . . .......................... 158
2.1. Introduction . . . ................................................................ 158
2.2. Adaptation and mitigation . . ....................................................... 158
2.2.1. What does adaptation mean? . . ............................................... 159
2.2.2. Adaptation to what? IPCC projections . . . ....................................... 160
2.2.3. The relation of adaptation to natural hazards mitigation .............................. 161
2.2.4. The relation of climate change adaptation to sustainable development . . .................. 162
2.3. Planning for adaptation ........................................................... 163
2.3.1. Planning analysis: The science of climate change adaptation . .......................... 163
2.3.2. The planning process and urban adaptation plans ................................... 164
2.3.3. Identifying and designing strategies . ........................................... 167
2.3.4. Assessing strategies ....................................................... 168
2.3.5. Implementation issues . . . ................................................... 168
2.3.5.1. Institutional. . . ................................................... 168
2.3.5.2. Financial ....................................................... 169
2.3.5.3. Legal . . . ....................................................... 169
2.4. Conclusion: Opportunities for the profession . ........................................... 169
Chapter 3. Non-motorised travel research and contemporary planning initiatives . . ...................... 170
3.1. Introduction . . . ................................................................ 170
3.2. Rise and prominence of walking and cycling issues ....................................... 170
3.2.1. Traffic congestion. . ....................................................... 170
3.2.2. Environmental conservation . . . ............................................... 172
3.2.3. Health . ................................................................ 173
3.2.4. Liveability . . ............................................................ 174
3.3. Importance of considering walking versus cycling separately. . . .............................. 174
3.4. Specific issues requiring further research............................................... 176
3.4.1. Theory ................................................................ 177
3.4.2. Measurement and methods . . . ............................................... 179
3.4.3. Behaviours . ............................................................ 179
3.4.3.1. If you build it, will they come? . ....................................... 180
3.4.3.2. Substitution—will people drive less or exercise more? . . ...................... 180
3.4.3.3. Changing rooms and cargo—what are the barriers? .......................... 181
3.4.3.4. Route choices—where to go? . . ....................................... 181
3.4.3.5. Chained trips and interface with other modes .............................. 181
3.4.3.6. Excess travel and pedestrians—travel to closest destinations? . .................. 181
3.4.3.7. The role of preferences and lifestyles—does the built environment matter,
for whom? . . . ................................................... 182
3.4.3.8. Where behaviours occur—policies around home, work, school or commercial
areas?. . . ....................................................... 182
3.4.4. Policy and practice . ....................................................... 182
3.4.4.1. Including NMT in transportation-land use models and regional funding processes..... 182
3.4.4.2. Policy levers and audience—evidence for whom? . .......................... 182
3.4.4.3. Expanding benefits and outcomes . . . ................................... 183
3.5. Conclusions . . . ................................................................ 183
Chapter 4. Compact and diverse: The future of American urbanism.................................. 184
4.1. Introduction . . . ................................................................ 184
4.1.1. Why are some urban places diverse? ........................................... 185
4.1.2. Policies and programmes to increase diversity . . ................................... 187
4.1.3. Planning processes that support diversity. . ....................................... 188
4.1.4. Diversity and city form: The role of urban design and physical planning .................. 191
4.2. Research questions . . ............................................................ 193
4.2.1. Why are some existing urban places diverse? . . ................................... 193
4.2.2. What policies and programmes are likely to promote diversity? . . . ...................... 193
H. Blanco et al. / Progress in Planning 71 (2009) 153–205154
4.2.3. What planning processes are likely to promote diversity? . ............................ 194
4.2.4. How can we build new neighbourhoods, districts and towns that support diversity? What design
patterns will work? . . . ..................................................... 194
4.3. Conclusion . ....................................................................194
References . .......................................................................... 196
Biographical details. . . .................................................................. 204
Chapter 1. Emerging research agendas in
planning
Hilda Blanco and Marina Alberti
This is the first of two planned special issues in
Progress in Planning exploring emerging research
agendas in planning. The idea for this topic evolved out
of a strategic planning effort we undertook for the
interdisciplinary PhD programme in Urban Design and
Planning at the University of Washington. As we began
the planning process, we identified major changes that
have occurred in society and in the field since our
programme was developed and its curriculum set. We
recognised that, in general, the challenge for planning
schools is to reflect critically on these changes and
develop long-term research agendas that can better
position our field in society and academia, and provide a
basis from which to assess our academic programmes.
As a result, we first established a seminar called
‘Emerging research agendas’, where panels of faculty
and students lead seminars on the directions of research
emerging in various existing or emerging research
clusters.
Through the seminar, we realised that this effort
should be broader, going beyond our faculty and our
PhD programme. These special issues aim to explore
emerging research agendas in the planning discipline by
bringing together scholars from diverse schools or fields
working on new areas of research and application in the
field of urban design and planning. Emergent research
agendas include both novel areas of research as well as
important shifts in the direction of a research area. We
were pleased to obtain over three dozen abstracts to our
announcement and we issued about a dozen invitations
for authors to submit complete chapters on promising
topics. This first issue contains three chapters that
display the different scales and fields of planning, from
research opportunities in climate change adaptation,
that calls for a comprehensive approach with multiple
facets, to narrower topics within a field of planning,
such as non-motorised travel, which planners typically
classify under the field of transportation but with
connections to public health and energy planning, and
planning for diverse and compact communities, with
strong urban design and social psychology aspects.
The chapters identify research areas that respond to
major social and environmental changes. Blanco and
Alberti focus on the latest findings in climate change
science. These findings conclude that, regardless of
mitigation efforts, because of a time lag in the ocean’s
response to atmospheric temperature, the world will
experience severe impacts of climate change during this
century. Heeding the call that we need to prepare now
for these impacts, Blanco and Alberti focus on planning
for adaptation and highlight the opportunities that
planners have to provide leadership in this area. Forsyth,
Kreizek and Rodrı
´guez take up the issue of non-
motorised travel, a topic of increasing interest for urban
designers, public health experts and transportation and
energy planners. Given that motorised transportation
requires energy which is often polluting, that public
health experts have been urging us to walk or bicycle
more for our health, as well as other reasons, Forsyth
and her colleagues argue that in order to assess the
contribution that non-motorised travel can make to our
ways of life, we need research on conceptual models,
methods, behaviours, and policy options. For Talen and
Ellis, an emerging challenge is the need to plan for
diverse and compact communities. More ecological
ways of living may require more compact communities,
people living in closer quarters. At the same time, the
population in many parts of the world, as in the USA, is
increasingly diverse. Differences at close quarters often
engender conflict. What social factors, policies,
programmes and planning processes facilitate compact
and diverse communities?
Building capacity to adapt to climate change
through planning
Relying on the fourth synthesis report (2007) of the
Intergovernmental Panel on Climate Change (IPCC),
Blanco and Alberti’s chapter makes the case that climate
change is ‘unequivocal’, probably caused by anthro-
pogenic release of greenhouse gases, and that our policy
H. Blanco et al./ Progress in Planning 71 (2009) 153–205 155
response, which has been focused on mitigating the
emission of greenhouse gases, must now become dual:
mitigating the causes, and adapting to the impacts of
climate change. The first parts of this chapter review the
climate change literature on adaptation and briefly set out
the major impacts of climate change which we can
expect. A discussion of the relation of climate change
adaptation to natural hazards mitigation planning and
sustainable development follows.
The chapter then reviews the relevant literature and
develops a planning research agenda for adaptation
to climate change paralleling the planning process,
which identifies a range of opportunities for planning
researchers. First, with their knowledge of land use and
land cover, planning researchers can collaborate with
climate scientists to downscale global climate change
models to make them applicable at the regional and
local levels. Once the regional impacts have been
determined, planners can develop adaptation plans, at
an urban, sectoral or project scale. The chapter reviews
early models of such planning efforts. Adapting to
climate change has irreducible uncertainties, which
will require innovative ways to manage risk. Some
innovative responses have been developed, and are
beginning to be applied, e.g., scenario-based and
stakeholder involvement and robust decision-making
approaches. Adaptation strategies to various impacts
need to be identified and developed, including protec-
tion strategies, involving technical engineering solu-
tions, accommodation strategies, involving changes in
regulations and programmes, and retreat and abandon-
ment strategies, which require large-scale policy
changes. In addition, adaptation strategies need to be
evaluated. How should this be done? What are the
strengths and weaknesses of traditional assessment
methods, such as cost–benefit analysis, cost-effective-
ness, multi-criteria evaluation, when applied to climate
change strategies? Planning researchers can also focus
on implementation issues, anticipating institutional,
fiscal and legal obstacles, as well as evaluating the
preparation and implementation of adaptation plans.
Non-motorised travel research and contemporary
planning initiatives
Forsyth, Krizek, and Rodrı
´guez focus on the promise
of non-motorised travel (NMT), particularly walking
and cycling, to reduce automobile use. They review a
growing body of literature that promotes NMT, and
studies their determinants and secondary benefits. They
point out that much, however, remains unknown about
walking and cycling. What individual and environ-
mental factors spur increased use of these two modes?
Are the factors similar or different? To what extent?
Under what circumstances? What policy concerns can
increased walking and bicycling help remedy? The
enthusiasm generated over NMT has created a need for
evidence on the extent to which different policies have
succeeded in inducing walking and cycling travel and
producing other benefits for communities.
This chapter explains why walking and cycling are
rising in prominence as potential strategies to solve
problems of traffic congestion, environmental con-
servation, health and livability. Focusing on adult
populations, it distinguishes between walking and
cycling, emphasising differences, including: who
participates, the geographical range of movement,
speed, needed infrastructure, responsibilities for
planning that infrastructure, trip purposes, safety
concerns, and barriers. Finally, it identifies research
opportunities from the current knowledge base, while
outlining effective strategies for why and how research
on non-motorised issues could best be positioned in the
future. Relevant areas include: theory, measurement
and methods, behaviours, and policy. Overall there is a
need to refine theories and data collection, improve
research designs, and develop a base of evidence on
walking and cycling to support more robust, realistic
and targeted policy prescriptions.
Compact and diverse: The future of American
urbanism
Talen and Ellis address a defining phenomenon of
urban growth and change in the 21st century—the
intensification of social diversity in conjunction with
growing pressure to live more compactly. They point
out that greater social mix will occur in urban places
with limited capacities to expand further outward, due
to the environmental, economic and social costs
associated with sprawl. Development pressure on
existing urban places, especially those that are well
serviced by transit, will result in much higher land costs,
making it that much more difficult to accommodate a
society increasingly stratified by race, ethnicity, class,
age, household type and other social factors. The result
is likely to be not only further displacement and
isolation of low-income populations, but also the rise of
an urban pattern defined by spatial segregation of
various kinds.
Talen and Ellis point out that, while social scientists
grapple with the racial, ethnic and class tensions this
growing diversity entails, urban planners have yet to
formulate a well-reasoned response to the issues
surrounding social diversity in the urban context. The
authors find this curious, given that a vibrant social mix is
H. Blanco et al. / Progress in Planning 71 (2009) 153–205156
both a normative goal of planners and a significant
challenge to urban stability. Growing dissatisfaction with
the lack of well-serviced urban places capable of
accommodating a diverse society will require urban
planners to shift focus. Specifically, Talen and Ellis
identify the emergence of four broad areas of research
that have previously been only weakly developed. First,
the need to better understand existing diverse commu-
nities, i.e., why some places, despite opposing pressures,
manage to be both compact and diverse.A second area of
research could focus on identifying policies and
programmes that are effective in sustaining and promot-
ing environments that are diverse and compact. The third
research area concerns the planning process itself. That
is, what planning processes can be formulated to
encourage and sustain social diversity in urban places?
Finally, the fourth research area involves assessing the
role of urban design and physical planning in accom-
modating diversity, with a focus on developing a practical
catalogue of patterns, models, examples and standards
for use by planners and designers during the coming
decades of rapid urban growth. In this area, Talen
and Ellis argue, research should address issues such
as neighbourhood structure, housing mix, civic
spaces, defensible space, school location, and land use
patterns.
Highlighting the dual nature of urban planning, the
chapters in this issue are a blend of the physical and the
social. For Blanco and Alberti, adaptation planning is
regionally and locally grounded, and, given the
uncertainty of impacts, the planning process needs to
be based in science and analysis and be broadly
participatory, paying attention to institutional, fiscal,
legal as well as regulatory factors. In the case of non-
motorised travel, we cannot get more physical than
reengaging people on foot or on a bicycle with their
communities. And yet, this increasing societal interest
in non-motorised travel is probably affected by social,
economic and psychological factors. The very topic of
Talen and Ellis—diverse and compact—underlines the
interconnection between the physical and the social that
is inescapable in planning.
This multi-author monograph reinforces key aspects
of planning: multi-scale, and multi-faceted yet integra-
tive in its intent, stressing the physical, yet inescapably
social. At the same time, the authors identify opportu-
nities for planning academics and the profession to
engage in research on emerging issues of central
importance for our times. Such research can contribute
to a reinvigorated planning practice providing the
leadership needed to confront the planning challenges
of the 21st century.
H. Blanco et al./ Progress in Planning 71 (2009) 153–205 157
Chapter 2. Building capacity to adapt to climate
change through planning
Hilda Blanco and Marina Alberti
2.1. Introduction
The Intergovernmental Panel on Climate Change
(IPCC) Fourth Assessment Report (AR4) (IPCC,
2007a: 5) concludes that the ‘warming of the climate
system is unequivocal’ and that ‘Most of the observed
increase in globally averaged temperatures since the
mid-20th century is very likely [assessed likelihood
over 90%] due to the observed increase in anthro-
pogenic greenhouse gas concentrations’ (p. 10). The
major policy response around the world, including
that of the Kyoto Protocol, thus far has focused on
efforts to reduce or mitigate the emission of green
house gases (GHGs) to avoid the predicted worst
possible warming scenarios. But, even if we succeed
in capping GHGs to 2000 levels, there is a time lag in
the oceans’ response to atmospheric temperatures, and
temperature and sea levels will continue rising for
another century. Adapting to climate change is
increasingly being recognised as equally important
as reducing the anthropogenic causes of climate
change (IPCC, 2007a: 17). And adapting to climate
change is at its core a call for planning. As such, it
provides the planning profession with opportunities to
provide leadership in responding to this great global
challenge.
This chapter begins with an account of adaptation,
including its meaning and the likely impacts to
whichwewillneedtoadapt.Wealsoexplorethe
linkage of climate change adaptation to the related
fields of natural hazards mitigation and sustainable
development. The chapter then discusses how,
although much of the recent interest in adapting to
climate change is focused on adaptation strategies,
adapting to climate changes provides broader and
multiple opportunities for planning research. The rest
of the chapter sketches out the many roles that
planners can play, and reviews the existing research in
these areas. These areas include: the emerging
science of climate change adaptation, including
vulnerability assessments; an integrative and strategic
planning process based on collaborative scenario
development; the identification and development of
adaptation strategies; evaluation research focused
on such strategies; and, finally, research on imple-
mentation issues, including institutional, fiscal and
legal.
2.2. Adaptation and mitigation
Although the UN Framework Convention on
Climate Change (1992) identified two responses to
climate change, mitigating change through the reduc-
tion of greenhouse gas emissions and adaptation to its
impacts, not until IPCC’s third assessment report
(IPCC, 2001a) did the subject of adaptation begin to
receive separate and adequate attention in the assess-
ments. The major IPCC policy focus has been the
mitigation of GHGs, and, as indicated, this has also
been the focus of the major global treaty to address
climate change, the Kyoto Protocol. Technological and
economic issues have been the main concerns of
research on mitigation, a research focused on global-
scale, top-down aggregate modelling. Although a
smaller effort, there is a growing body of research
focused on adaptation that emphasises local and place-
based analysis, and uses approaches more akin to
development studies and disaster and natural hazards
risk mitigation.
The increasing evidence for climate change, and the
lack of adequate action on mitigation, has brought
renewed emphasis on adaptation policies. The IPCC
Fourth Assessment of mitigation efforts ‘shows that
current commitments would not lead to a stabilization
of atmospheric greenhouse-gas concentrations,’ and
that, due to lag times in the climate system, ‘no
mitigation efforts, no matter how rigorous and relent-
less, will prevent climate change from happening in the
next few decades’ (IPCC, 2007b: 748). During this
century, regardless of mitigation efforts, we will either
suffer the adverse impacts of, or successfully adapt to,
climate change.
Mitigation and adaptation, however, do not pose
either/or policy decisions—both are needed. Without
successful mitigation measures, the magnitude of
climate change may be so great as to make adaptation
strategies ineffective. Successful ‘mitigation reduces
the adaptation challenge’ (IPCC, 2007b: 750). But the
Fourth Assessment report makes clear that the relations
and interrelations between mitigation and adaptation
efforts are only beginning to be examined; research
results thus far indicate that the relations are not
straightforward, and that such efforts may be difficult to
integrate (IPCC, 2007b: 752–760, 770–771).
Since IPCC reports cast their projections in terms of
emission scenarios ending in 2100, a common percep-
tion is that we will not experience the worst impacts
until 2100, and that we have almost a century to prepare.
But even though mean global temperature rise over the
next centuries may be gradual, the frequency of episodic
H. Blanco et al. / Progress in Planning 71 (2009) 153–205158
climate events, such as droughts, floods and heatwaves,
may increase significantly much before the end of the
century. And not all impacts of climate change are
gradual, some may be abrupt. In addition, some
adaptation strategies may require institutional capacity
and financing that require time for planning and
implementation.
Planners have roles to play in mitigating greenhouse
gas emissions, through land use policies that reduce
vehicle travel, building standards that reduce the need
for cooling and heating, encouraging the use of
alternative energy sources, and other related policies.
And, cities in the US have increasingly taken leadership
in reducing greenhouse gases. At the end of 2007,
mayors of over 700 cities in US had signed a pledge to
meet or surpass Kyoto targets to reduce GHGs, and to
lobby their states, and the federal government, to adopt
such policies. However, mitigation measures require
global action to be effective, and national and
international policies will be required to achieve
stabilisation of greenhouse gases. On the other hand,
adaptation policies are more closely tied to the local and
regional level, since impacts, strategies and benefits are
local. Thus, adaptation planning is the type of planning
that fits naturally the agenda of urban and regional
planning. And adapting to extreme impacts of climate
change is fundamentally a planning challenge, which is
likely to call for public, community-wide planning and
not just individual or autonomous adaptations.
2.2.1. What does adaptation mean?
In the climate change literature, adaptation is defined
in the context of vulnerability, sensitivity and adaptive
capacity. Vulnerability is often defined as the propensity
of human and ecological systems to suffer harm, and
adaptive capacity as their ability to respond to stresses
as a result of climate change effects. Sensitivity refers to
the degree to which a system is affected by climate
change impacts. Adaptive capacity is seen as a function
of behaviour, resources and technologies. Vulnerability
is seen to be influenced by development path, physical
exposure, distribution of resources, prior stresses and
social and government institutions (IPCC, 2007b: 720).
The concept of resilience is seen as the ‘flip side of
vulnerability—a resilient systems or population is not
sensitive to climate variability and change and has the
capacity to adapt.’ (IPCC, 2001b: 89). Fu
¨ssel and Klein
(2006;Fu
¨ssel, 2007) have argued for an integrative
concept of vulnerability that incorporates two factors:
an external dimension responding to the exposure of a
system to climate impacts; and an internal dimension
corresponding to a system’s sensitivity and its adaptive
capacity. IPCC’s AR4 definition of vulnerability
follows this integrative concept:
Vulnerability is the degree to which a system is
susceptible to, and unable to cope with, adverse
effects of climate change, including climate varia-
bility and extremes. Vulnerability is a function of the
character, magnitude, and rate of climate change and
variation to which a system is exposed, its sensitivity,
and its adaptive capacity. (IPCC, 2007b: 883)
Adaptation then becomes defined as the adjusting of
systems, natural or human, in response to actual or
expected impacts of climate change, such as sea level
rise, to reduce vulnerability or increase resilience in
response to observed or expected changes in climate
and associated extreme events (IPCC, 2007b: 869).
Vulnerability is also inherently connected to the concept
of risk, which is typically defined as the combination of
the magnitude of the impact with the probability of its
occurrence. Risk refers to the uncertainty in the
processes of climate changes (IPCC, 2007b: 782).
The recent IPCC assessments, however, acknowledge
the lack of common metrics for vulnerability or risk
assessments. Adaptive capacity also remains a cloudy
issue, although there is wide agreement that some
dimensions of adaptive capacity are generic and others
specific to particular climate change impacts (IPCC,
2007b: 727).
Smit, Burton, Klein, and Wandel (2000) unpack the
concept of adaptation further, by posing the related
questions and key variables:
Adaptation to what? The what are climate-related
stimuli, which can be expressed as climate or weather
conditions, e.g., sea level rise, or as ecological effects,
such as drought, or human impacts, e.g., crop failures
over the relevant time period.
Who or what adapts? Systems adapt, and concern
here is with the characteristics of a system related to
its adaptive capacity. The systems involved can be
human or ecological systems, cities or wetlands, or
sectors, such as transportation systems.
How does adaptation occur? Adaptations can occur in
multiple ways. Types of adaptation include reactive,
versus anticipatory, autonomous or planned. They can
be short- or long-range, localised or regional. They
‘can be distinguished according to whether they are
technological, behavioural, financial, institutional or
informational.’
How good is the adaptation? This calls for the
evaluation of a system’s adaptation, which invol-
ves identifying evaluation criteria, principles or
H. Blanco et al./ Progress in Planning 71 (2009) 153–205 159
processes for evaluating adaptations (Smit et al.,
2000: 229–245).
We address many of these aspects of adaptation in
the sections below.
Biological adaptation is reactive, that is, organisms
react to an external change after the change has
occurred. Individual and societal adaptations to climate
change can be reactive, e.g., emergency response, or
they can be proactive, anticipating the expected
impacts. According to the IPCC, reviews indicate that
reactive adaptation to climate change impacts may be
‘inefficient or unsuccessful in addressing irreversible
damage’ (IPCC, 2007b: 721). Anticipatory adaptations
are typically planned adaptations. Although the high
cost of adaptations to climate change may deter
adaptation efforts, the recent IPCC report recommends
that adaptive capacity can be improved ‘by including
adaptation measures in land-use planning and infra-
structure design’, as well as by ‘including measures to
reduce vulnerability in existing disaster risk reduction
strategies’ (IPCC, 2007b: 20). Thus, not only is
planning at the heart of anticipatory adaptation, but
major elements in urban and regional planning are
recognised as essential to improving adaptive capacity.
2.2.2. Adaptation to what? IPCC projections
The major impacts of climate change, to which we
will need to adapt, are changes in temperature, sea level
rise, precipitation change, and extreme events.
Temperature change. According to the latest IPCC
reports the change is projected to be: a global
warming of about 0.2 8C/decade for a range of
emission scenarios (with higher than average warm-
ing for North America) (IPCC, 2007c: 12).
Sea level rise. Model-based projections of global
average sea level rise by the end of the 21st century
are from 0.18 to 0.59 m for a range of emission
scenarios but excluding future rapid dynamical
changes in ice flow (IPCC, 2007c: 13) [our emphasis].
Precipitation change. Average mean precipitation is
very likely to increase in high latitudes and likely to
decrease in most subtropical land regions (IPCC,
2007c: 16); snow cover is projected to contract (IPCC,
2007c: 15).
Extreme events. It is ‘very likely that hot extremes,
heat waves and heavy precipitation events will
continue to become more frequent’ (IPCC, 2007c: 15).
The Fourth IPCC Assessment Report conditions its
model-based projections of sea level rise with the
phrase, ‘but excluding future rapid dynamical changes
in ice flow’. This is worth discussing briefly. Research
on the increasing rate of the melting of the Greenland
glaciers and Antarctic ice shelves was just emerging at
the time of the AR4 preparation, and the climate change
models do not reflect such changes. Today, the rapidity
of the observed changes in ice flow has led some
researchers to question the AR4 projections (Dowdes-
well, 2006; Kerr, 2006;Rignot & Kanagaratnam, 2006)
and to project mean sea level rise of up to 1.4 m or more
by 2100 (Hansen, 2007; Rahmstorf, 2007).
Note also the importance of temporal scales in
interpreting these impacts. IPCC impacts are stated in
terms of long-term trends, e.g., mean temperature
increases. A common misperception is that we will
experience such changes in a gradual way. But these
long-term trends are subject to variability around the
norms. Beyond normal variability, climate change
variability can be compounded by shifts in the very
shape of the frequency/probability distributions of
climate variables, e.g., El Nin
˜o Southern Oscillation
(ENSO) or volcanic eruptions or storms (Schneider,
Easterling, & Mearns, 2000;Smit et al., 2000). This
type of compounded variability can generate more
frequent extreme events, such as more intense
hurricanes. The magnitude of impacts will also vary
according to the specific characteristics of a region or
place. Some regions, for example, are highly likely to
experience a temperature increase three times the global
mean increase, up to a 6 8C increase. Other regions will
experience greater than normal inundations to sea level
rise because of land subsidence or erosion.
The major global impacts cited above are too general
to help us craft adaptation strategies. In order to design
such strategies, we will need to develop regional scale
climate change models, with specifics on regional
precipitation patterns, coastal characteristics, including
land and settlement patterns, geomorphology, water
resources, weather patterns, and related variables.
Based on such data, regional models could be linked
to global climate change models to determine more
place-based climate change impacts for a region. Local
and regional impact projections are necessary to begin
to determine a region’s vulnerability.
In the US, the first nationwide assessment of
climate change impacts was initiated in 1997. It
sponsored 18 regional assessments, and provided a
range of estimates based on two larger-scale models
for several sectors of the economy, as well as for large
regions of the country: Northeast, Southeast, Midwest,
Great Plains, West, Pacific Northwest, Alaska, and the
Islands. The assessment concluded that temperature
H. Blanco et al. / Progress in Planning 71 (2009) 153–205160
changes in the US will average 5–9 8F over the course
of the 21st century, or 3–5 8C, more than the projected
global increase (National Assessment Synthesis
Team, 2001). An update to this report, Global climate
change impacts in the United States, is currently
undergoing public review (US Climate Change
Science Program, 2009). These reports do not directly
address the impacts of climate change on cites. But, to
illustrate the inevitability and magnitude of adaptation
challenges in the decades to come, let us examine
climate change impacts on sea level rise, the type of
impact that will directly impact coastal communities
and their habitats in the continental US. Titus and
Richman (2001) conducted a spatial analysis of
coastal areas in the Atlantic and Gulf areas prone
to tidal inundations, which was incorporated into the
national assessment. Their analysis maps coastal
areas in elevation contours. Although this mapping
does not take into account erosion and other impor-
tant variables that could result in a more adequate
projection of future shorelines, the 1.5 m contour
mapping provides a rough estimate of areas inundated
at high tide if the sea rise were to rise by 50 cm. Titus
and Richman’s research reveals that four states in the
Atlantic and Gulf areas will be most impacted by sea
level rise over the coming century: Florida, Louisiana,
Texas and North Carolina, accounting for 80% of the
lowlands, and that, in total, 22,254 square miles
(amounting to the areas of Massachusetts, Vermont
and Delaware), would be below the 1.5 m contour and
at risk of tidal inundation over the next two centuries
4
(Titus & Richman, 2001: 28). Beyond inundation and
outright land loss, other key impacts of sea level rise
include: wetland displacement, shoreline erosion,
more severe storm-surge flooding, saltwater intrusion
into estuaries and freshwater aquifers, altered tidal
range in rivers and bays, changes in sedimentation
patterns, and decreased light penetration to benthic
organisms (McG Tegart, Sheldon, & Griffiths, 1990).
These other impacts of sea level rise make it clear why
local/regional analyses are crucial for adaptation
planning, since tracing the relevant impacts of sea
level rise for a community requires local knowledge
of wetlands, erosion rates, estuaries, aquifers, river
tides,andsoon.
2.2.3. The relation of adaptation to natural hazards
mitigation
The literature of planning for adaptation to climate
change is not extensive, has been focused on conceptual
issues (Fu
¨ssel, 2007;Fu
¨ssel & Klein, 2006;IPCC,
2007b: 749; Smit et al., 2000;Smit & Wandel, 2006),
and more recently has begun to document case studies
of adaptation practices (IPCC, 2007b: 721–724). As
already indicated, the literature shares the research
approaches of development studies and disaster risk
management. Since natural hazards mitigation planning
is a growing research area in planning, in this section we
will explore the relation of natural hazards mitigation to
adaptation planning.
Natural hazards mitigation planning and planning
for climate change adaptation, as indicated, share the
conceptual framework of vulnerability assessment. In
both fields, however, vulnerability measures are still
evolving. In the climate change literature, Fu
¨ssel and
Klein (2006), in a recent review article on vulnerability
assessments, argue that vulnerability assessments have
been changing to incorporate a more sophisticated
approach to vulnerability, moving beyond impact
assessment of climate change to vulnerability assess-
ments focused on mitigation, and more recently to
adaptation policy assessments. They point out the
ambiguities involved in the concept of vulnerability,
and identify three main models for conceptualising and
assessing vulnerability: (a) the risk hazard framework,
the more technical approach which conceives ‘vulner-
ability as the dose-response relationship between an
exogenous hazard to a system and its adverse effects’;
(b) the social constructivist framework dominant in
political economy and human geography, which focuses
on social vulnerability and conceives it as an inherent
condition of households or communities determined by
socio-economic and political factors, clearly emphasis-
ing non-climatic factors in vulnerability; and (c) a more
integrative concept of vulnerability, such as the concept
used in the IPCC’s Fourth Assessment Report, which
incorporates external and internal dimensions, as
discussed in Section 2.2.1. The natural hazards
literature is also evolving towards a more integrative
framework (McEntire, 2005), but currently the domi-
nant definition of vulnerability is exposure to a hazard.
The field also employs the concept of capabilities,
analogous to the concept of adaptive capacity (Schwab,
Topping, Eadie, Deyle, & Smith, 1998).
Drawing on the distinction Comerio (1998) and others
(Olshansky & Chang, in press;Quarantelli, 1999) draw
between disasters and catastrophic events, climate
change impacts that call for adaptation can be categorised
H. Blanco et al./ Progress in Planning 71 (2009) 153–205 161
4
These figures are likely to be adjusted, given more up-to-date
studies. The scientific background reports supporting the forthcoming
assessment of the US Climate Change Science programme on Coastal
Elevations and Sensitivity to Sea Level Rise were released in early
2008 (Titus & Strange, 2008).
as either disasters or catastrophic events. Catastrophic
events, as compared with disasters, involve major loss of
life and damages that test the limits of a region’s or
nation’s response capacity. Based on this distinction, we
argue that natural hazard mitigation planning is more
pertinent to disasters, which have been the major focus of
attention in the field. According to Olshansky and Chang
(in press) in their review of research on recovery
planning, research on catastrophic events and response to
them is a neglected area in the field calling for future
research. Research on responses to catastrophic events
thus remains pertinent to both climate change adaptation
and natural hazards mitigation. Natural hazards mitiga-
tion policies have also been reactive rather than
anticipatory, although researchers in this area have been
calling for more proactive approaches (Blanco, 2008;
Godschalk, Beatley, Berke, Brower, & Kaiser, 1999:
Chapter 1;Mileti, 1999: Chapter 2; Schwab et al., 1998).
Climate change impacts are systemic, whereas natural
hazards are episodic. Natural hazards are typically
temporally and spatially limited incidents, which leave
the overall system unchanged. Climate change has the
potential to change the system, in that the impacts are
long-range and spatially broad, either large-scale
regional or global. Natural hazards, even when they
are catastrophic, can count on the natural conditions
returning to a normal or steady state, or on a stable social
condition. Some climate change impacts will change
what is normal into disturbed conditions, which may
remain chaotic and not settle into a steady state for
decades or centuries. Climate change impacts are
projected to increase the frequency of natural hazards,
such as droughts or wildfires, which will put on trial the
traditional institutions, practices and financing on which
we count to respond to natural hazards or man-made
disasters. Another important difference is policy stance.
Although, as noted, some researchers in hazards
mitigation have called for anticipatory planning, the
field of practice is still dominated by a reactive approach
and Federal fundingprovided for anticipatory planning is
insufficient
5
(FEMA, 2007). In the case of catastrophic
climate change impacts, however, waiting until after the
effects to take actionmay prove to be too costly. Based on
these differences, the traditional focus, policy mechan-
isms, and institutions of the natural hazards field are
likely to be inadequate to address catastrophic climate
change impacts. Planning for climate change adaptations
presents a broader range of research and practice
opportunities for the profession.
2.2.4. The relation of climate change adaptation to
sustainable development
The IPCC Fourth Assessment report (IPCC, 2007b:
811–841) devotes a final chapter to the relation between
climate change and sustainability, concluding that:
Non-climatic stresses, such as poverty, or unequal
access to resources, increase vulnerability to climate
change impacts.
Adaptation and sustainable development share com-
mon goals and determinants, but sustainability
research has not incorporated adaptation concerns,
and some development activities could result in
increases in vulnerability to climate change impacts.
Reducing vulnerability to hazards will also tend to
reduce vulnerability to climate change, but it will not
be sufficient to eliminate all damages.
Climate change will result in net costs into the future,
and these costs will increase over time.
Climate change will impede a nation’s ability to
achieve sustainable development pathways.
Synergies between mitigation and adaptation are
highly likely to remain effective until 2050, but even a
combination of aggressive investment in mitigation
and adaptation measures would be overwhelmed
thereafter by climate change impacts (IPCC, 2007b:
813).
As clear from the summary above, the IPCC report
balances the opportunities for synergism with the
challenges facing the sustainable development and
climate change adaptation efforts. The concept of
sustainability is holistic, pertains to more than energy
and the emission of greenhouse gases, and encompasses
economic and social dimensions, in addition to
environmental (Kates et al., 2001). When mitigation
was the sole policy aim of climate change science, the
sustainability and climate change agenda coincided
over energy policy. In effect, the findings of climate
change science that warming of the planet is occurring,
and that it is very likely that most of the greenhouse
gases concentration is due to human activities, makes
one of the strongest cases that our development pathway
is unsustainable. Climate change findings make a key
argument for a sustainable development approach, and
reduction of greenhouse gas emissions is a prime goal of
sustainable development. Now, however, it is clear that
mitigation will not be enough, that even if we carry out
the most aggressive mitigation strategy, we will need to
H. Blanco et al. / Progress in Planning 71 (2009) 153–205162
5
The federal funding for pre-event mitigation planning and projects
in the US was US$100 million in 2007.
cope with major climate change impacts over this
century, and perhaps for longer. Attaining sustainable
ways of life in an evolving world is difficult in itself,
leading to ongoing debates on what are more
sustainable activities and at what scale. But variability
in climate change and underlying uncertainties will
compound this problem. Climate change impacts throw
into question whether sustainable development goals
may be achievable.
Since the 1990s, the concept of sustainability has
gained popularity in planning (Beatley, 1995; Camp-
bell, 1996;Krizek & Power, 1996;Wheeler, 2004), but
the profession has also perceived sustainability as ‘old
wine in a new bottle’, more new rhetoric than new
substance (APA, 1993), since many of the urban
development strategies in a sustainability agenda are
just good urban planning policies, e.g., growth manage-
ment, urban design, environmental protection. A study
by Berke and Conroy (2000) seems to confirm this. The
authors analysed comprehensive plans for 30 cities to
determine whether plans that stated their intent to
incorporate sustainable development differed from
those that did not, and they found no major differences
in the inclusion of sustainability measures between
plans that stated a sustainability intent and those that did
not. But it is clear that sustainability efforts in urban
planning have made more salient the need for efficient
use of materials and energy, for example, in the
emphasis on green building technology, or alternatives
to automobile travel, and have increased our under-
standing of the factors required to achieve sustainable
development, such as access to resources, institutions
and governance, and human capital, etc., which
coincide with the factors that influence adaptive
capacity (IPCC, 2007b: 816). While planning for
adaptation shares a risk management framework with
natural hazards mitigation, it will also benefit from the
holistic framework of sustainable development, its
environmental values and the enhanced understanding
of the factors that support both sustainable development
and planning for adaptation.
2.3. Planning for adaptation
Although economists, engineers and other scientists
have assumed the conceptual and analytical roles in the
development of climate change mitigation programmes,
there is a strong role for urban planning in implement-
ing such programmes. And since such programmes
need to be implemented at the local level, planners will
play a crucial role in establishing regulatory pro-
grammes and standards to reduce fossil fuel energy use
at the land use and building scales, as well as in the
transportation sector. Research in climate change
adaptation is still in a formative stage, has affinity
with an emerging research area in planning, i.e., natural
hazards mitigation, involves fundamentally a planning
process, and recognises the importance of climate
change adaptations in core areas of planning, land use
and infrastructure systems. As such, planning for
adaptation offers a rich arena for planning research,
and not just in the area of implementation. Thus far,
however, planning literature directly related to climate
change adaptation is very sparse. However, in 1990, Jim
Titus from the US Environmental Protection Agency,
currently a project manager for sea level rise at the
agency, wrote a seminal article in Journal of the
American Planning Association on strategies for
adapting to climate change. He argued for taking
anticipatory steps in long-term projects, setting prio-
rities, and undertaking strategic assessments, as well as
the need for research, development and education on
climate change adaptation (Titus, 1990a).
6
Since then, a
few studies have focused on a specific impact of climate
change and its implications for planning, including the
urban heat island effect, ground level ozone pollution
and climate change (Stone, 2005); adaptation of storm
water systems to increased rainfall (Waters, Watt,
Marsalek, & Anderson, 2003). In the US, this lack of
professional planning focus has not been balanced by
federal research on the impacts of climate change on
cities and the planning required. In contrast, the
European Union has begun to develop an approach to
adaptation (2007), and OECD has commissioned a
series of studies on climate change impacts on cities
(Hallegatte, Henriet, & Corfee-Morlot, 2008;Halle-
gatte & Patmore, 2008;Hunt & Watkiss, 2007;Nicholls
et al., 2008). In this section, we discuss the multiple
roles that planners can play in planning for climate
change adaptations. To demonstrate this, we use the
steps in the planning process model to organise the
following discussion.
2.3.1. Planning analysis: The science of climate
change adaptation
The first step in the planning model calls for the
analysis of a problematic situation and/or problem
identification. It is in this step of the planning process
that planners typically use scientific frameworks and
findings to analyse a problem, although planners, until
H. Blanco et al./ Progress in Planning 71 (2009) 153–205 163
6
See also Titus’s related article dealing more extensively with sea
level rise appearing in Land Use Policy (1990b).
recently, have mainly employed linear population and
economic projections to develop urban plans. Adapta-
tion planning for climate change will need to rely on an
emerging interdisciplinary scientific field, which cou-
ples human and natural systems and their interactions.
While natural hazards mitigation leaves planners as
consumers of research by geologists and other
scientists, a new science of landscape and land use
ecology is emerging, to which planners can contribute
(Alberti, 2008; Feddema et al., 2005; Liu et al., 2007;
Turner, Lambin, & Reenberg, 2007). This new research
field melds science and policy, draws on complexity
studies and systems analysis, and identifies vulnerabil-
ities and adaptive capacities.
More specifically, the emergence of this science will
be crucial in identifying the regional and local climate
change impacts necessary to initiate climate change
adaptation plans.
In order to determine the feasibility of adaptation
responses at a local or regional scale, global climate
change models need to be coupled with regional-scale
models that take into account local geomorphology,
atmospheric, land use, land cover, and infrastructure
systems. There are several regional-scale models that
incorporate geomorphology, hydrology, and land cover,
but the representation of the human dimension in earth
systems models is often too simplistic and fails to fully
represent the urban land use and infrastructure systems
and the highly heterogeneous urban land cover at the
appropriate scales for developing adaptation plans. A
major challenge in modelling land cover/climate
change and their impacts in urbanising regions is in
representing explicitly the human and biophysical
processes at a level of disaggregation that allows us
to explore the mechanisms linking human decisions and
urban patterns to environmental change (Alberti, 1999).
Traditional land cover change models are based on
average characteristics of the population, households,
and businesses as a whole, and cannot capture the fine-
scale interactions between the many agents and drivers
of land use and land cover change. Many models also
assume no relevant spatial and temporal dynamics
(Alberti & Waddell, 2000). In reality, the dynamics vary
across time and space, and have intrinsic feedbacks and
thresholds.
As part of the Puget Sound Biocomplexity Project
(NSF funded) Alberti, Morawtiz, Blewett, and Cohen
(2006) have developed a high-resolution, spatially
explicit land use/land cover change model (LCCM)
(Alberti et al., 2006;Hepinstall, Alberti, & Marzluff,
2008) that can be coupled with the Puget Sound
regional-scale models such as the Distributed Hydrol-
ogy Soil Vegetation Model (DHSVM) (Cuo, Letten-
maier, Mattheussen, Storck, & Wiley, 2008) and the
Weather and Research Forecasting (WRF) model (Mass
et al., 2003;Salathe
´, Mote, & Wiley, 2007) developed
by the UW Climate Impacts Group
7
(Snover & Miles,
submitted for publication) to yield the type of high-
resolution projections needed for determining local and
regional climate change impacts. The LCCM uses a set
of spatially explicit multinomial logit models of site-
based land cover transitions. The transition probability
equations are estimated empirically, as a function of a
set of independent variables comparing land cover data
at different points in time (presently for 1991 and 1999
in Puget Sound). Results from the implementation of
the model in the Central Puget Sound region showed
strong predictive skills when validated with indepen-
dent land use/land cover datasets (Hepinstall et al.,
2008). This is one example of emerging coupled models
that planning researchers can apply in collaboration
with atmospheric and other scientists to develop
regional-scale adaptation plans.
In addition to contributing to the science of climate
change projections specific to a region, planning
researchers can also contribute to the development of
vulnerability analyses. Fu
¨ssel and Klein (2006) trace the
evolution of vulnerability assessments in the climate
change literature from a concern with mitigation policy
to adaptation policy assessments. The questions that
such assessments address are: ‘What adaptation policies
are needed, and how can they best be developed, applied
and funded?’ (Burton, Huq, Lim, Pilifosova, &
Schipper, 2002). Unlike assessments focused on
mitigation of climate change, which rely on the
physical and biological sciences, adaptation assess-
ments focus on economic and social variables in a local
development context, are more integrative in nature,
and thus are more compatible with current planning
expertise.
2.3.2. The planning process and urban adaptation
plans
Urban planning and adaptation planning can be
conducted at various scales, at the community, system
or the project scale. The planning process for
community-wide climate change adaptations needs to
be integrative, strategic, participatory and incorporate
innovate ways to manage risk. Integrative across a wide
H. Blanco et al. / Progress in Planning 71 (2009) 153–205164
7
The UW Climate Impacts Group is one of only nine research
groups in the US that have this regional modelling capability, and not
all regions in the US can count on such regional models.
range of physical, biological and social sciences, since
climate change models, climate impacts, and vulner-
ability assessments call for such integration, as we
discussed in the section above. In planning practice, this
call for integration will require at a minimum
incorporating shoreline, watershed and land use and
infrastructure planning, including energy planning. To
illustrate the need for integrative planning, let us focus
on the impacts of sea level rise on coastal areas. In
addition to inundations, these impacts include more
frequent or intense storm surges, greater flooding
potential, and droughts, which will require compre-
hensive and effective regional land and water resource
management along the coastal regions. The Coastal
Zone Management Act (CZMA) of 1972, as amended,
is the key federal legislation to address coastal issues in
a comprehensive, integrated way, recognising state and
local roles in addressing coastal issues. CZMA provides
incentives and funding for the preparation and
implementation of state/local shoreline master plans.
Shoreline master plans are major tools for managing
extreme coastal region conditions, but these plans are
often inconsistent with local land use plans, except in
states where consistency between plans is required.
Watershed planning is the other major mechanism
which many states and local governments use to
manage the quality and quantity of their water resources
within drainage areas or watersheds. The preparation of
such plans is recommended by EPA in the case of
‘impaired’ water bodies—water bodies that do not meet
the criteria for their designated use. Watershed plans are
often not integrated or consistent with local land use
plans, and fail to protect water resources. Adaptation
planning thus challenges planning to fulfill its promise
of comprehensiveness.
Many cities today have incorporated climate change
mitigation measures in their urban plans. These are
typically part of a broader sustainable development
agenda. For example, the City of Seattle has adopted
LEED (a green building rating system) principles in the
construction of its public buildings and in its downtown
density bonus regulations. Local governments have
been slower to respond to adaptation planning. In this
respect, King County in Washington State has shown
exceptional leadership in developing a county climate
plan that incorporates both mitigation and adaptation
measures (King County, 2007; Swope, 2007). Based on
the impacts projections of the University of Washing-
ton’s Climate Impacts Group for the Puget Sound, King
County has developed a set of guidelines for
incorporating mitigation and adaptation goals into
county and city agencies, has identified a set of urgent
adaptation needs, for example, specific water supply
pipelines or county roads within or close by floodplains,
and is taking steps to improve its capacity to undertake
adaptation planning by, for example, entering into a
collaborative agreement with the Climate Impacts
Group, educating appropriate county staff in climate
change science, and raising public awareness on this
issue. Although the plan does not include specific
implementation steps, its goal of incorporating climate
change adaptation considerations in all relevant county
plans and projects is farsighted. The incorporation of
climate change adaptation concerns in existing guide-
lines or review processes is referred to as ‘mainstream-
ing’, in contrast to efforts to create new processes.
Mainstreaming climate change concerns is widely
advocated to ensure that such concerns ‘become part of
or will be consistent with other well-established
programmes, particularly sustainable development
planning’ (IPCC, 2007b: 732).
8
On the other side of the country, NYC’s new plan,
PlaNYC 2030 (2007) is an early model of an integrated,
strategic plan that incorporates both mitigation and
adaptation strategies to climate change and addresses
energy, sea level rise and water resources. Again,
NYC’s plan benefited from sophisticated regional
modelling of the greater New York region. It relied
on the Metropolitan East Coast (MEC) Assessment for
the New York region (Rosenzweig & Solecki, 2001)
that was prepared as part of US EPA’s National
Assessment of Climate Change in the United States
(National Assessment Synthesis Team, 2001). The
MEC was the only of the 18 US regional assessments
that was primarily focused on urban issues. In addition,
MEC researchers continued to deepen their work on the
impacts of climate change in the NY region, including
adaptation assessments of the heat island effect (Solecki
et al., 2005), heat-wave and ozone-induced health
impacts (Kinney et al., 2007), as well as water supply,
sewer and wastewater treatment (Rosenzweig et al.,
2007). The Climate’s Long-term Impacts on Metro
Boston (CLIMB) project modelled the impacts of
climate change on the metropolitan area’s transporta-
tion, water resources, coastal and riverine flooding,
energy and health, and conducted a cost-effectiveness
analysis of three response scenarios, including no action
H. Blanco et al./ Progress in Planning 71 (2009) 153–205 165
8
The King County Climate Plan also emphasises the value of ‘no
regrets’ measures. A no regrets climate change adaptation is meant to
provide benefits to communities whether anticipated climate change
occurs or not, e.g., water conservation and demand management
measures.
and early action responses (Kirshen et al., 2004;
Kirshen, Ruth, & Anderson, 2008).
In Europe and world-wide, the city of London is a
clear leader in planning for adaptation. Its efforts also
began as part of a national programme, the UK Climate
Impacts programme, geared to promote and coordinate
research on impacts of climate change, which led to the
formation of the London Climate Change Partnership
(LCCP) (Penney & Wieditz, 2007). The Partnership,
with great support from Mayor Livingstone, developed
downscaling models to generate regional scenarios, and
identified options and institutional strategies for
temperature increases, flood risks, and water avail-
ability (LCCP, 2002, 2005, 2006). In Canada, the Clean
Air Partnership (CAP) has undertaken a climate change
adaptation programme for Toronto in partnership with
the City. In addition to stakeholder workshops, CAP
prepared a scan of climate change impacts for the city
(Wieditz & Penney, 2006), a study of six major cities’
climate change adaptation efforts (Penney & Wieditz,
2007), and a set of options for two areas, the urban
forest (Wieditz & Penney, 2007a), and heat, including
heat’s impacts on health and energy use (Wieditz &
Penney, 2007b).
In addition to individual cities’ efforts, the IPCC and
the literature on vulnerability to climate change have
emphasised the importance of stakeholder involvement
(Burton et al., 2002; IPCC, 2007b: 141–142) in the
planning process, an emphasis consonant with the
participatory ethos of planning. Adapting to climate
change has irreducible uncertainties, requiring innova-
tive ways to manage risk. Some innovative responses that
incorporate strong participatory processes have been
developed andare beginning to be applied, e.g., scenario-
based and stakeholder involvement approaches, such
as that developed by the Urban Ecology Lab at UW
(Alberti & Russo, in press) and applied to the Pacific
Northwest, as well as the robust decision-making
approach developed by RAND researchers (Lempert,
Groves, Popper, & Bankes, 2006) and recently applied to
water resources in California.
In contrast to community-wide planning, planning for
climate change adaptation can also be conducted from a
functional or sectoral perspective. Transportation,
energy, public health, and water infrastructure planners
can play significant roles in developing such plans.
Several countries, and some regions, are beginning to
prepare vulnerability assessments or climate change
plans for infrastructure systems. For example, the
government of Canada has published a nationwide
report on climate change impacts and challenges
(Lemmen and Warren, 2004a, 2004b) and a subsequent
2006 literature review described efforts across Canada to
assess the vulnerability of infrastructure systems to
climate change impacts and adaptation efforts (Infra-
structure Canada, 2006). In addition, Waters et al. (2003)
examined the impact of increased rainfall due to climate
change on typical urban catchments in southern Ontario,
Canada, and identified adaptive measures. The Climate’s
Long-Term Impact on New Zealand’s Infrastructure
(CLINZI) project is a research project which has begun
applying a quantitative model to the infrastructure
systems in several cities in New Zealand to determine
their vulnerability to climate change impacts (Jollands,
Ruth, Bernier, & Gloubieswki, 2007). Water resources,
especially in the western US, where precipitation
changes due to climate change will have significant
impacts, have been the subject of several studies,
including Tanaka et al.’s (2006) study of California’s
water systems, Mote et al.’s (2003) study of the impacts of
climate change on the Pacific Northwest’s water
resources and ecosystems, Payne, Wood, and Hamlet’s
study of the Columbia River basin (2004), and
Frederick’s (1997) broader study on water supply and
demand. The California Energy Commission has
developed scenarios of climate change impacts in
California for several sectors, including natural
resources, ecosystems, infrastructure, health systems
and the economy (Cayan et al., 2006; Hayhoe et al.,
2004), as well as studies on the impact of climate change
on extreme heat and energy demand (Miller, Jin,
Hayhoe, & Auffhammer, 2007).
With respect to the impacts of climate change on
transportation systems, the US Department of Trans-
portation (DOT) held an important research workshop
on the potential impacts of climate change on
transportation (USDOT, 2002), which generated case
studies of climate impacts on the transportation systems
in the New York Metropolitan Area, the Gulf Coast/
Mississippi Delta Region, the Great Lakes, California,
Alaska, and the Atlantic Coast. Many of these case
studies focused on sea level rise and increased flooding
impacts. Since then, US DOT has commissioned two
major studies, currently under way:
(a) A consultant study of how sea level rise and storm
surges could affect transportation infrastructure on
the East Coast (ICF International, 2007). The first
phase of the study identifies impacts on highways
and arterials in North Carolina, Virginia, Washing-
ton DC, and Maryland, and the second phase will
address impacts in New York, New Jersey,
Pennsylvania, Delaware, South Carolina, Georgia,
and the Atlantic Coast of Florida.
H. Blanco et al. / Progress in Planning 71 (2009) 153–205166
(b) A study of the impacts of climate change and
variability on transportation systems and infra-
structure focusing on the Gulf Coast (US Climate
Change Science Program, 2008). In addition to sea
level rise, the impacts of warming effects on
permafrost and their effects on transportation have
been subjects of concern in Canada and Alaska
(Infrastructure Canada, 2006).
Planning for climate change adaptations in infra-
structure systems can also be accomplished at the
project level. A few such cases have been documented,
including the Deer Island sewage treatment plant in
Boston. In this case, the location of a sewage treatment
plant was changed to a higher elevation to take into
account projected climate change impacts. The original
site was for a lower elevation, but projected sea level
rise would have required a wall around the original site
proposed for the treatment plant and this would have
required expensive pumping to surmount such a wall
(Easterling, Hurd, & Smith, 2004). In addition,
communities can ensure that adaptation concerns are
addressed in the design of individual infrastructure
projects, by incorporating or mainstreaming such
concerns in guidelines for project development, such
as King County in Washington State is requiring of
county projects (King County, 2007).
2.3.3. Identifying and designing strategies
At the stage of identifying alternative strategies in
the planning process, a whole array of strategies can be
identified and developed for various climate change
impacts. For example, for sea level rise, three broad
types of strategies have been identified: protection
strategies, aimed at protecting land from the sea so that
existing uses can continue by constructing hard
structures (e.g., seawalls) or using soft measures (beach
nourishment); accommodation strategies, whereby
people continue to occupy the land, but make some
adjustments, such as elevating buildings on piles; and
retreat or abandonment strategies, where there is no
attempt to protect land from the rising sea (Bijlsma
et al., 1996). Identifying strategies also entails an
analytic process to unpack the features of alternative
strategies.
Continuing with our example of sea level rise
strategies: if protection measures, such as dikes and
levees, are an option, to what specification should a
dike or levee be developed? To the last storm, to
predicted sea level rise by mid-century, to the sea level
riseprojectedbytheendofthecentury?But
determining the specifications of a levee to adapt to
climate change impacts is further complicated by the
variability inherent in climate change impacts and the
likelihood of extreme events. Also, protection schemes
such as levees or dikes may further disturb ecosystems,
such as marshes or wetlands, which may pose their
own detrimental consequences. In identifying strate-
gies, in addition, planners must consider their
financing. Typically, levees are public projects and
publicly financed. Who will bear the costs and through
what fiscal mechanisms? Should a special tax or
property tax be used? Fiscal means have different
distributional impacts that should be considered.
Also, what will be the effects of such measures on
migration? And then there is the issue of timing such
an adaptation, should a levee be constructed after a
major flood event or before?
If we consider strategies of accommodation to sea
level rise, such as requiring the raising of structures,
such strategies may involve changing building codes
and zoning to require building on piles in certain
areas, as well as raising roads and other infrastruc-
tures. How high should the structures be raised, to what
specification? When we consider building code
changes which apply to new construction, how can
we ensure that existing buildings meet the new codes?
In this case, some of the costs of the adaptation
strategies, e.g., the cost of raising buildings or private
utilities, will be private, others public, such as the
costs involved in raising government structures,
including roads and other infrastructure. How should
the revenues to pay for the public costs be raised,
through special districts? What about poorer indivi-
duals or communities who could not afford such
improvements? What arrangements should be made
for them? Also, as with protection strategies, acco-
mmodations strategies could fail to protect in the case
of extreme events.
Managed retreat strategies for sea level rise, such as
density restrictions in areas impacted by sea level rise,
would provide more protection, but would involve
property rights issues, and would probably require
public land acquisition or easements (Titus, 1998)at
varying costs. At the far end of retreat strategies, a
community might consider abandonment of areas
threatened with inundation. Such an approach might
involve deconstruction of existing settlements and
development of new settlements in less vulnerable
areas, and require strengthened redevelopment powers
to condemn and deconstruct existing development and
compensate individuals, to plan and relocate the
community out of harm’s way, and to finance the plan
and relocation.
H. Blanco et al./ Progress in Planning 71 (2009) 153–205 167
2.3.4. Assessing strategies
Adaptation strategies need to be evaluated. How
should this be done? What are the strengths and
weaknesses of traditional assessment methods, such as
cost–benefit analysis, cost-effectiveness, or multi-
criteria evaluation, when applied to climate change
strategies? The Stern Review (2006), an influential
economic evaluation of mitigation and adaptation
efforts conducted for the British government, uses a
cost–benefit analysis approach, but has been widely
criticised for various reasons, among them the discount
rate used, but a compendium of evaluation tools has
been identified by the United Nations Framework
Convention on Climate Change (Stratus Consulting
Inc., 1999). A recent OECD report (Hallegatte, Henriet,
et al., 2008) develops a conceptual framework for
assessing costs and benefits at the city scale. Building
on the growing interest for adaptation planning at the
city scale, the report outlines a process of economic
evaluation which incorporates downscaling socio-
economic scenarios as well as climate predictions.
Whatever type of method is used to evaluate strategies,
methods need to incorporate criteria that take into
account interdependencies, e.g., how seawalls will
affect marshlands, as well as distributional impacts,
e.g., how will the strategies affect poor or elderly
people?
Another significant aspect of evaluation is the extent
of public participation and support for the selected
strategies. Many evaluation methods, including cost–
benefit analysis, however, are highly technical, obtain
little public input, and because of their technical nature
do not get wide public attention. This is why
stakeholder or participatory scenario-based forums,
which incorporate the evaluation of strategies by large
groups of stakeholders, hold such promise. In addition,
participatory processes could also include technical
evaluation techniques, as long as the participants are
educated in the assumptions, mechanics and inputs used
in such methods. Such evaluations will be required for
expensive climate change adaptation measures, and
many planning researchers are equipped to undertake
such studies.
2.3.5. Implementation issues
The AR4 report emphasised the importance of
further research on ‘the practical, institutional, and
technical obstacles to the implementation of adaptation
strategies’ (IPCC, 2007b: 804) to improve our under-
standing of adaptation and adaptive capacity. It
indicates that we require ‘a richer characterization of
the perception–evaluation–response process at various
levels and scales of decision making, from individuals
to households, communities and nations’ (p. 804). In
general, implementation issues plague the best of plans.
In this section, we explore three key implementation
issues for climate change adaptation plans: institutional,
financial, and legal.
2.3.5.1. Institutional. Institutional designs and prac-
tices can clearly decrease or increase exposure to
climate risks. Identifying the institutional mechanisms
that can be used for planning and implementing
adaptation strategies is an important task. In most
cases, these would be existing institutions in charge of
planning, water resources, transportation and other
relevant agencies. Existing institutions may need to
adapt themselves to confront climate adaptation issues.
Many public institutions are not very innovative,
functioning on standard operating procedures. How
can organisational learning be facilitated in these
institutions? Since understanding of climate change
impacts is relatively new, and particular to a region,
institutions first need to learn how these issues will
impact the services that they provide. King County’s
outstanding efforts on climate change focus on the issue
of institutional learning first. Their climate plan aligns
the County government with experts in climate science
to facilitate this understanding, designates specific staff
to become experts in these issues, and sets up processes
for staff in various county agencies to learn and
incorporate climate change concerns in their activities.
Without such institutional learning, institutional inertia
is likely to become a prime obstacle to climate change
adaptations (Berkhout, Hertin, & Gann, 2006). But
some adaptive responses may call for new agencies.
Today, the Corps of Engineers is in charge of the
relocation of the dozens of villages in northwest Alaska
threatened by sea level rise and erosion from storm
surges, but the Corps, an institution based on a
command and control structure, may not be the
appropriate agency for leading community decisions
that require a participatory approach. What kind of
institutional design would facilitate the task of
relocating and developing new settlements for com-
munities threatened by extreme climate change
impacts?
In addition, since climate change impacts on cities
will require an integrated approach to planning, how
can adaptation planning address the existing frag-
mentation of planning and regulatory mechanisms
within cities, where the various urban systems are
typically planned and operated by different local
agencies, and when the modern metropolis is
H. Blanco et al. / Progress in Planning 71 (2009) 153–205168
fragmented into multiple government jurisdictions,
lacking effective metropolitan governance structures?
2.3.5.2. Financial. Research on the fiscal mechanisms
for implementing adaptation options, especially some of
the protection or retreat options, is needed. What types of
fiscal mechanisms could generate funds in a futurewhere
energy prices will probably be higher, and in a context
where there is an existing deficit in maintaining the
infrastructure that we now have. Currently, the American
Society of Civil Engineers (ASCE, 2005) estimates that
we need to invest US$1.6 trillion in infrastructure
systems over the next five years to bring the systems into
good order. One major impact of climate change will be
greater precipitation in many parts of the country, which
is likely to result in more flooding in many places at high
and mid latitudes. In many cities, sewage systems are
combined, which is likely to mean more combined sewer
overflows (CSO) events, and a heightened need to
separate sanitary from storm drainage systems, as well as
a need to expand capacity for storm drainage systems.
This would add to the US$1.6 trillion figure. In order to
address the magnitude of these investments, do we need a
national capital budget such as the ASCE callsfor? States
and cities typically have budget stabilisation or rainy day
funds that provide short-term fiscal cushions. More
recently, state and local governments have been
exploring emergency trust funds (stormy day funds)
(Gullo, 1998). The cost of land acquisition or infra-
structure improvements called for by adaptation plans
could be financed by a similar type of trust fund. Such a
fund could be generated, for example, by a surcharge on
property insurance programmes. In addition to govern-
ment fiscal tools, planning researchers could also address
the roles of insurance and markets in adaptation plans
(Ward, Herweijer, Patmore, & Muir-Wood, 2008).
2.3.5.3. Legal. The expanded use of regulatory tools
to adapt to climate change is advocated in the IPCC
assessments. Urban planners are the experts in the use
of land use planning tools, but the expanded use of
such tools, for example, the expansion of protected
areas due to changes in floodplains or sea level rise,
may be contested in courts, given the current legal
climate, especially in the US Supreme Court. There is
also the issue of how to deal with existing land uses in
areas that are vulnerable to climate change impacts.
Adaptation measures will require more vigorous use of
planning and regulatory powers, but in order to exercise
these public powers, legal issues related to the
interpretation of police power, the public trust doctrine,
and takings may also need to be addressed.
9
In effect,
adaptation is likely to require strengthened police and
public trust powers at a time when the creative tension
between individual property rights and public powers
are tilted in the courts towards property rights. What
kind of legal mechanisms or reasoning could be useful
to bring about a more appropriate balance at a time
when we face adaptation challenges?
2.4. Conclusion: Opportunities for the profession
Climate change will be increasingly experienced
over the 21st century. Societies throughout the world
will either choose to wait and react to climate impacts,
or plan ahead to adapt to changing conditions. The
planning profession can play a vital role in every aspect
of adaptation planning, including:
Contributing to the emerging science with land use
and land cover at its centre.
Entering into collaborative research with climate
science experts to develop regional climate impact
models.
Designing and facilitating community and stake-
holder participatory processes to develop the political
will to make planning choices.
Identifying and developing alternative adaptation
strategies.
Evaluating adaptation strategies.
Contributing research and solutions to the imple-
mentation challenges ahead.
As a profession dedicated to the public interest, in
developing a research agenda for climate change
adaptation, we can lead our communities to plan and act
on two fronts: mitigation to avoid the worst possible
scenarios in the long run, and adaptation to respond
to already apparent and projected climate change
impacts.
H. Blanco et al./ Progress in Planning 71 (2009) 153–205 169
9
See Titus (1998) for a promising regulatory mechanism, ‘rolling
easements’, which are meant to address both property rights concerns
and climate impacts. But success of rolling easements depends on
stable changes in sea level rise and fails to deal with the issue of
climate variability.
Chapter 3. Non-motorised travel research and
contemporary planning initiatives
Ann Forsyth, Kevin J. Krizek and Daniel A.
Rodrı
´guez
10
3.1. Introduction
As nations and communities across the globe
wrestle with traffic congestion, depleting non-
renewable resources, the threat of global warming,
increasing obesity, and decreasing quality of life, the
automobile is often targetedasaprimaryculpritfor
such problems. Disciplines from public health to
architecture, sociology to civil engineering are re-
evaluating the means by which people transport
themselves, not just within central cities but also in
suburban areas and beyond. Such discussions have
increasingly turned to non-motorised travel (hereafter
NMT), particularly walking and cycling, as a means
to address myriad issues.
Despite a growing body of literature touting the
merits of NMT, researching their determinants, and
conjecturing about secondary benefits, much remains
unknown. What individual and environmental factors
spur increased use of these two travel modes? Are the
factors similar or different? To what extent? Under
what circumstances? What policy concerns can
increased walking and bicycling help remedy? Where
are their empty promises? Overall, the enthusiasm
generated over NMT has created a need for evidence on
the degree to which different policies have succeeded in
inducing walking and cycling travel and producing
other benefits for the community.
This chapter identifies the increasing research and
policy relevance of NMT for the general population,
determines gaps in the evidence, discusses planning
implications, and helps set an agenda for future
research. This chapter has three parts: (a) explaining
why walking and/or cycling are rising in prominence
among urban planning issues; (b) distinguishing
between walking and cycling; and (c) identifying
research opportunities from the current knowledge base
while outlining how research on non-motorised issues
could best be positioned in the future. The issue of
liveability, while difficult to define, is probably the most
robust justification for increasing use of, and research
on, NMT.
3.2. Rise and prominence of walking and cycling
issues
Research and attention to NMT is burgeoning, with
widely varying motivations (see Table 1). Some
professions and disciplines (e.g., traffic engineers) have
had long interest in looking at these matters; others are
relative newcomers (e.g., public health). Some profes-
sions see NMT as creating problems; for example,
safety conflicts between motorists, cyclists and pedes-
trians. Others, such as environmentalists and public
health officials, see NMT as a solution. Still others see
NMT as representing a desirable state of affairs,
embodying vibrancy and vitality in city streets. For
many, NMT is a means to reach a set of ends, some
unsupported or weakly supported by research; these
ends range from reducing car use and non-renewable
energy consumption to increasing social cohesion and
population health.
In addition to those described in Table 1, other
groups include landscape architects; parks and recrea-
tion planners; educators; activists; local politicians; and
decision-makers who champion NMT. For example,
trail advocates aim to increase off-street networks,
primarily for cycling. While recreation was an early
focus of trail advocates, funding priorities from
departments of transportation and a desire to meet
the needs of low-income populations has meant
increased emphasis on trails that serve travel purposes.
Advocates and other neighbourhood groups interested
in traffic calming and other street designs that promote
liveability, such as complete or shared streets, view
NMT as a central building block for the success of such
initiatives.
We identify four predominant motivations for pro-
moting NMT—congestion, environmental conservation,
health and liveability. They provide the focus for much
current professional and activist concern about NMT, and
explain the increasing attention that the topic is
garnering. We address each motivation below, recapping
its relationship with NMT, how NMT is slated to help,
and the limitations of NMT to effectively or comprehen-
sively address issues within this policy area.
3.2.1. Traffic congestion
In most, if not all, urban areas traffic congestion is
perceived by residents and businesses as a problem.
Although an often glossed over benefit of vehicular
congestion is urban vibrancy and vitality (Taylor, 2002),
concerns about productivity losses and harmful emis-
sions that ensue are paramount. From London to Lagos,
residents of cities lament traffic volumes, the accom-
H. Blanco et al. / Progress in Planning 71 (2009) 153–205170
10
Authors are listed alphabetically; each contributed equally.
panying noise from cars and trucks, and the attendant
environmental effects (examined below under environ-
mental conservation). The time spent in traffic
congestion is often viewed as wasteful; in the US it
is a barometer the Texas Transportation Institute
measures in its annual mobility report (Schrank &
Lomax, 2006). Rapid increases in vehicle ownership in
many cities in Asia or India (Dimitriou, 2006;
Gakenheimer, 1999;Pucher, Peng, Mittal, Zhu, &
Korattyswaroopam, 2007;Sperling & Clausen, 2002)
accompanied by the emerging interests of industrial
conglomerates in producing a truly popular car that will
result in mass motorisation, promise to keep vehicular
congestion as a primary motivator for NMT research.
A primary argument in favour of NMT over cars
relates to space. A normal-sized car with a single
passenger (the driver) consumes, on average, 107 ft
2
while static (assume the auto is 16.5 ft long and 6.5 ft
wide). A static bicycle requires 15 ft
2
(5 ft 3 ft). Fruin
(1971) suggests a static pedestrian requires 3.2 ft
2
(1.64 ft 2 ft). These dimensions increase once set in
motion (i.e., moving cars require braking distance, etc.),
H. Blanco et al./ Progress in Planning 71 (2009) 153–205 171
Table 1
Interest in NMT, by profession/discipline.
Group Concern(s) Predominant prescription Key references
Traffic engineering Focused on improving vehicular flow,
measured in terms of speeds, delay and
level of service, while attaining safety
standards. Mixing travel modes is often
seen as confusing and unsafe, with
pedestrians and/or cyclists competing
for the same travel space with cars
(although there is increasing concern
about pedestrians and cyclists
competing for similar thoroughfares)
Separate facilities for different
modes of travel
Forester (1982, 2001)
and Pucher (2001)
City planning Seen as a way to address congestion
and liveability. Increasingly aware of
urban development actions and local
policies that can support or hinder NMT.
Emerging interest in bicycles, as these
require more specific infrastructure than
pedestrians and in the hazard-related
evacuations for those without cars
More compact urban form, bringing
origins and destinations closer
together, ‘complete streets’, but
sometimes separate facilities for
different modes
Popular in Europe and
Australia as a planning
goal; see review of
British policies
(Williams, 1999); and
Dutch policies
(Schwanen, Dijst, &
Dieleman, 2004)
Urban design Interested in street life. People walking
along the streets are key to creating
vibrant public areas at a human scale.
Little concern with cycling
Eyes on the street to create vibrancy
and vitality. Aesthetics is also key
Lynch (1962),
Appleyard and Lintell
(1972),Alexander et al.
(1977),Appleyard (1981),
Lynch (1981),Gehl (1987),
Whyte (1988),Jacobs
(1993),Southworth and
Ben-Joseph (1997)
Environmental
studies and
advocacy
Concerned with the environmental
impacts and sustainability of
contemporary urban areas and
prevailing travel patterns
NMT can be make cities more
sustainable by achieving reductions
in the use of non-renewable energy
sources, carbon emissions,
impervious surface cover, while
improving air quality
Campbell (1996),
Newman and Kenworthy
(1999),Beatley (2000),
Berke, Godschalk,
Kaiser, and Rodrı
´guez
(2006) and Wolch (2007)
Public health Interested in environments supportive
of healthy lifestyles (mostly physical
activity and access to healthy foods)
and potential for environments to
address health concerns. Somewhat
interested in physical access to
health-related destinations,
particularly for those without cars
Providing for built environments
supportive of walking and cycling,
ranging from mixed use to mode
specific infrastructure. Also
include educational/programming
campaigns
Handy et al. (2002),
Frank, Engelke, and
Schmid (2003) and
Frumkin, Frank, and
Jackson (2004)
dramatically so for higher speeds. Given limited space
for movement (e.g., a road) cars require the most space.
Fitting too many cars into too little space results in
traffic congestion. Walking and bicycling therefore fit
many more travellers into available space and result in
less overall congestion, at least for autos.
Given auto driving, there are several technical and
pricing policies to address auto congestion concerns.
People could use smaller cars, policies could restrict car
use during certain peak hours, as in Bogota
´and Mexico
City, intelligent transportation systems could space cars
better or provide timely information to travellers, or
pricing could moderate congestion, as in London or
Singapore. However, some propose alleviating auto
congestion by diverting short trips from autos to transit,
walking and bicycling.
The auto is so extensively used because of the
convenience it provides for relatively long travel
distances; the average length for a trip in the US is
10 miles (Hu, 2005). Prevalent urban development
patterns, with increasingly distant origins and destina-
tions, require motorised modes. Long trips tend to be
related to work purposes and therefore occur during few
hours of the day (the a.m. and p.m. peak periods) and
must rely on limited road facilities. Short trips, such as
shopping and school-related trips, rely more on
neighbourhood streets, with usually less congestion.
Bringing origins and destinations closer together by
increasing density or mixing land uses may help spur
NMT (Apogee Research, 1998;Ewing, Pendall, & Chen,
2003). However, the efficacy of land-based strategies to
address auto use and congestion has its sceptics (Downs,
1999). Empirically, fairly large increases in density
would be required to observe decreases in trip lengths
(Giuliano, 1995;Ewing, Pendall, et al., 2003;Schimek,
1996), while others have suggested that trip distances
(Levinson & Kumar, 1997) and VMTs (vehicle miles
travelled) may increase with density (Rodrı
´guez, Targa,
& Aytur, 2006). As a result, travel modes that can better
cater to longer trips should receive more attention than
those serving short trips for congestion relief. Bus and rail
transit are natural front-runners, but cycling could
compete in some markets. Improving access to transit
by non-car modes can be a promising strategy to shift
long trips from automobiles to mass transportation, while
decreasing some of the auto’s deleterious impacts. Under
such reasoning, NMT’s contribution to congestion relief
appears most promising when viewed as an enabler for
other transportation modes.
Claims that significant modal shifts can reduce
congestion assume that people who would normally be
driving would switch to NMT. Vehicular travel currently
comprises 89% of all trips in the US, walking 8%, and
cycling a mere 0.8% (Hu, 2005). Doubling the number of
NMT trips—a dramatic increase—means that almost a
combined 20% of all trips would be by walking or
cycling. The differences that would be noticeable from
such a change would most likely be detected in parking
requirements (again, bicycles require much less space for
storage and pedestrians require no storage), and probably
would not be detected in congestion reduction. Thus,
advocates who tout the merits of providing for NMT as a
means to address congestion face a difficult challenge,
given the magnitude of the change that would be required
to produce substantial improvements.
3.2.2. Environmental conservation
While congestion creates productivity costs and
may be a daily irritation for many, a variety of
environmental problems also stems from excessive
motorisation. Most vehicles still rely on fossil fuels.
These have well-known costs, including localised air
pollution, contributions to global warming, and a role
in promoting geopolitical strife. While electric cars,
hybrids and even vehicles relying on bio-diesel are
growing in numbers, they still use carbon-based
sources of energy. However, the environmental effects
of motorisation in Asian and other developing cities
suggest that impacts of auto use will also be a motivator
for NMT research and policy.
A major move back to non-motorised modes, some
propose, would circumvent emerging environmental
problems. A classic article by Lowe in 1989 highlighted
the bicycle’s advantages in decreasing the overall
footprint for transportation-related services (Lowe,
1989). Such ideas, namely that NMT epitomises
environmentally benign travel, have been most popu-
larised within the urban planning literature by Newman
and Kenworthy (1989, 1992), correlating energy use
and density for 30 cities around the globe. Similar
relationships have been identified elsewhere (Banister,
Watson, & Wood, 1997;Rickaby, 1987). This research
highlights the link between urban form (namely
density) and consumption of natural resources, thereby
suggesting a role for NMT in environmental conserva-
tion.
11
Many claim such dense cities can be sustainable
or green cities (Beatley, 2000).
H. Blanco et al. / Progress in Planning 71 (2009) 153–205172
11
It is important to mention that the Newman and Kenworthy work
provoked many critics and subsequent questions. A cursory glance at
tables shows that cities with similar densities have vastly different
energy use and there are obviously many factors at play apart from
city form—policy, pricing, culture (Gordon & Richardson, 1989).
The high-density, low-energy, NMT-supportive city
is not the only vision of the green city. Dating back to
the 19th century suburban developments and the work
of Ebenezer Howard, some have proposed a lower
density, visibly greener version that is more spread out.
This allows other environmental and social benefits,
such as water infiltration and access to nearby nature
(Calthorpe, 1993;Calthorpe & Fulton, 2001;Hall &
Ward, 1998). This is the vision favoured in some urban
development circles, and by professions such as
landscape architecture (Arendt, 1994, 1999). In the
more polycentric and compact ‘garden city’ version of
this approach, walking and cycling are modes that
support trips for daily sustenance like shopping and
recreation within each node of development. Adequate
transit access is needed to connect nodes.
Urban patterns alone, however, do not appear to be
enough to change behaviour to achieve a sustainable
city. Reaching such environmental sustainability
requires a combination of changes—ranging from
urban form, to pricing and cultural expectations. Spatial
structures of a given city matter, but so do relationships
across cities. Consumption and production nodes now
have global links, requiring freight transportation and
long distance journeys dependent on fossil fuels, and
that cannot be substituted by NMT modes. These intra-
city and inter-city relationships raise questions about
the feasibility and complexity of the sustainable city.
3.2.3. Health
A major impetus for NMT over the past half dozen
years has come from the field of public health, in efforts
to address decreases in physical activity and con-
comitant increases in obesity, cardiovascular disease
and diabetes. An individual’s weight is a function of
energy consumed in food minus energy expended in
physical activity. The increase in weight may therefore
be due to an increase in energy intake (food), a decrease
in energy expenditure (physical activity), or some
combination of the two. While weight is a factor in a
number of diseases, such as coronary heart disease and
diabetes, physical activity is independently associated
with these and other health problems (Spanier &
Marshall, 2006;Warburton, Nichol, & Bredin, 2006).
Increased use of NMT could be part of the solution to
counteract people’s sedentary behaviour—some think a
major part. Both forms of NMT require human
propulsion, which help address matters of human
energy balance.
A predominant hypothesis at the onset of recent
health-related research was that a decrease in walking for
utilitarian purposes (both the commute to work and other
routine walking) was a major culprit for observed
increase in weight (Ewing, Schmid, Killingsworth, Zlot,
& Raudenbush, 2003). Bicycling was not seen as
important, because of the low numbers of cyclists
relative towalkers. If true, the policy solutions that would
result were obvious. However, lacking reliable long-
itudinal data on physical activity as a whole, or walking
and cycling—with the exception of the commute to
work—it is difficult to examine this hypothesis.
A number of studies have, however, shown that
walking for transportation seemed to be higher in
locations with higher densities, mixed uses, connected
street patterns and supportive pedestrian-oriented
design features (Cervero & Kockelman, 1997;Frank
& Pivo, 1994;Handy, 2005;Saelens, Sallis, & Frank,
2003;Steiner, 1994; Transportation Research Board,
2005). The focus of this research was a carrots
approach, making the built environment more suppor-
tive of walking. By contrast, urban planners point out
that making motorised travel more expensive and
difficult could also be an effective way to shift travel to
non-motorised modes—a sticks approach. Other studies
have found that making parking difficult or having no
access to cars can increase transportation walking or
moderate physical activity (Dombois, Braun-Fahrla
˜n-
der, & Martin-Diener, 2007;Forsyth, Oakes, Schmitz,
& Hearst, 2007;Rodrı
´guez, Khattak, & Evenson, 2006).
Furthermore, the evidence suggests that some environ-
ments also support walking for recreation, but these
tend to be different from the environments that support
walking for transportation (Forsyth et al., 2007; Giles-
Corti et al., 2005;Hoehner, Ramirez, Elliott, Handy, &
Brownson, 2005;Lee & Moudon, 2006;Rodrı
´guez,
Khattak, et al., 2006). A small amount of work has
examined whether different kinds of people—e.g., the
healthy, those with children, different ethnic groups—
walk more in specific areas, but results are mixed and
more study is needed (Forsyth et al., 2009). Discerning
how different environments play roles of varying
importance as supports and barriers of various types
of walking is a promising line of research.
The growing debate is about how much of the higher
rates of walking observed can be attributable to the
environment itself, or to the selection of people who like
using NMT in environments that provide some support,
so that the environmental effect is magnified by
personal preferences, termed self-selection (Krizek,
2003a, 2003b;Cao, Handy, & Mokhtarian, 2006;
Handy, Boarnet, Ewing, & Killingsworth, 2002). To
some extent, this sorting by environmental preferences
is precisely what planners would like to achieve,
particularly in areas where environments that support
H. Blanco et al./ Progress in Planning 71 (2009) 153–205 173
walking are lacking, due to planning constraints.
However, the importance of isolating the impact of
residential sorting on observed walking behaviours
from the environmental impact itself is still important. If
findings of people walking more in certain places are
mostly due to their preferences and self-selection, and
there are enough environments that such people find
supportive to fulfil their needs, then creating more such
environments will probably have little effect.
Beyond walking, the more ambiguous findings stem
from studies assessing NMT in relation to overall
physical activity.
12
One reason is that outdoor walking
makes up perhaps 15–20% of physical activity (Forsyth
et al., 2007). Another reason is that individuals can
substitute physical activity in one location for physical
activity in another location, depending on the presence
or absence of walking supports (Krizek, Birnbaum, &
Levinson, 2004;Rodrı
´guez, Khattak, et al., 2006).
3.2.4. Liveability
Congestion, traffic jams, car costs, air pollution, ugly
freeways and bare parking lots waste time and money,
cause daily irritations, and limit the pleasures of living
in cities. In suburban environments, many lament the
need to get in the car for simple errands. Parents’ need to
chauffeur children between activities is seen as a
burden; the lack of face-to-face interaction and
subsequent decline in social capital has been mentioned
as a drawback of the lack of NMT as well (Duany,
Plater-Zyberk, & Speck, 2000).
In contrast, the ‘success’ storyinalmostallcity
planning initiatives is a ‘walkable’ area, with an array
of shops, perhaps a hardware store, outdoor cafes, a
library or post office, and an interesting mix of houses
and people. Not all are high income; some are more
modest working class areas. City planners boast about
the new transit stop with easy access and egress to an
array of employment opportunities. Public works
officials may quickly point to a new bicycle trail
that now connects two formerly separated areas.
Landscape architects relish the enhanced aesthetics
brought by the new public garden established adjacent
to the walking zone. Do any of these benefits directly
counter the problems of congestion, environmental
conservation or public health? Not likely. In contrast,
they claim to enhance the overall experience—either
directly or indirectly—of life in cities.
It is argued that walking and cycling, and cities
designed for these modes, can help increase the
liveability of urban areas and some residents are willing
to pay for the presence of such facilities (Krizek, 2006).
If social capital has been flagged in the social science
literature as an elusive concept to define and measure
(Portes, 1998), liveability proves even more elusive
(Hortulanus, 2000). Compact, walkable and bikeable,
urban forms can allow urban dwellers to conduct their
daily affairs without the need of driving. They can mean
that non-drivers—mainly children, older people and
people with low incomes—are put on a more equal
footing with motorists. Money previously put into road
and transit investments can be redirected to housing,
education, health and recreation. Physical activity can
be gained doing normal daily activities, saving trips to
the gym for those who dislike such things (Calthorpe,
1993; Duany et al., 2000). Together, such urban forms
support the quality of life of urban dwellers.
Despite its challenges with respect to definition and
measurement, liveability appears to be the strongest
policy argument for NMT (Levinson & Krizek, 2008:
210). It has intuitive appeal for voters and decision-
makers.
3.3. Importance of considering walking versus
cycling separately
Conventional thinking about walking and cycling
typically considers them jointly. The above narrative
suggests that the central motivations for these modes
share similar ground and other reasons make sense as
well. Combined, walking and cycling represent less
than 10% of all trips in the US. In addition, they share
many similarities as described below:
Energy source: both modes are human powered and are
considered environmentally benign. Most people in
developed countries eat more than enough to provide
this energy and are even trying to manage potential
weight gain. The energy source may even save money
(i.e., relative to health club memberships).
Exposure to the environment: both modes require
more direct exposure to environmental conditions
than transit or auto. Rain and cold weather are
deterrents for such travel, because they require having
the right attire or protection.
H. Blanco et al. / Progress in Planning 71 (2009) 153–205174
12
Studies include those with a pre–post design related to building a
facility (Evenson et al., 2005; Merom et al., 2003). Others look at
overall physical activity or total walking using a cross-sectional
design have had mixed results, the majority finding significant effects
on travel walking but not on overall physical activity (Forsyth et al.,
2007;Frank, Schmid, Sallis, & Chapman, 2005;Jago, Baranowski, &
Baranowski, 2006a;Jago, Baranowski, & Harris, 2006b;King et al.,
2005;Rodrı
´guez, Khattak, et al., 2006;Rodrı
´guez, Targa, et al. 2006;
Rutt & Coleman, 2005).
Regulation: walkers and cyclists are subject to
regulations, but typically do not need to be licensed.
This means that the age range for participating is
wider than that for driving motor vehicles.
Purpose: both cyclists and walkers may use the mode
for transportation (to work, on errands, at work) or for
recreation (for exercise, relaxation). Many people
combine the two. While this chapter focuses on
transportation uses, it is sometimes difficult to
distinguish purposes.
Burden to carry goods: both modes have limitations in
the bulk and weight of goods that can be transported.
While such concerns can be addressed to some extent,
the casual user may fear being stranded.
Marginalisation: both can be seen as marginal modes,
until recently undercounted in traffic statistics and
rarely emphasised in transportation planning.
Social interaction: because both modes are not
enclosed, it is possible to interact socially with other
cyclists and pedestrians (Oregon Department of
Transportation, 1995).
Such similarities are important to realise. Considering
the modes in a combined sense helps make a stronger
case for incorporating them into planning, including the
important dimension of increased funding. The bulk of
available NMT research, and certainly the policy
attention to date, has considered the two modes jointly.
Considering them together also strengthens coalitions
of interests brought together around NMT topics. Local
and regional planners, health agencies, advocacy groups
and a variety of researchers have coalesced around NMT
as a topic of interest. NMT is no longer solely the
purview of engineers, designers and planners. This has
translated into additional governmental and non-profit
funding for NMT projects and assessments.
From the perspective of both practice and research,
however, aggregating proves troublesome. For planning
purposes, walking and cycling demand different
infrastructure; for research, the behaviours of walkers
and cyclists are wildly disparate and demand different
planning responses. It is likely that future research will
consider walking and cycling independently, and below
we recount why it is important to do so.
With few exceptions, all trips, regardless of mode,
start and end on foot. When combined with other trips,
pedestrian trips are usually short, often no more than a
few city blocks (as their own trip). Pedestrians are
sensitive to distance and will take short cuts where
available, even if these are not designed as such. Most
importantly, the factors that may influence the choice to
walk for travel are likely to differ from those that
influence cycling. For example, the attractiveness of the
route (e.g., interesting facades, a variety of architecture,
the absence of long, blank walls), variety of route
choices, pedestrian safety, and the number of destina-
tions within a walkable distance (e.g., work places or
close-by stores) may affect an individual’s willingness
to walk for transportation (Forsyth, Hearst, Oakes, &
Schmitz, 2008;Hess, Moudon, Snyder, & Stanilov,
1999;Humpel et al., 2004). Until recently, the literature
on the walking environment has been dominated by
urban designers (Gehl, 1987; Jacobs, 1993), with a
sprinkling of technical manuals (Zegeer, 1995).
By contrast, bicycle trips traverse longer distances at
higher speeds than pedestrian trips, requiring longer
corridors (such as wide curb lanes and on-street or off-
street bike paths). Bicycles frequently are considered
street-legal vehicles for most local roadways. The bulk
of bicycle trips, at least in the US, are discretionary.
Whereas most travellers can walk, bicycling applies to a
considerably smaller market of travellers. Cycling
equipment must be stored when not in use. Furthermore,
not everyone owns or has access to a bicycle. During the
summer months in most of the US, the cycling market
includes just over a quarter of the American population,
but there are far fewer year-round cyclists using this
mode for travel rather than recreation (Bureau of
Transportation Statistics, 2003). Bicyclists who share
the road also have unique safety concerns, dealing with
the close proximity of autos speeding by, for example.
The literature on cycling has been more integrated with
general transportation plans, with some manuals for
facility design (Forester, 1994; Hudson, 1982). We
provide Table 2 to describe such differences between
the modes in more detail.
When directly comparing the differences between
walking and cycling, the two modes are more different
than they are similar. Such differences underscore two
points. First, they suggest that any attempt to fully
understand the behaviours of pedestrians versus cyclists
needs to do so using different conceptual models; the
behaviours are too different. As discussed below, even
within each mode, the behaviours for different trip
purposes warrant different approaches. Second, efforts
to account in detail for walking and cycling in future
planning applications also need to do so under different
banners; the infrastructure requirements and environ-
mental supports for each vary too much.
The differences between NMT modes serve to set up
many of the future research needs as they apply to
walking and bicycling. The third part of the chapter turns
to discussing voids in the existing knowledge base and
describing future streams of research that are needed.
H. Blanco et al./ Progress in Planning 71 (2009) 153–205 175
3.4. Specific issues requiring further research
The existing literature on NMT is vast; it can also be
remarkably specific, depending on the topic being
addressed. We definitely know a lot more about walking
and cycling than we did 25 years ago, and even five years
ago. However, like many research topics, the increased
knowledge allows us ask more precise questions.
H. Blanco et al. / Progress in Planning 71 (2009) 153–205176
Table 2
Key differences between walking and cycling.
Dimension Specific to walking Specific to cycling Key differences
Participants Almost everyone except some
with mobility impairments
There are at least three different types
of cyclists
a
: A (Advanced), B (Basic),
and C (Children)
Cyclists demand more specific
environments, depending on
participants or purpose; they also
require heightened physical skills
(e.g., balance)
b
Range/scale Local walking, mostly up to a mile
in length. The average trip length
is 1.2 miles and between 47% and
60% of walking trips are less
than 0.5 miles. Recreation and
work trips tend to be longer
Local and regional cycling. The average
trip length is four miles and 57%
of cycling trips are less than two miles
Cyclists travel much further
Speed Depends on the purpose of trip,
but ranging from 1 mph
(dawdling) to top speeds around
4–5 mph for more active walking
Usually range from 8 mph to 20 mph Cyclists travel much faster
Infrastructure Infrastructure requirements for
safe use include sidewalks and
perhaps paths that are often
preferred, particularly for children
Can share roads with cars, though
with safety issues; lanes and paths
are options; need infrastructure
at destinations (parking, showers)
Cyclists require more
infrastructure at destinations
(e.g., parking)
Infrastructure
planning
responsibility
Local land use planners, and
transportation planners; also
considered in subdivision layout
and urban design
Engineers and transportation planners
responsible for on-road infrastructure;
parks and recreation planners for
off-road infrastructure
Responsibility does not always
coincide, making coordination
more difficult
Trip purpose Transportation (including accessing
other modes, e.g., parked cars,
transit) and for recreation travel
In the US, a clear majority of bicycle
trips are for reasons related to exercise,
health or recreation; cycling for
transportation often plays a stronger
role in many other cultural settings
Cycling primarily viewed as
a recreational activity, at least
predominantly in the US
Safety concerns Crime (real and perceived);
safety from traffic at crossings
and on streets without sidewalks
Safety from traffic, particularly in
narrow streets and at intersections
with roads
Pedestrians tend to be more
concerned about avoiding
areas of high crime; bicyclists’
prominent safety concern often
stems from automobile traffic
Key barriers Distance or perceived distance?
Safety from crime or traffic
Distance. Safety from traffic. Cost
of equipment?
Interface with
automobiles
Mainly at intersections, but also
any locale without sidewalks
Bicycles are often perceived as
unwanted distractions in existing
roadway space; conflicts also occur
where trails intersect with streets
Cyclists often perceived to be
competing for limited roadway
space with automobile drivers
Interface with
transit
Focus on the area around bus or
LRT stops to make them pedestrian
accessibility and attractive for walkers
Require front racks or other means
to accommodate bicycles. Requires
parking at transit stops
Cyclists are more cost
prohibitive to account for
Sources for table:Oregon Department of Transportation (1995),Forester (1994) and Zegeer (1995); statistics from US Department of Transportation
(2002) and Bureau of Transportation Statistics (2003).
a
Class A cyclists are generally considered to be experienced riders who can operate under most traffic conditions. Class B cyclists are the casual or
new adult and teenage riders who are less confident of their ability to operate in traffic without special provisions for bicycles. Some will develop greater
skills and progress to the advanced level. Class C cyclists are pre-teen or other riders whose roadway use is initially monitored by parents or avoided.
b
Oregon Department of Transportation (1995: 36).
After a flurry of work on walking and cycling there is
a need to revisit many fundamental assumptions and ask
some basic questions. An advantage now is that such
questions can be asked at a far deeper and more specific<