Carbon Emissions and Climate Change

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Carbon Emissions and Climate Change

• A Study of Attitudes and their Relationship with
  Travel Behavior

Prepared for TRB National Transportation
Planning Applications Conference
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Research Questions
Do drivers know what vehicle carbon emissions
are? What are drivers opinions about a link
between carbon emissions from vehicles and
climate change? Are drivers likely to change
travel behavior to reduce carbon emissions? Do
drivers support policies such as using toll
revenue to implement carbon emission reduction
programs?
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Context
Sources of US GHG Emissions, MMT CDE, by Sector,
2007
US Transport Sector, CO2 Emissions, 1947-2007
2 CAGR
Source Emissions of Greenhouse Gases in the
United States 2007 (DOE/EIA-0573(2007)), 3 Dec.
2008
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Context
Source Global Warming on the Road The Climate
Impact of Americas Automobiles Environmental
Defense 2006
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Policy

• To have the greatest chance to slow and perhaps
  even reverse the slide toward calamitous climate
  change, we need to mobilize the widest possible
  public support for effective actions. And to do
  this effectively, we need to understand the bases
  of public attitudes and behavior.

Source PUBLIC ATTITUDES AND BEHAVIOR ABOUT
CLIMATE CHANGE What Shapes Them and How to
Influence Them, Martin Patchen, 2006
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Attitude Towards Climate Change

• Belief is most strongly held by
• Urban residents
• Younger people
• More educated people

Source A Deeper Partisan Divide Over Global
Warming The Pew Research Center for the People
and the Press, 2008
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Behavioral Attitude Towards Climate Change

• There is consistent evidence that peoples
  willingness to take specific environmentally-helpf
  ul actions or support specific pro-environmental
  policies declines as the amount of sacrifice
  connected to the action or policy increases.
• A study of Americans also found that people were
  much more likely to support policies that had no
  clear costs to them personally.
• 90 believe the U.S. should reduce GHG
  emissions
• 77 support CO2 regulations
• 54 support a 5 gas guzzler tax on vehicles lt
  25mpg
• 17 support a 60 cent/gallon gas tax to
  encourage people to drive less and reduce
  emissions.

Source PUBLIC ATTITUDES AND BEHAVIOR ABOUT
CLIMATE CHANGE What Shapes Them and How to
Influence Them, Martin Patchen, 2006
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Attitudinal Segmentation of the UK Populations
Believe but busy believe climate change is
happening but feel that they are unable to act
because they have other priorities
Contributors are prepared to take action
because they believe that small actions by many
people will have an impact on climate change.
Deniers are skeptical that human activity
impacts climate change. May be motivated by cost
and time saving arguments but not by
environmental considerations. Ineffectuals,
believe that climate change is happening but do
not believe that their actions will make a
difference. Aspirationals are younger people,
who are relatively well educated about climate
change but who have lifestyle aspirations that
deter them from taking actions that will reduce
their carbon consumption.
Source Exploring public attitudes to climate
change and travel choices deliberative research
(King et al, 2009)
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Project Locations
Chicago, IL July 2008
Norfolk, VA May 2009
Dallas, TX December 2008
Dothan, AL June 2008
Austin, TX May 2008
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Survey Methodology

• Computer-based stated preference surveys
• Designed to estimate the values of travel time
  savings (VOTs) of potential users of road pricing
  projects
• Multi-method sampling approach
• In-person intercept at activity sites near the
  study corridor
• Hand-out/mail-out postcard invitations
• Employer emails
• Online sample providers

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General Questionnaire Outline

• Questions describing respondents recent trip in
  the corridor
• E.g. purpose, time of day, origin, destination,
  etc.

• Stated preference trade-off questions presenting
  various travel alternatives under different time
  and cost conditions

• Toll attitude questions
• Emissions attitude questions

• Basic individual and household-level demographic
  information, such as gender, age, employment,
  household size, household vehicles, annual
  household income

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Attitude Statements

• Three toll attitude statements
• I will use a toll route if the tolls are
  reasonable and I save time.
• I support using tolls to pay for highway
  improvements that relieve congestion.
• I can generally afford to pay tolls.
• Five climate/emissions attitude statements
• I understand what vehicle carbon emissions are.
• Carbon emissions from my vehicle contribute to
  climate change.
• I am willing to carpool or take public transit
  more frequently to reduce carbon emissions from
  my vehicle.
• I am willing to pay higher tolls if they are used
  to reduce air pollution and carbon emissions.
• I support using tolls to pay for public
  transportation.
• Five point scale from strongly disagree to
  strongly agree

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Attitude Analysis

• A few disclaimers
• Preliminary work
• Stated preference samples are not necessarily
  population-proportional
• Not all questions included in all surveys for
  various reasons
• These are add-on questions to a stated
  preference survey

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Overall Attitudes
I will use a toll route if the tolls are
reasonable and I save time.
Toll Attitudes
I support using tolls to pay for highway
improvements that relieve congestion.
I can generally afford to pay tolls.
I understand what vehicle carbon emissions are.
Carbon emissions from my vehicle contribute to
climate change.
I am willing to carpool or take public transit
more frequently to reduce carbon emissions from
my vehicle.
Emission Attitudes
I am willing to pay higher tolls if they are
used to reduce air pollution and carbon
emissions.
I support using tolls to pay for public
transportation.
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Toll Attitudes
Survey Location

• Higher toll acceptance in Chicago and Dothan
• Lower toll acceptance in Norfolk

Percent Agree
Household Income
Household Income

• Household income is strongly associated with toll
  attitudes

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Toll Attitudes
Respondent Age

• Higher toll acceptance
• Older
• Employed full-time or retired
• Less toll acceptance among students and
  unemployed
• No significant differences found between other
  demographic variables, including
• Household size
• Household vehicles
• Gender

Employment Status
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Emission Attitudes Understanding Emissions
I understand what vehicle carbon emissions are.
Percent Agree
Household Income
Increases slightly with income
Age
Lowest age category least likely to understand

• Very little variation across other demographic
  variables.
• Essentially all respondents reported having an
  understanding of vehicle carbon emissions

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Emission Attitudes Contribute to Climate Change
Carbon emissions from my vehicle contribute to
climate change.
Percent Agree
Decreases as age increases similar to Pew study
findings
Age
Gender
Women more likely to agree
More household vehicles less likely to agree
Household Vehicles
Employment Status
Students more likely to agree
Survey Location
Austin and Chicago more likely to agree Dothan
and Norfolk less
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Emission Attitudes Willing to Change Behavior
I am willing to carpool or take public transit
more frequently to reduce carbon emissions from
my vehicle.
Percent Agree
Decreases as income increases
Household Income
Decreases as age increases
Age
Decreases as number of household vehicles
increases
Household Vehicles
Students most willing to change behavior
Employment Status
Large differences by region
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Emission Attitudes Willingness to Pay
I am willing to pay higher tolls if they are used
to reduce air pollution and carbon emissions.
Percent Agree
Household Income
Almost no variation by income, compared with
large variation in willingness to pay for travel
time savings
Gender
Women more willing to pay to reduce emissions
Household Vehicles
Decreases as number of household vehicles
increases
Employment Status
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Emission Attitudes Tolls for Transit
I support using tolls to pay for public
transportation.
Percent Agree
High income households more likely to support
using tolls for transit
Household Income
Household Vehicles
Decreases as number of household vehicles
increases
Survey Location
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Latent Class Analysis
Cluster Sizes

• Latent Class Analysis was used to group
  respondents into clusters based on their
  responses to the toll and emission attitude
  questions.
• Probability-based classification into unknown
  groups
• Homogenous groups of respondents who share
  similar attitudes

Percent Agree
gt Average
lt Average
Not used as an input variable to the latent
class analysis
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Latent Class Descriptions

• Cluster 1 Ill pay for anything that benefits
  me directly
• Willing to pay to save time.
• Can afford to pay tolls.
• Dont believe they are contributing to climate
  change and dont want to do anything about it.
• Cluster Characteristics
• Higher than average income
• Slightly older
• Skews male

• Cluster 2 Ill do anything to reduce my impact
• Willing to pay to save time.
• Can afford to pay tolls.
• Believe they are contributing to climate change
  and willing to pay more and change behavior to
  reduce impact
• Cluster Characteristics
• Slightly higher income
• Fewer household vehicles
• Skews female

• Cluster 3 I dont believe in climate change or
  double taxation.
• Not willing to pay to save time.
• Cant afford to pay tolls.
• Dont believe they are contributing to climate
  change and dont want to do anything about it.
• Cluster Characteristics
• Slightly lower income
• More household vehicles
• More likely to be from the Norfolk Sample

• Cluster 4 Id like to reduce my impact, but I
  cant afford it
• Not willing to pay to save time.
• Cant afford to pay tolls.
• Believe they are contributing to climate change
  and willing to shift behavior, but not pay extra
• Cluster Characteristics
• Lower income
• Younger
• More students
• Skews female

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Conclusions

• Vast majority of respondents are aware that their
  vehicles emit carbon, but only slightly more than
  half think this is contributing to climate
  change. Even fewer are willing to change their
  behavior or pay to reduce emissions. Support
  decreases as personal sacrifice increases.
• Many people are willing to pay for something that
  directly benefits them, such as saving travel
  time, but fewer are willing to pay for something
  less tangible such as emissions reduction.
• Distinct attitudinal groups exist. What is the
  best way to market policy initiatives to each
  group?
• How do you get 50 of the population (clusters 1
  and 3) to agree that climate change is an issue?
• How do you get them to care enough to do
  something about it?
• More research is needed!

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Questions?