Four Circles: An Integrated Approach to Behavior-Based GHG Reduction

Come check out my poster session at the 2010 Transportation Research Board’s conference in Washington DC on January 12 at the Hilton: Four Circle Approach to GHG Reduction


“Even if vehicle fuel efficiency were to reach 55 mpg by 2030, we would still see only modest decreases in transportation carbon dioxide emissions without a decrease in vehicle miles traveled.”  This quote from US Department of Transportation Secretary Ray La Hood in his July 14, 2009 testimony to Congress illustrates the growing role that the transportation sector has in meeting climate change objectives through not just vehicle and fuel technologies, but also through addressing travel behavior.  This paper introduces how a “Four Circle Approach” to greenhouse gas (GHG) reduction can be used to support climate change stability, economic relief, and communities that encourage healthier lifestyles.  This approach groups GHG reduction strategies into four categories: 1) Characteristics of the Built Environment: “6 Ds”, 2) Pricing Policies, 3) Vehicle Capacity Constraint, and 4) Transport System Efficiency.  The Four Circle Approach lays out an integrated framework for reducing GHG emissions through changes in travel behavior – specifically a reduction in vehicle miles travelled and a more efficiently used transportation system.   Based on a critique of California’s Senate Bill 375 and developing federal legislation, the proposed framework in this paper seeks to ensure implementation and accountability by directly tying funding to GHG reduction strategies and changes to institutional structures that currently create barriers to meeting national climate change and economic objectives.  The Four Circle Approach would send strong signals to the public that climate change is an important issue through pricing mechanisms and funding priorities; furthermore, the integrated framework would engage the public as part of the climate change solution by providing them tools to make travel behavior choices for healthier lifestyles and communities.

Key Words: greenhouse gas (GHG) reduction; travel behavior; vehicle-miles-traveled (VMT); climate change; transportation funding; metropolitan planning

GAO-09-926T Recovery Act: States’ Use of Highway Infrastructure Funds and Compliance with the Act’s Requirements

Four Circle Approach:

A Proposed Performance-Based Framework for

Reducing Greenhouse Gas Emissions from Travel Behavior