Transformative Public Transportation Solutions for Reducing Greenhouse Gas Emissions

Focus Area

Climate Change


Air Quality, Environmental Process







Research Idea Scope

Most studies to date have relied on annual percent increases from baseline transit ridership in order to project the greenhouse gas emission reduction potential of transit investments. This study would take the opposite approach, looking at transit achieving a significant mode share in particular markets, what that would mean for emissions, and what it would take to get there.  
The objective of the research is to provide scenario building and analysis of localized, transformative public transportation solutions. Important analysis areas include thresholds at which transit serves a large enough number of destinations and/or offers service at equal to or better travel times than driving to achieve a significant market share. The research would take a market segmentation approach, focusing on specific markets that offer the best opportunities. The research would also examine particular U.S. or international cities that have gone through a transformation from auto dominant to multimodal transportation. The research would seek to determine what factors led to success in these cities, including factors such as political decision-making processes, implementation, public opinion, economy, etc.
Related Work
·      Cambridge Systematics, Moving Cooler, 2009.
·      TCRP Report 93
·      TCRP SH-09 (to be released soon)
·      TCRP New Paradigms for Transit
Draft transportation reauthorization legislation and climate change legislation being considered in Congress would require states and metropolitan planning organizations to set transportation GHG reduction targets and develop strategies to meet these targets. Solid information on the impacts of combined strategies on reducing transportation GHGs is crucial to the ability to develop these strategies. The study would also inform the federal government’s livability initiative.

Urgency and Payoff

States and metropolitan planning organizations could use analysis produced by the research in developing transportation plans that include GHG reduction strategies. Communities could also use the analysis to help them achieve successful public transportation solutions.
The project would help the transportation sector reduce greenhouse gas emissions, a very important goal as transportation accounts for about a third of U.S. carbon emissions and science indicates that emissions must be reduced substantially to avoid dangerous climate change impacts.

Suggested By

RNS. Sponsoring Committee: A0020T, Special Task Force on Climate Change and Energy Source Info: Special Task Force on Climate Change and Energy January 2010 Workshop