The video begins at 1:49.

Abstract: Policy-makers, researchers, and activists often assume that traffic congestion mitigation results in reduced motor vehicle emissions without proper justification or quantification. This research investigates under which conditions that assumption is valid by comparing trade-offs between increased efficiency and induced travel. Analyses include investigation of varying vehicle fleets - including advanced-drivetrain vehicles. Results demonstrate that higher levels of congestion do not necessarily increase emissions, nor will congestion mitigation inevitably reduce emissions. These results apply for both roadway capacity expansions and traffic flow improvement projects. We compare the emissions effects of various congestion and emissions mitigation strategies, with particular attention to the roll of trucks and the potential of truck-only facilities. Congestion performance measures are also compared for applicability to emissions trends.