Transportation's Role in Reducing U.S. Greenhouse Gas Emissions ...

Transportation's Role in Reducing U.S. Greenhouse Gas Emissions: Volume 1
3-20
them to the same baseline as that used in this report to Congress, yields a
reduction of U.S. transportation GHG emissions of 1 to 4 percent in 2030 and 3 to
8 percent in 2050. 93 The Moving Cooler study assumptions, which fall in the
middle of the range, rely on 43 to 90 percent of new urban development
occurring in areas of roughly greater than five residential units per acre, which
accommodates single family and multifamily homes. 94
It does not assume
changes in rural development. GHG reductions from land use change increase
over the long term, as land use patterns evolve over long periods of time due to
the resilience of the existing housing stock and transportation infrastructure.
Transit, nonmotorized improvements, and pricing would be most effective over
the long term if they are implemented in combination with more compact and
better integrated land use patterns that reduce overall trip lengths and make
alternative modes viable as a means of travel for many trips. Land use changes
can often be implemented with very little public investment cost, with the
primary direct costs including knowledge sharing, outreach, and planning
activities. Additional infrastructure investments, or other costs such as
brownfields cleanup, may be needed in some locations, but on the whole more
compact land use patterns have been demonstrated to provide long-term cost
savings through reduced roadway and other infrastructure requirements. While
land use planning is conducted at the local level, the Federal government could
encourage changes to land use patterns by funding State and regional planning
activities to coordinate local policies; building State and local capacity to
understand, model, and assess sustainable development principles within project
planning; and by providing incentives and/or disincentives through
transportation funding mechanisms.
Commuter/worksite trip reduction programs have modest potential for GHG
reductions—0.2 to 0.6 percent of all transportation sector emissions in 2030. The
most effective actions from a policy perspective are trip reduction requirements
combined with supporting activities such as regional rideshare and vanpool
programs and financial incentives for the use of alternative modes. Federal
funding for aggressive public outreach programs to encourage employers to
offer travel alternatives could be effective even in the absence of mandates.
Telework and other alternative work schedules can further reduce GHG from
work travel by up to 0.5 percent, although telework is likely to spread largely
through private initiative and the role of the public sector in encouraging
adoption of alternative work schedules appears limited. 95
Most public information campaigns exhibit modest GHG reduction potential—
in the range of 0.1 to 0.2 percent of transportation GHG emissions, although most
93 Vol. 2 Sec. 5.4.
94 For visuals of different density levels, please see Vol. 2 Sec. 5.4.
95 Vol. 2 Sec. 5.5.