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Driving Global Warming: Commuting in Massachusetts and its Contribution to Global Warming 2/7/2006 drivinggw.pdf News Release

Executive Summary

As the new home of MASSPIRG's environmental work, Environment Massachusetts can be contacted regarding this report.

Transportation is the leading source of global warming emissions in Massachusetts. The state’s cars, trucks and other transportation vehicles emit more carbon dioxide – the leading global warming gas – than the entire economies of more than 140 other nations, including Peru, Croatia and Lebanon.

The trips Massachusetts residents make to and from work are major contributors to the problem. Commuting is directly responsible for 5 to 8 percent of the state’s carbon dioxide emissions and the decisions that influence commuting – such as where to live and where to work – influence the trips people make for other purposes as well. To reduce global warming emissions from cars and trucks – and to meet the state’s climate protection goals – Massachusetts must find ways to reduce the global warming impact of commuting.

In order to find the right policy options for confronting global warming emissions from commuting, it is necessary to know who is commuting where and by what mode of transportation. A review of data collected by the U.S. Census Bureau identifies which towns in the commonwealth are responsible for the greatest amount of commuting-related emissions of carbon dioxide (the leading cause of global warming) and suggests ways that the state can effectively reduce emissions.

The growth of suburban employment and the explosion of “exurban” residential development in formerly rural areas of the state pose major challenges to the state’s efforts to reduce global warming emissions.

• Many of Massachusetts’ fastest-growing communities are located on the extreme fringes of the state’s metropolitan areas, where per-worker emissions are very high. These “exurbs” often serve as bedroom communities for two or more cities, making the delivery of high-quality transit service very difficult.

• Long-distance commutes are responsible for an increasingly large share of global warming emissions from driving. The 2 percent of Massachusetts commuters who travel more than 30 miles to work were responsible for about 11 percent of the state’s commuting-related carbon dioxide emissions.

• While a large percentage of commuters traveling to Boston use transit and other low-emission transportation alternatives, the majority of commuters traveling to towns just outside the city – many of which have substantial transit infrastructure – drive to work alone. (See Fig. ES-1.) Promoting transit connections in these “core suburbs” could significantly reduce commuting emissions.

The average commuter living in parts of the South Shore and in north-central Massachusetts produces three to four times more carbon dioxide from his or her daily commute than the average commuter living in Boston.

• Among towns with significant commuting-related carbon dioxide emissions, Plymouth ranks first for annual carbon dioxide emissions per commuter, with several other South Shore towns just behind. Cambridge, Brookline, Somerville and Boston commuters produce the lowest average emissions, with the average Cambridge commuter emitting one-sixth the amount of carbon dioxide as the average Plymouth commuter.

Commuters traveling to workplaces in the Interstate 495 belt produce significantly more emissions than those traveling to workplaces in Boston and nearby towns.

• Commuters traveling to Marlborough, Westborough, Littleton and Andover – all of which are located along Interstate 495 – produce the highest amounts of per-commuter emissions by place of work. By contrast, workers traveling to communities in and around Boston produce significantly lower amounts of emissions. (See Figure ES-3.)

Increasing residential population density, shifting more commuting trips to transit, and encouraging workers to live near their place of work can reduce carbon dioxide emissions from transportation.

• Regardless of their location within the state, towns with higher residential population density, high rates of transit use, and short average commute lengths tend to have lower average per-worker emissions of carbon dioxide.

Massachusetts should take a series of immediate and long-term actions to reduce global warming emissions from commuting. Among other actions, the state should:

Reduce Vehicle Emissions

• Implement vehicle global warming emission standards and adopt other measures to encourage the purchase of vehicles that produce less carbon dioxide per mile driven.

Promote Transit and Transportation Alternatives

• Invest in the core MBTA transit system and other regional transit systems to maintain high service quality and keep fares low.

• Improve transit connections to allow suburban commuters to more easily reach jobs in a variety of towns near Boston, improve transit service to suburban “edge cities” that increasingly serve as centers of employment, and improve transit service in other areas of the state to reduce the number of single-passenger automobile commutes.

• Hold suburban workplaces accountable for the carbon dioxide emissions they generate by strengthening requirements that employers implement commute-trip reduction programs and providing greater programmatic support.

• Extend the regional transit network to promote connections with residential and work locations in neighboring states.

• Develop programs to encourage residents to live near their workplaces and to encourage employers to implement telecommuting.

Promote More Efficient Land Use

• Put the brakes on exurban development in rural areas by encouraging urban redevelopment, the creation of affordable housing, and mixed-use planning.

• Encourage transit-oriented development.