Study: Transit, Density Can't Overcome Sprawl on Carbon Emissions

A new study explains how building new transit and density along transit corridors isn't enough alone to reduce carbon emissions in metropolitan areas.

2 minute read

April 8, 2015, 10:00 AM PDT

By James Brasuell @CasualBrasuell


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"A Boston University study published on April 6 in the Proceedings of the National Academy of Sciences shows that a major push in cities like Denver to build dense housing, better transit systems, and more bike lanes in their urban core doesn’t necessarily lead to lower per-capita CO2 emissions," reports Bobby Magill. "That’s because suburbs continue to sprawl and residents there still drive to work."

Although Denver has been celebrated for its recent focus on its urban core, recent reports also show the metropolitan area building residential developments at a much faster pace on the fringes.

The study, according to Magill's coverage, is groundbreaking in its ability measure the impacts of growth in cities like Denver and Salt Lake City: "The study is the first to measure vehicle tailpipe emissions in major metropolitan areas by using highway traffic data over a period of time—information crucial for city planners to know their city’s impact on the climate, and to find ways to reduce their carbon footprint."

More on that point: "Conor Gately, a graduate student at Boston University’s Department of Earth and Environment and the paper’s lead author, said his team created the first nationally consistent map of vehicle CO2 emissions at a one kilometer scale over a span of 33 years between 1980 and 2012. Previous studies were limited to a single year or measured emissions at a state or national level, he said."

The article includes a lot more about the implications of the study as well as some of the debate that has already emerged over its findings. 

Monday, April 6, 2015 in Climate Central

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