New Report Tracks Urban Transit Emissions — Where Does Your City Rank?

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The emissions numbers get worse in less trafficked rail networks, such as the Baltimore Metro (0.919 pounds of CO2 per passenger mile, an average comparable to a car) and Cleveland's rapid rail transit (0.805 pounds of CO2/passenger mile).
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[B' Spokes: Seriously lets start thinking about "rubber rail" so we can put rapid transit where it makes sense rather then just where we have room for it.]

http://dc.streetsblog.org/2010/04/22/new-report-tracks-urban-transit-emissions-where-does-your-city-rank/