The Mass Transit Advantage
MTA's Regional Role in Carbon Reduction: A small increase in transit's carbon footprint typically causes a much larger reduction in the region's carbon footprint.
The MTA prevents about 17 million metric tons while emitting only 2 million metric tons, making it perhaps the single biggest source of GHG avoidance in the United States. The 13 million New Yorkers who live in our service area lead carbon-efficient lives, making New York the most carbon-efficient state in the nation. New Yorkers manage to be efficient without compromising health, lifestyle or income. In fact, we outperform our compatriots in most such indices even as we consume a fraction of the energy and emit a fraction of the GHG. This is the magic of plentiful public transportation. It benefits those who use it and those who don’t use it. It relieves congestion on the streets, insulates people from swings in energy prices, and ultimately, benefits the entire world.
A key concept to understanding the role of mass-transit in the overall sustainability picture is that of carbon avoidance. Three factors play significant roles:
Land Use FactorA local mass transit system allows higher density communities. For example, a trip to the grocery or to a child's school in a transit serviced-community tends to be shorter - and frequently is short enough to walk—than a similar trip in an automobile-dependent suburban community. This land use factor is a major contributor to avoided carbon.
Mode ShiftTransportation generates approximately 40 percent of all green-house gases in the United States, with a large proportion coming from single occupancy vehicles. On a per passenger-mile basis, emissions from single occupancy vehicles are up to five times higher than the per-passenger mile emissions of mass transit.
Congestion ReliefBecause a local mass transit system decreases vehicle traffic, those that remain on the roads are able to travel faster and more efficiently. When mass transit trips are transplanted to roads, congestion goes up dramatically, causing engines to run more inefficiently and longer for the same trip and increasing greenhouse gas emissions.