Transmilenio municipal buses are seen on a street of Bogotá, Colombia (from a post first published here).

Transportation is responsible for roughly a quarter of global greenhouse gas emissions. This means that bold changes in transportation policies — for both the developed and developing world-must be part of solving the climate crisis. The trick is to curb the world’s emissions — from industry as well as transportation-without preventing poor countries from developing and lifting their people out of poverty. The New York Times recently highlighted a promising mass transportation solution that could help make this possible: bus rapid transit, or BRT. This mode of transportation, which works like an above-ground subway, is already helping reduce emissions and fight poverty around the world, and could do even more if it gets a boost from the U.N. treaty in Copenhagen this December.

BRT puts long, sleek buses on exclusive lanes protected by physical barriers. In well-designed systems such as Bogotá’s, the buses stop at enclosed, elevated stations. Passengers pay their fare before boarding. These features — along with clear route maps, feeder buses, and free transfers between lines — allow BRT to achieve the speed, capacity, and reliability of a subway at a fraction of the cost. The idea has been around for decades, but has only gained momentum since the triumph of Bogotá’s TransMilenio. Good planning, rather than novel technology, is the key to a successful BRT.

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BRT reduces smog and traffic. Bogotá’s TransMilenio has made Colombia’s sprawling and chaotic capital city much more livable: A 40-percent drop in air pollutants was reported in the first year of the system’s use, and average travel times were 32 percent shorter.

The system also reduces greenhouse gases by introducing fewer, cleaner buses and coaxing people from their cars. By removing 7,000 small private buses, TransMilenio has allowed Bogotٔá to reduce its emissions by more than 59 percent since the system’s opening in 2001. And BRT could cut nearly three times more emissions than light rail powered by coal-based electricity.

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It’s cost effective, as well. BRT is much cheaper than subways and faster to install. This makes it an attractive option for booming cities in Latin America, Asia, and the Middle East facing massive transportation problems.

Bogotá’s system is a flagship and a model for cities worldwide because of its excellent planning and implementation and its success in helping to lift the city out of poverty. BRT systems are now under construction in all of Colombia’s major cities and around the world: Sixty-three systems are operating on six continents, and 93 more are being planned. Notable BRT cities include Jakarta, Istanbul, Mexico City, Johannesburg, and Beijing.

Massive deployment of BRTs, where appropriate, could be part of the answer to avoiding catastrophe while ending poverty. Globalemissions linked to transportation are set to double by 2030. Eighty percent of this growth will come from the developing world, where major cities are already struggling to provide mobility to their exploding populations. The global climate treaty that will be hammered out in Copenhagen must confront this problem in addition to addressing energy generation, efficiency, and deforestation.

The treaty could finance the massive planning and construction that will be needed to expand BRTs through carbon offsets. In fact, Bogotá’s BRT was recently the first transportation project to receive funding through the Kyoto Protocol’s Clean Development Mechanism, or CDM. Under the CDM, industries in the developing world that manage to reduce their emissions receive credits that they can sell to polluters in industrialized countries looking to reduce their footprint. Bogotá will be selling 250,000 tons of CO2 equivalent to the government of the Netherlands in the coming years. This offset scheme could be a way for developed countries to meet emissions caps, as is currently being proposed to fund anti-deforestation efforts.

Thankfully, China and India — the two major emitters in the developing world-seem to be embracing such a technology. More than 30 projects are being implemented or studied in China alone. Their robust adoption of this and other efficient mass transport solutions will be critical.

But there’s no good reason why industrialized countries shouldn’t also consider BRTs as they look for ways to decarbonize their transportation systems. BRTs are cheap and could be deployed rapidly where appropriate. Most of the barriers to bringing them here are political — unsurprisingly, they face stiff opposition from the car industry. Still, the Obama administration and local communities across the country should take a hard look at this emerging solution. Electric cars are good, but fewer cars are even better.