A recent study led by climatologist Nadine Unger of NASA’s Goddard Institute for Space Studies has concluded that motor vehicles, as a sector in the economy, are “the greatest contributor to atmospheric warming now and in the near term.” The second greatest contributor, by sector, is the burning of household biofuels such as wood and animal dung. Third is raising livestock, particularly cattle.
So, how should we knock the transportation sector off the podium? One way that California is pioneering is a low carbon fuel standard. The basic idea is to reduce the carbon intensity of motor vehicle fuel per unit of energy. My colleague Roland Hwang has blogged about this here.
Another tactic that California is pursuing is restricting tailpipe emissions of CO2. After a politically-driven and unscientific decision by the Bush Administration EPA blocking California rulemaking was reversed, California’s AB 1493 (the “Pavley Act”) is on its way to reducing global warming emissions from cars in California, and in other states that have adopted similar laws.
A third way to reduce global warming from the transportation sector is to improve our public transit system so that fewer people need to drive personal vehicles. My colleague Lizzeth Henao blogged here about recent progress in funding public transit projects in Southern California.
Not surprisingly, the auto manufacturers fought AB 1493 in court (and lost) and various industries are fighting the low carbon fuel standard in court. And we can expect the highway lobby to try to suck up all the transportation dollars it can.
I hope that these fights can be won. If not, we’ll be driving our cars into a very dangerous future.