The traffic cop: Earth's new best friend

Most of the debate among environmentalists over the automobile centers around which technologies are the greenest: hydrogen fuel cells, plug-in hybrids, or biodiesel, to name just three contenders. But the real question facing society as a whole isn't how to power the cars of the future, but how to reduce the amount of time we spend driving what is, after all, an extraordinarily wasteful use of finite resources.

Heavy traffic in Sydney, Australia / Reuters

Any sensible solution will have to involve both carrots and sticks. Carrots in the form of more attractive and more widely available mass transit alternatives, and sticks in the form of taxes and levies. The latest U.S. city to consider the latter half of the equation is San Francisco, which is pondering a $3 toll "to enter, leave or pass through parts of San Francisco during morning and evening commutes."

This will no doubt infuriate the masses. But experience elsewhere suggests the benefits outweight the costs. The now widely accepted and appreciated eight-pound charge for driving into the center of London is well known. It cut some greenhouse gases by 20 percent in its first year. But it's not the only success story.

Stockholm recently introduced a similar charge on a trial basis. According to Reuters, "traffic was reduced by 22 percent, rush hour travel times were almost a third shorter, accident rates fell and emissions of greenhouse gases dropped 10 to 14 percent."

This is the kind of thing that we're all going to have to get used to if we're serious about getting a grip on global warming. As a new report from Britain's Energy Research Centre says:

Deep cuts in carbon dioxide (CO2) emissions consistent with the UK's 80% greenhouse gas emission reduction target by 2050 are technologically and economically feasible. However, these cuts will require fundamental shifts in technology and behaviour.

Now, so long as San Francisco follows through and uses the proceeds from the toll to improve public transit...