“What most intrigues me is that rates of car ownership per household and per person started to come down two to three years before the downturn,” said Michael Sivak, who studies the trend and who is a research professor at the University of Michigan’s Transportation Research Institute. “I think that means something more fundamental is going on.”

If the pattern persists — and many sociologists believe it will — it will have beneficial implications for carbon emissions and the environment, since transportation is the second largest source of America’s emissions, just behind power plants. But it could have negative implications for the car industry. Indeed, companies like Ford and Mercedes are already rebranding themselves “mobility” companies with a broader product range beyond the personal vehicle.

“Different things are converging which suggest that we are witnessing a long-term cultural shift,” said Mimi Sheller, a sociology professor at Drexel University and director of its Mobilities Research and Policy Center. She cites various factors: the Internet makes telecommuting possible and allows people to feel more connected without driving to meet friends. The renewal of center cities has made the suburbs less appealing and has drawn empty nesters back in. Likewise the rise in cellphones and car-pooling apps has facilitated more flexible commuting arrangements, including the evolution of shared van services for getting to work.