GreenSpace: Our love affair with the car: On the rocks, or a rough patch?

It's unlikely many people will agree with Lester Brown, but he's interesting and thought-provoking, so here goes:

Brown thinks we're losing our love for the automobile.

The founder of the Earth Policy Institute, an environmental think tank and advocacy group, makes a good case with data he has drawn from government agencies.

Last year, he says, for the first time in 60 years of uninterrupted growth, the size of the U.S. auto "fleet" declined. That's because scrapped cars outpaced new-car sales.

He thinks it's likely to continue shrinking.

He contends we've reached market saturation. With more cars than drivers - 246 million registered motor vehicles to 209 million licensed drivers - he says we couldn't get all our cars on the road at one time if we wanted to.

Brown also notes the increasing shift of the U.S. population from rural areas to cities, with more public transportation. Then there's the specter of higher gasoline prices and mounting concerns about climate change.

Not to mention the literal cost of traffic congestion - $87 billion in 2007, according to the Texas Transportation Institute, including gas used while idling and lost work time.

In a carrot-and-stick approach, many cities, including Philadelphia, are adding bicycle lanes and increasing parking rates - so much so that they're installing credit-card devices instead of coin-operated meters.

Kids aren't so auto-enthused. In a nation with 17.7 million youths 16 to 19, just 9.9 million, or 56 percent, have driver's licenses, a percentage that has been dropping since the early 1980s.

Brown contends young adults are absorbed in social media instead of driving around, which was the prime social activity of Brown's youth in South Jersey. (How today's teenagers replace necking in cars is unclear. Is there an app for that?)

"We're looking at a cultural shift, which is new, in addition to the more traditional economic forces," Brown says.

Dream on, others counter.

Last year was an economic disaster, and discerning a trend is impossible, says David Hyatt of the National Automobile Dealers Association.

Plus, although Brown says people are moving to more fuel-efficient vehicles, note this: The top-seller last year was the Ford F-series pickup truck, says association chief economist Paul Taylor. (Next were Toyota's Camry and Chevy's Silverado pickup.)

Like all vehicle sales, hybrids dropped, but not as far.

Although Brown's info seems correct, his characterization of the American attitude is probably "aspirational," contends Therese Langer, transportation director for the American Council for an Energy-Efficient Economy, an advocacy group.

Change is coming, "but certainly not fast enough."

For the nation to reduce emissions 80 percent by 2050, and assuming the burden would be shared equally by all sectors, we need 80 percent fewer automobiles. Or they need to be five times more efficient. More likely, a combo of the two.

Last week, the organization released its "greenest" rankings for 2010 models at www.greenercars.org, topped by Honda's natural gas-powered Civic GX, followed by the Toyota Prius and the Honda Civic Hybrid.

Green cars have a lot of potential. Last week, Environment America released a report indicating that if half the vehicles in the United States were powered by electricity by 2030, total global-warming pollution of the U.S. fleet would be reduced 62 percent.

They would result in far less smog-forming emissions and use much less oil.

Green cars hardly overwhelm the list at the Convention Center auto show Saturday through Feb. 7, but they'll be there.

The Chevy Volt, a plug-in hybrid due this year, will surely attract attention, and the all-electric Tesla Roadster ($101,500) will lure the wealthy and the dreamers.

Other hybrids on the show's dance card so far are the Honda Insight, Toyota Prius, and - don't laugh - big-'un hybrids including the Chevrolet Tahoe, GMC Denali, and Cadillac Escalade.

One that won't be there is the chipper little Tata Nano, a European car that, like the Smart car, is so small you could just about pick it up and carry it into a tight parking space. (Just 122 inches long, you might even fit two.)

One critic dissed it as a "cute death trap," but hey, it gets 70 m.p.g.

Dealers are facing stricter fuel economy standards, but American buyers will also greatly affect how fast we move to cleaner vehicles. Each purchase is a vote.

Either way, if Brown thinks the American love affair with the car is waning, "you tell the 250,000 people that are going to come to the Convention Center for nine days," says Kevin Mazzucola, executive director of the show's sponsor, Auto Dealers Association of Greater Philadelphia.

They'll be paying to ogle the latest models. And most probably will have gotten there . . . by car.