Last year, the population of the U.S. reached 300 million for the first time. Thirty-six years from now, in 2043, the population will hit 400 million, according to demographers. That’s 100 million more people who will have to share our air, water and other natural resources.

They’ll also have to share our roads and highways, already highly congested in many urban and suburban areas. You think traffic is bad now, just wait! You think fuel prices are high now, just wait! You think most motorists are lousy drivers now, just wait! By comparison, today’s era will be thought of as an idyllic period of trouble-free mobility.

Of course, by 2043, we’ll have dug ourselves out of the huge hole that we’ve been digging for the past 100 years. Scientists will have found a way to reverse all of the damage that we’ve done to the planet and roll back the environmental clock to the 1600s. Yes, I’m being facetious here. We need to change — now
Although public transit ridership has been on the rise, apparently due to the high cost of fuel, people still aren’t ready to give up their cars in any significant way. They’re still not convinced that what they do today to help preserve the environment will have an impact 36 years from now when their children or grandchildren are competing for scarce resources like breathable air, drinkable water and untainted food. Or maybe they do believe that climate change is real, and global warming presents an actual threat to the planet — and they just don’t care.

To a point, it doesn’t matter what people think, it only matters what they do. And what they do is something that can be influenced by what this industry does. The concept of sustainability is a good one, and needs to be applied — and marketed — by everyone who provides public transportation.

Why should people use public transportation instead of driving their cars? I’ve got 400 million reasons. Why should they recycle their bottles, cans, paper and plastic? I’ve got 400 million reasons. You get my drift. Let’s get their attention
To get people’s attention, you need to surprise them. A large number, like 400 million, can be surprising. But a number like 425 million is about 5.9% more surprising. That’s the number of cars that motorcoaches take off the road each year, helping to reduce congestion and pollution. The American Bus Association used that fact recently in an Earth Day promotion.

Even better, take a high number and then use a graphic illustration to reinforce its importance. For example, APTA recently reported that 2006 ridership topped 10 billion for the first time in 49 years. It used a graphic of one-gallon fuel containers stacked from the Earth to the Moon to wonderfully illustrate how much fuel was saved by those 10.1 billion rides on buses and railcars.

With the sustainability movement gaining traction across the world and fuel prices starting to tip toward record highs again, this is an auspicious time for public transportation providers to market their products. We need to push hard, maybe focusing on the car buyers of the future — young people — to drive home the message that our society can’t continue to keep digging that hole without a day of reckoning. Eventually, 36 years from now, 400 million Americans are going to be living in that hole, many of them too young to blame and many too old to care.