Henry Ford's vision to create cars "for the great multitude" has been far better received than anyone could have imagined.
More than a century since the Model T was introduced, global demand for personal vehicles is stronger than ever, particularly in the developing world, where people want cars for improved mobility and as status symbols. But as car culture spreads, vehicles are clogging up city streets and threatening the planet with harmful emissions.
Automakers have invested billions in lightweight materials and low-carbon fuels to drive down greenhouse gas emissions from cars and trucks. But these technological advances will mean little if consumers' desire to own large, powerful vehicles continues to grow.
And even if people do choose to buy cleaner cars, cities have only so much space to put them in. Congestion in and around cities will continue to worsen unless populations support policies that curb vehicle usage.
The International Panel on Climate Change (IPCC) Fifth Assessment Working Group III report, released in April, recognized the need: "Behavior, lifestyle and culture have a considerable influence on energy use and associated emissions, with high mitigation potential in some sectors, in particular when complementing technological and structural change."
But according to Felix Creutzig, group leader at the Mercator Research Institute on Global Commons and Climate Change in Berlin and lead author of the IPCC's transport chapter in Working Group III, the academic community has yet to fully assess how lifestyles and behavioral elements are driving car use and has yet to measure people's willingness to change.
Can commuters be persuaded to willingly give up the freedom of personal mobility? Can a growing middle class be persuaded to downsize its vehicle purchases? Can some drivers be persuaded to pay more for driving so that people will drive less overall?
"I think that this is a gap, also in the literature, to comprehensively assess the effects of human behavior and what can be done about it," Creutzig said.
Yearning for classy cars in China
The world is currently experiencing unprecedented growth in vehicle adoption. According to the Global Fuel Economy Initiative, the global fleet is expected to triple between now and 2050, with developing countries accounting for 80 percent of the expansion.
In 2010, China overtook the United States as the largest new-car market. But Chinese consumers aren't just buying any cars; they're gravitating toward bigger, more polluting ones. Research by consulting firm McKinsey & Co. determined that sales of sport utility vehicles in China will triple between 2011 and 2020, although sedans will remain the largest segment overall.
The market for premium cars in China is also growing rapidly. A 2013 McKinsey study found that China's premium car market will grow at an annual rate of 12 percent through 2020, compared with 8 percent for the passenger car market overall. At this rate, China could overtake the United States as the largest premium car market as soon as 2016.
Respondents in a survey of Chinese car owners cited "reflection of social status" and "self-indulgence" as the top reasons for purchasing a premium vehicle. Some said the cars were viewed as a "business card" for credibility.
China, which has an authoritarian regime, has dealt with rising vehicle demand by implementing a license plate lottery system in traffic-congested cities. Democratic countries generally have a harder time enforcing such policies.
Class barriers in South Africa
Local factors play a big role in changing attitudes. Johannesburg, South Africa, for instance, initially struggled to win support for its energy-efficient Rea Vaya bus rapid transit (BRT) system because of deep societal divisions.
One challenge was to overcome class barriers and persuade professionals to choose public transit over their personal cars, said Rehana Moosajee, former member of the Johannesburg mayoral committee for transport. Another issue was to get the informal sector of minibus taxi drivers to embrace Rea Vaya. Many of the drivers protested the bus system, and in several incidents, gunmen opened fire on BRT buses.
"One of the efforts, of course, was to attempt to get them to grapple with issues of climate change and so forth," Moosajee said. "But I really do believe that when you're wanting people to make behavioral changes, that you have to move beyond arguments that sound fairly remote and fairly academic and move into arguments that actually resonate with people based on their perspective."
"Getting [the drivers] to a point where they realized their biggest competitor was in fact the growing use of the private car and a one-person, one-car culture was when they finally began to realize that the bus system was not the biggest threat to their business," she said.
According to a recent report by the RAND Corp., income alone does not determine the demand for personal vehicles in developing nations. Whether or not a society has a car culture also plays a role, among other factors such as low vehicle taxes, fuel prices and the availability of vehicle alternatives.
"There are reasons people own cars beyond just the utility of being able to travel at your own convenience," said Liisa Ecola, a senior project associate at RAND. "So even though they might not need a car, people may buy them. And people's choice of which car they buy is often motivated by other cultural factors, like social status and an idea of a car and extension of your own personality and identity."
While not yet at the level of car-loving countries like the United States, Australia and Germany, the favorability of car culture in Russia, India and China will soon reach the levels of some highly developed nations, the report predicts.
Milan lures people out of their cars
The report also finds that policies can shape driving trends. But getting populations to support those policies is another matter, Ecola said.
Setting up trial programs is one effective way to show constituents how a policy like a congestion charge would work without making a full commitment, she said.
In 2011, Milan started an 18-month demonstration of a congestion charge designed to reduce chronic traffic jams and critical smog levels in the Italian city. Last year, the $7 fee to enter "Area C" was made permanent following a referendum that saw 79 percent public approval.
Since Milan's system was put in place, the number of cars in Area C has dropped by 30 percent, demand for street parking is down by 10 percent and the productivity of freight deliveries within the city is up by 10 percent. Emissions also fell. Particulate matter was reduced by 10 percent and carbon dioxide by 35 percent.
In May, the city of Milan received an award from the Organisation for Economic Co-operation and Development's International Transport Forum (ITF) for its achievements.
"I think that people nowadays are very happy with the solution," city representative Maurizio Baruffi said in an interview. "Also, because we have public transport and ... we have a system of bike sharing and car sharing in the center of the town, people can move very quickly and very easily with fewer problems to do with pollution and congestion."
Some cities can't say 'enough'
Other cities' attempts at implementing road charges haven't gone so well. Voters in Manchester, England, and Edinburgh, Scotland, shot down the idea, and New York's pricing system proposed in 2007 failed to get the political support it needed to move forward.
Jose Luis Irigoyen, World Bank director for transport, water, information and communications technologies, said that changing hearts and minds isn't only an issue in the transportation sector; it's also a barrier to broader sustainable development.
"At the World Bank we realize that when you talk about climate change, when you talk about road safety or when you talk about sanitation, for example, in some countries where this is a problem, it is about changing behaviors," he said on a panel this spring at the ITF summit in Leipzig, Germany.
Social media campaigns can be an effective way to get people on board. Top-down leadership from decisionmakers can also encourage a critical mass to follow suit. In some cases, he acknowledged, only the sheer severity of an issue can get people to act.
But waiting for traffic congestion, air pollution, road deaths and other issues to get worse before taking steps to implement a solution "is a horrible way to see the problem," he added.
"In highly developed countries today, the situation got worse until society said, 'Enough.' We call that the tipping point," Irigoyen said. "What is at stake now is how we help developing countries ... avoid having to spend 30 years going through this process and reaching that tipping point much faster."
Correction: An earlier version of this story misstated Felix Creutzig's title.
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