BOGOTÁ — Could people start making cleaner air a priority over cars? Cities such as Singapore have successfully cut pollution by restricting car use. Now, perhaps in a sign of our times, people are warming to the idea in the Colombian capital of Bogotá, where cars are still king.

The Catharsis Bogotá project, a polling initiative backed by El Espectador and Despacio, has asked residents to offer their views on how the city could improve life and mobility. In a departure from Latin America's love of personal mobility, many respondents have urged the city to curb car use.

Sustainable transport researcher Darío Hidalgo says it's a notable change of perspective for Colombia, in line with similar developments elsewhere in the world.

Singapore, for example, had a period of immense car congestion as economic conditions there improved, and reached a situation in the 1970s similar to those of many Latin American cities today. At one point, the city-state asked economist William Vickrey to advise it on possible solutions.

His idea was not that Singapore relieve congestion by building more roads or devising complex technological solutions. Instead, he proposed charging car users and owners what their habits were really costing society. In practical terms, that meant imposing enough costs on car ownership (including monthly auctions of registration rights) to triple their sale price. He even formulated the first-ever congestion charging system, which cut traffic jams in half.

Such measures are unpopular and politically risky, but effective. Other cities since have implemented similar measures. There is London's tax on cars entering the city, and Stockholm's modulated charging in keeping with hours and traffic levels. In London, car traffic has declined 20% and in Stockholm, 25%. London has also improved security, increased bicycle use by 72%, and even brought down taxi fares. Public transport has also improved, and demand for it has grown 14%.

Shanghai has used number plate auctions to finance bus technology and cut public transport fares for some residents. Its restrictive measures have at least managed to slow rising car numbers, which grew from around two million in 2004 to 3.5 million in 2010. Comparatively, car numbers in Beijing rose from two million to about five million in the same period.

The Inter-American Development Bank (BID) compiled a report in 2013 on 12 Latin American cities, including Bogotá and Medellín, observing the difficulty of such "demand management" measures. Their unpopularity has basically made car restrictions plunge in priority for politicians, while hampering systematic moves to improve public transport or make it more attractive.

Regional governments have yet to understand that it is often the same cities that charge a premium for buying, driving and parking private cars that also turn out to boast top public transport and better walking and cycling accessibility.