They don't all support the same strategies for coping with it, but US mayors increasingly see climate change as a pressing urban challenge.
One potential benefit of WestConnex, which remains untouched, is that it could relieve Sydney's city centre from cars and make it more pedestrian-friendly.
A sociolinguist wonders if they’ll ever be able to interpret the waves, high beams and middle fingers of human drivers.
Traffic congestion is the main cost that cars create when they use existing roads. Road use charges are a more efficient and fairer way to cover the cost and help ensure traffic flows.
A city-wide experiment suggests well-designed road use charges could ease congestion by encouraging people to drive at different times, take other routes or use other transport.
Millions of Americans rely on public transit to get to school, work or stores, but many can't get the service they need. 'Uberizing' transit by offering more options on demand could fill the gaps.
New research shows that noise pollution in US cities is concentrated in poor and minority communities. Beyond regulating airplane noise, the US has done relatively little to curb noise pollution.
Instead of focusing on freeways, governments should change the way we pay for urban roads and public transport.
Traffic continues to increase, but more slowly than would have been the case if the reforms had not gone ahead.
Building a journalism business model on clicks, cats and Kardashians may have had its day — even as journalists change to keep audiences happy
As the latest controversy about tunnel exhaust stacks and respiratory health plays out in the media, some community members are proposing solutions that just don't make sense.
A recent study finds that noise from human activities is intruding into many parks and other protected areas. Creating quiet zones and noise corridors can help reduce impacts from noise pollution.
Rhino horn trade continues to be a highly lucrative business across the world.
When planning major infrastructure investments, it's important to know which road, freight and information networks are most important – and which proposals might make things worse, not better.
Think you couldn't possibly do without your car? There are more options than you might think.
Traffic wastes time, creates pollution and costs money. But can it also affect us psychologically? A new study suggests that unexpected traffic can increase the incidence of domestic violence.
As self-driving cars proliferate, we need a system to handle difficult situations.
While action on air pollution is welcome, there may be better ways to cut car emissions.
Do you ever feel that the weather is worse on the weekend? Well you might be right!
Driverless cars are the future, right? Wait. While things would be simple if our roads were 100% driverless, getting there is anything but. And planning for roads shared by robots and humans is hard.