What too much traffic does to our environment — and to us

Getting into a traffic jam is every driver's nightmare. Endless minutes (or worse: hours) in which nothing's moving forward can turn what should be a short car-ride into a seemingly never-ending odyssey. But congested streets aren't just annoying for commuters — they have far-reaching consequences.

Turn off your engine when you get into a traffic jam! You'll save fuel after 20 seconds of standing still already. Letting your engine run while your car's idling burns one liter of fuel an hour, according to Germany's technical inspection agency TÜV Süd. A higher fuel consumption rate means that more CO2 is blasted into the atmosphere, which we should avoid if we want to fight global warming.

Germany saw roughly 745,000 traffic jams in 2018, according to German automobile club ADAC. That's a three-percent increase compared to 2017. According to GPS-maker TOMTOM's last survey, Cologne's streets were the most congested (as shown above). On average, travel time increased by more than a third because of congestion, compared to free flowing traffic.

GPS-maker INRIX uses different calculations and has identified Munich as Germany's traffic jam capital. Drivers there were stuck in congestion for an average of 51 hours a year. That's nothing compared to the world leaders: The world capital of traffic jams is Los Angeles, where drivers were stuck in traffic for 102 hours a year, followed by Moscow (pictured here) and New York with 91 hours each.

People who are stuck in traffic frequently have to deal with serious health problems. When traffic isn't flowing as it should, your body releases stress hormones. Your immune system is weakened and your blood pressure rises. People who are frequently stuck in traffic jams, like commuters, are even likely to develop burnout syndrome.

According to INRIX, the costs caused by traffic jams in Germany amounted to 80 billion euros in 2017. Goods don't reach their intended recipients on time and more fuel is burned. Both companies and private drivers suffer financially. Traffic jams "threaten economic growth and stunt quality of life," INRIX head economist Graham Cookson said.

For a while hopes were high that ride-sharing services like Uber would bring down traffic. If people could easily get a ride, maybe they'd leave their own cars in the garage more often! But traffic researcher Bruce Schaller found out that the opposite was true in US cities. People took Uber instead of the subway or their bikes, while car owners kept driving their own vehicles.

Afghanistan's capital Kabul is also dealing with congested streets. But that's not the only factor contributing to dangerous air pollution. In winter residents have taken to burning coal, car tires and trash to generate heat. Add to that diesel generators and many, many cars and you get smog that Afghanistan's National Environmental Protection Agency (NEPA) calls "deadly."