I’m sharing this article on phantom traffic jams:

Seibold, B. (2019) Traffic Ghost Hunting: When the biggest problem with traffic is nothing at all, Nautilus, https://medium.com/@NautilusMag/traffic-ghost-hunting-ac071197695d [Last accessed: 4/9/2019]

Have you wondered why the road or path is congested only to find out there seems to be nothing causing it? This is the phantom or ghost traffic jams caused by simple behaviours of travellers whether on motor vehicles, cycles or people like slowing down their movement or changing lanes. These disruptions cause a “ripple effect” on the traffic stream much as like waves are generated by a stimulus on calm waters.

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