Traffic wave

Traffic waves, also called stop waves or traffic shocks, are traveling disturbances in the distribution of cars on a highway. Traffic waves usually travel backwards in relation to the motion of the cars themselves, or "upstream". The waves can also travel downstream, however, more commonly become "pinned" to a single spot on the road, as a soliton. Traffic waves are a type of traffic jam. A deeper understanding of traffic waves is a goal of the physical study of traffic flow, in which traffic itself can often be seen using techniques similar to those used in fluid dynamics.

Mitigation
It has been said that by knowing how traffic waves are created, drivers can sometimes reduce their effects by increasing vehicle headways and reducing the use of brakes, ultimately alleviating traffic congestion for everyone in the area. However, in other models, increasing headway leads to diminishing the capacity of the travel lanes, increasing the congestion.