How we behave in a traffic jam?

What causes a traffic jam and why do motorists react differently to congested situations on the road?

These are the questions posed every day by members of a research project at the University Duisburg-Essen in Germany’s most densely-populated state, North Rhine Westphalia.
Every traffic participant in Germany spends an average of 60 hours a year in a traffic jam, making a total of 4.7 billion hours or 529,000 years, the researchers headed by Professor Michael Schreckenberg found.
Traffic jams cost the German economy about $314 million per day in lost working hours, delayed deliveries for just-in-time production and pollution, according to independent studies.
But with growing public resistance to the building of more motorways in Germany, authorities are being forced to look at more intelligent ways of utilising the existing road network.
Schreckenberg’s team has spent plenty of time analysing driving patterns and the behaviour of motorists and has so far identified several groups.
Some 44 per cent of motorists immediately react to traffic jam reports on the radio, changing their route and then often causing a traffic jam elsewhere. Another 42 per cent of motorists described as “conservatives” simply continue driving on the same route and hope that the congestion will soon end.
Surprisingly the research has uncovered a smaller sub-group of 1.5 per cent among the “conservatives” who always travel the exact same route and spend less time in traffic jams than all the other motorists.
Changing lanes during a traffic jam also has little to no effect, the research has found. Apart from such obvious obstacles as accidents or road construction, lengthy traffic jams are often simply caused by one motorist braking suddenly, setting off a chain reaction of all the cars following closely behind.
All the data collected by the team is based on hard facts. A simulation model uses data from 2,500 automatic traffic data detection units positioned on the motorways in the state. Updated every minute, the data includes vehicle speed and traffic flow.
Solutions offered by car manufacturers will in addition complement advanced traffic control systems.
The premium car makers say the technology could be implemented speedily but that government directives and legal loopholes have to be closed.

· Reino Gevers