Cities could ease congestion and improve safety during snowstorms by tweaking the timing of traffic lights to take road conditions into account.
Researchers at the University of Waterloo collected data and ran computer simulations to determine that adjusting the signals at intersections in bad weather could reduce delays by up to 20 per cent.
"We need to have weather-responsive signal plans," said Liping Fu, a civil and environmental engineering professor at Waterloo.
Signals in modern cities are timed using optimization models that analyze factors including traffic volume and speed to safely get as many vehicles as possible through intersections.
"The problem is that those parameters all assume normal weather conditions," said Fu, director of the Innovative Transportation System Solutions (iTSS) Lab.
"In the winter, if the road surface is covered with snow and ice and visibility is poor, the numbers are not the same."