What is black ice?
Black ice is a deposit of ice which forms in a way which causes it to be transparent. Because the ice is totally clear, it is often invisible, which makes it very dangerous. Motorists are often at risk from black ice because they don’t see it on the roads, but they can still skid on it. Pedestrians and cyclists aren’t immune to the dangers of black ice, as anyone who has fallen on seemingly safe pavement in the winter can tell you. The formation of black ice begins when rain, fog, or mist deposits ice on pavement in cold weather. The latent heat of the pavement slows the freezing rate, so these droplets of water run together before they freeze. As a result, the air bubbles in the water are forced out, and the frozen sheet of ice which forms is almost completely clear. Black ice often blends in with deposits of rain on a road, and it can also form with a matte appearance which makes the road surface look clear and dry. Due to tricks of the wind and winter weather, black ice can form whe
night. From semi tractors to SUV’s to vans, whatever cars were there at the time, they were just bouncing off each other like bumper cars,” said Deputy Police Chief Mike Ryan. About 15 people were taken to the hospital, none life threatening injuries, police said. It seemed no one-not even emergency responders-could keep from slipping and sliding on the ice rink that was Halsted Street. A couple of medical workers fell as they tried to reach victims, and police had to work to keep their balance. Black ice is a term used to describe the frozen stuff on a blacktop road. That makes the ice all but invisible to motorists, who are only able to see the dark-colored pavement. There are a lot of variables in black ice formation: It is usually deposited by freezing rain, mist or fog. Because it contains relatively little entrained air in the form of bubbles, black ice is transparent and thus very difficult to see ( as compared to snow, frozen slush, rime ice, or other typical roadway forms of i
