Often ice is associated with being a white color or a clear color. Where does the term black ice come from? The term black ice refers to a thin layer of difficult to see ice that accumulates on the roadway. Since the roadway is much darker in color than snow and it is difficult to see the ice, the term black ice caught on. Black ice can form in a variety of ways. One ingredient that is needed is a road surface that is below freezing. The moisture that makes up the black ice can form on the road from freezing of preexisting water, dew that becomes frozen, freezing drizzle, freezing rain or snow that melts then freezes on the road. The ice can be hidden by a thin layer on water on top of the ice. One characteristic of black ice is that it is very difficult to see. It is thin and clear. There can be water on top of the ice that also makes the ice difficult to see. The slipperiness of water and ice can make it easy for a vehicle to slide and lose control. Since the black ice is difficult to see, motorists will be driving too fast for the road conditions and this makes losing control of the vehicle even more dangerous. It only takes very light precipitation to produce black ice. It can also occur when no precipitation occurs such as when pre-existing water freezes or dew freezes on the road. Any time it is below freezing with the potential of ice on the roads, motorists should use caution. Black ice is most likely to develop first on bridges and overpasses. |