ABSTRACT
Snow and ice control techniques in North America, and especially in the USA, have tended to focus not on preventing bond formation between ice and the road by pre-salting, but on bond destruction. Efficient clearance of highways, snow-fighting programmes, and even ploughing competitions have been the pre-occupation of municipalities, counties and states. There are probably two major reasons for this difference in emphasis as compared with that in Europe:
early experiments with ice-detection sensors were disappointing, with unreliable equipment and whole systems that did not work satisfactorily;
there was a lack of communication between highway engineers and meteorologists (Thornes 1986).
In addition, in many parts of the mid-West and the North-East, in what is often called the 'snow belt', large cities and conurbations have annual expectations of snow exceeding one metre, and in bad winters blizzard conditions can easily dump two or three times this amount on these settlements. For example in Wisconsin an average winter season has 30 winter storms which leave about 130 cm of snow.
