The aim of this project is to estimate the distribution of different road surface conditions on the basis of the 1993/94 to 1996/97 winter road surface condition follow-ups. The distribution of road surface conditions in terms of time and vehicle mileage was estimated for four climate zones: southern, central, northern Sweden (lower) and northern Sweden (upper) and for six categories according to the level of winter maintenance, A1-4 and B1-2. The time periods were November 15 - March 15 in southern Sweden, October 15-April 15 in central Sweden and October 1-April 30 in the rest of Sweden. Road surface conditions were divided into seven groups: snow-free dry ground, snow-free moist/wet ground, packed snow/thick ice, thin ice/hoar frost, loose snow/slush, bare wheel-tracks and elsewhere snow/ice, thin ice in wheel-tracks and other ice/snow elsewhere. One of the objectives of the project was to have a description of the qualities of the winters to accompany the summary and analysis of the distribution of road surface conditions. To describe a winter in weather terms information is used concerning the temperature, precipitation and the number of 24 hour periods with snowfall amounting to more than 2 mm snow in melted form. (Author/publisher)
Samenvatting