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Black ice, sometimes called clear ice, refers to a thin coating of glazed ice on a surface. The ice itself is not black, but virtually transparent, allowing the often black road below to be seen through it. The typically low levels of noticeable ice pellets, snow, or sleet surrounding black ice means that areas of the ice are often practically invisible to drivers or persons stepping on it. There is, thus, a risk of skidding and subsequent accident due to the loss of traction. A similar problem is encountered with diesel fuel spills on roads. == Definitions == The term ''black ice'' in the United States is generally used to describe any type of ice that forms on roadways, even when standing water on roads turns to ice as the temperature falls below freezing. Three other definitions of black ice by the World Meteorological Organization are: *A thin ice layer on a fresh or salt water body which appears dark in colour because of its transparency; *A mariner's term for a dreaded form of icing sometimes sufficiently heavy to capsize a small ship; *Another term for ice on rocks in the mountains known equally as ''verglas'' (glaze ice). 抄文引用元・出典: フリー百科事典『 ウィキペディア（Wikipedia）』 ■ウィキペディアで「Black ice」の詳細全文を読む スポンサード リンク
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