青海省处于寒地区,大陆性气候的特征很显著。由于气溫的日較差很大,因此,在冬季无盖面冰层的河流河底,往往結有大量河底冰,如南門峽等站河底冰层有时厚达20厘米多。河底冰多在夜間形成,到白天,随气溫的升高在中午前后即浮出水面,随流 Qinghai Province is in the cold area, the characteristics of the continental climate is significant. Due to the great temperature day, a large number of river bottom ice often occurs during the river bottom with no ice covered in winter. For example, the river bottom ice of the Nanmenxia Gorge is sometimes as thick as 20 cm. River ice at night to form more, to daytime, with the rise in temperature before and after noon surfaced, with the flow