地球表面异常寒冷的地区积雪常年不化,时间久了,就形成了蓝色透明的冰层,冰层在压力和重力作用下,沿斜坡缓缓移动,逐渐形成冰川。冰川以结晶的冰川冰为主体,还包含一定数量的空气、液态物质和岩屑。冰川主要分布在南极和北极地区,中低纬度的高山也有冰川存在。地球上的冰川大约有2900多万km2,占陆地面积的11％,全球淡水资源的4/5积聚在冰川中。 In the area with unusually cold snow on earth, perennial snow does not form. Over time, a blue and transparent ice layer is formed. Under the action of pressure and gravity, the ice layer slowly moves along the slope and gradually forms a glacier. The glacier is dominated by crystalline glacier ice and contains a certain amount of air, liquid matter and cuttings. Glaciers are mainly distributed in the Antarctic and Arctic regions, glaciers also exist in the mountains at the middle and low latitudes. About 29 million km2 of glaciers are on Earth, accounting for 11% of the land area and 4/5 of the world’s freshwater resources accumulate in glaciers.