It causes the ice to advance and retreat every year. 使得冰盖面积每年都在扩大和缩小
Both poles of our planet are covered with ice. 地球的两极都被冰覆盖着
when the little there is is locked up as ice. 那里仅有的一点水也结成了冰
Since the last Ice Age they've become cut off from the outside world. 自从上一个冰川期以来 它们便已和外界隔绝
For five months of the year it's sealed by an ice sheet over a metre thick. 每年中总有5个月 湖面被1米厚的冰层覆盖
This vast barrier of rock and ice is so colossal it shapes the world's climate. 这条岩石与冰川组成的巨幅屏障极其宽广 甚至能改变全球气候
the ice itself is constantly moving, 冰川也在不断移动
A moulin - a shaft in the ice opened by melt water as it plunges into the depths of the glacier. 冰川瓯穴——由冰融水凿成的 直达冰川深处的圆筒状竖井
All mountains everywhere are being worn down by frost, snow and ice. 世界各地的高山都在不断经受 森林、积雪和冰川的消蚀