These snow-covered forests encircle the arctic, from scandinavia, through Russia, to Alaska and the rest of North America.
这些白雪覆盖的森林环绕着北极，从斯堪地纳维亚半岛，穿过俄罗斯，再到阿拉斯加以及北美洲其他地方。
But close to the north pole, the winters are too long and too cold for even the hardiest of trees.
但在靠近北极的部分，冬季太长也太冷，即使再耐寒的树也难敌。
This is the tundra, and it stretches all the way to the shores of the arctic ocean.
这就是冻原，它一路延伸至北极洋的岸边。
Here, conditions are even more extreme than in the forests.
这里的环境甚至比森林之中更加极端。
During the two months of winter darkness, temperatures may fall to minus 50 degrees celsius.
在冬季黑暗期的两个月之间，气温可能会降至负五十摄氏度。
The ground deep beneath the snow has been frozen solid since the last ice age.
深埋在积雪之下的地面，自从上次冰河期就已完全冻结至今。

There is no shelter of any kind. Very few animals can survive here.
这里全无任何遮蔽。少有动物能在此生存。
But this is one which does. An arctic fox.
但这一种可以。北极狐。
It has the warmest fur of any mammal.
它有着所有哺乳动物中最保暖的毛皮。
And it can survive blizzards that may rage for days on end.
还能在一连多日的暴雪肆虐下存活。
It must nonetheless eventually eat something.
尽管如此，它们终究需要进食。
But how is that something to be found when you're all by yourself in this desolation?
可是当你独处在这荒凉境地，还能找到些什么呢？